04 BEW PD stalling at idle

[pruzink]

My 2004 BEW PD Jetta has developed an intermittent stalling at idle problem. This doesn't happen very often (maybe 1 out of every 50 times that I am stopped with the car in drive at a light or traffic). No codes are being set. I have a 2 micron Cat fuel filter which I change once per year. After the car stalls it starts right back up and runs fine. The car has 146,000 miles & I do plan on pulling the valve cover soon to inspect the cam & lifters; but I do send oil samples out for analysis and so far the wear metals look good & the last time that I looked at the camshaft (about 20K miles ago) it looked good.
I did a search on here & posts that I saw as potential culprits were the crank sensor, the in tank fuel pump, camshaft wear. I will be paying attention to see if this only happens when the air conditioning is on. When it does happen, the car RPM at idle are steady & it just dies with no reason.

 

[2004STARWARSTDI]

stalling

Also look into relay 109

 

[BobnOH]

you might try bumping the idle up just a bit, I think it's Block 002

 

[pruzink]

A couple of days ago I filled up & didn't have any stalls for 160 miles so I thought that maybe it was the in tank lift pump. Several years ago I was reading a lot of threads about lift pump failures so I bought a spare to have on hand (I also did the mod so the tandem pump can pull through the lift pump if it dies). In any case, I installed the new lift pump today (I do love VW's design for pulling the pump out of the top of the tank; it sure beats having to completely drain the tank in order to remove it from the bottom. It only took about 10 minutes to replace the pump). Unfortunately, on my way into work tonight I had 2 more stalls at idle. I am thinking that it might be more related to heat (today it was warmer than the other days when I didn't have any stalls). I have Vagcom, so tomorrow I will scan for codes (I read a post where someone had an implausible crank speed message; I know that some messages don't set the "check engine" light). I will also try bumping up the idle RPM a tad.

 

[lbirunner]

This happened to me a couple of days ago. And it also happened a few times last summer.
I have new lift pump, new Colt Stage 1 cam and timing belt since those events last summer.
I'm suspecting Injector wiring harness connections but just starting to look into it.

 

[pruzink]

I did some more reading in here to see if I could come up with something that made more sense. I did find a post for something that might occur at this point. The ASV (anti shutter valve, this device is also called the intake flap) on these cars stays wide open for most of the time except on shutting down the engine; however, if the Exhaust Gas Recirculation valve goes 100% open & the mass air flow sensor is above the target value, the ECU will start closing in on this intake flap in order to get more Exhaust Gas Recirculation flow. When my engine stalls at idle, it is as if the ASV is going completely closed shutting off all air to the engine. Yesterday, I hooked up Vagcom to see if I could see it doing this; however, because my problem is only a very intermittent problem, everything worked exactly as it should for the 30 minutes or so that I watched it and all of the parameters were normal. At idle, my exhaust gas recirc flow stayed very close to the desired 220 mg/str with the EGR valve at between 70 & 75% open. Vagcom allows you to test the EGR valve (will open & close it about 3 times) and my EGR flow went to 160 mg/str with the valve open and 400 mg/str with the EGR closed. I guess that anything that would cause the EGR valve to go wide open or the MAF sensor to read greater than desired air flow at idle where I have my problem with the car stalling. My 04 BEW PD Jetta has a Pierburg intake flap and I found a write-up from Pierburg about throttling this valve on a Diesel to provide more EGR. If the EGR valve started getting plugged and started going 100% open at idle this could potentially cause the ASV to cut too much air & cause a stall; or if the MAF sensor was reporting more air than actual it could create this same problem. So far, I have not seen this happen, so I know that I am missing something else that is happening.

A couple of things that I need to look into more are: 1) Vagcom shows values for desired EGR Flow & Actual EGR Flow. Do these cars have a dedicated device for measuring this flow or is it calculated by some other inferred device? I did see on the Pierburg website that they also make a device for measuring actual EGR Flow. It seemed like the EGR Flow was often very close to the MAF value. 2) Is there any place that lists typical Vagcom Engine parameters at idle & cruising speed? For instance, what would the highest deviation that I would want to see between the 4 injectors for fuel supplied to the engine. Or what should my MAF sensor read at idle or 65MPH.

I saw a few posts about the intake flapper (ASV) going bad. On the BEW PD engine this is a DC stepper motor driven valve. There are plastic gears that can get stripped if the flapper gets gummed up. This part goes for about $450 so I don’t want to change it unless I am certain that it is causing my problem. I think the next thing that I will do is pull & clean the EGR just because I know that they typically get dirty; the reading that I saw with Vagcom don’t really lead me to think this will correct my problem though.

 

[PDJetta]

"When my engine stalls at idle, it is as if the ASV is going completely closed shutting off all air to the engine. Yesterday, I hooked up Vagcom to see if I could see it doing this; however, because my problem is only a very intermittent problem, everything worked exactly as it should for the 30 minutes or so that I watched it and all of the parameters were normal."

If you unplug the throttle housing electrical connector, it won't hurt a thing (except for a CEL and code, which you can clear) and the default position of the throttle plate is full open and it will not close, since a spring holds it open and the housing electric motor is not getting power, if the plastic gears are not stripped. Since this is an intermittent fault, drive around with the throttle housing unplugged for a few days.

If the car runs as it should after unplugging the throttle housing electrical connector, you have narrowed the cause considerably.

If the gears are stripped out in the throttle housing, you can feel it by manually opening and closing the throttle plate by reaching into the intake opening (the plastic pipe/boot must be disconnected to do this) with your fingers and pushing on the throttle plate (engine off, of course).

--Nate

 

[lbirunner]

That's a lot of good info to work with.
I'll check the condition of plastic gears and throttle plate. I'm assuming the ASV and throttle plate and flapper are all the same part.

I'm wondering what the ASV or throttle plate does when the EGR is disconnected? Would it be controlled to close more to cause more exhaust recirculation?

pruzink, just wanted you to know, I also have a cleaned EGR valve as of this winter. And I had another stall sitting at a red light with the A/C on and about 90 F outside temp.
I definitely think it is promoted by high temp.

 

[PDJetta]

"I'm assuming the ASV and throttle plate and flapper are all the same part."

Yes. The gears in mine stripped out, but it exhibited this by a grinding sound when driving and after the engine was shut off as the flap was trying to close. I got the replacement at 1stvwparts.com for about $350. My local dealer wanted about $550!

Here is my old one with its cover pried off:







"I'm wondering what the ASV or throttle plate does when the EGR is disconnected? Would it be controlled to close more to cause more exhaust recirculation?"

The throttle will still be active if the EGR is blocked and can cause a little mileage hit, since it closes off, but the exhaust flow is not present to relieve the vacuum. You can remove the throttle plate/disc from its housing if you like. Two torx screws hold it to its shaft. But if you do this, you loose the air cut-off when you turn off the key. This could be important if you experience an oil-fueled engine run-away from a failed turbocharger.

--Nate

 

[lbirunner]

I think the next thing that I will do is pull & clean the EGR just because I know that they typically get dirty; the reading that I saw with Vagcom don’t really lead me to think this will correct my problem though.

pruzink, Have you found anything new?

I did a lot of reading on the engine speed sensor and from what I've read I don't think that's causing the problem. Although if I can't find any other clues I might use a heat gun on the sensor to see if I can cause an event.

I'm having almost daily occurrences (stalls) now, I think it has to do with outside air temp because we are well into the 90s here in the afternoon. But engine was just barely up to normal temp, I had only driven 5 miles at this point. It stalled just before merging onto a highway, I was at idle rpms and just about to hit the gas.

PDJetta, thanks for the pics, I'm going to check the gears in my ASV today.

 

[pruzink]

Hello lbirunner, it didn't stall on me for about a week, but it did stall on me on my way home from work today. I still can't think of anything to correlate a rationale as to when it doesn't stall versus when it does. When I was watching the EGR Valve Position, EGR flow, Mass Air Flow I was thinking that it might be related to the rate at which the two devices (EGR Valve & Intake Flapper ASC valve) change. For instance, driving on the highway the EGR valve is only open about 20%; then if you are getting off on a very short exit ramp the EGR valve needs to end up opening to about 75%. If the valve overshoots & goes completely open, the ECU might request the intake flapper to throttle to force more EGR flow. When I was watching the interaction between these things I did notice some times during quick engine RPM changes when the EGR did go wide open. Even though I suspect that it is the Intake flap ASV valve, right now because it isn't doing it often I don't want to unplug it. The thing that I find puzzling is the randomness of it; it doesn't do it often & there is no reason. I need to pull the valve cover & get a look at the camshaft; because I have a BEW with 147K miles anything abnormal I am concerned about cam wear being related.

 

[lbirunner]

I need to pull the valve cover & get a look at the camshaft; because I have a BEW with 147K miles anything abnormal I am concerned about cam wear being related.

Hopefully you won't find a problem there. But this is about the same mileage where I found my cam to be worn. Lobes were flat (chamfer was gone). I replaced it with a Colt stage 1. I'm very happy with it.

Back to the stall problem...
Here's something I found from Frank06 pertaining to an idle problem. (Post #40, In this thread.)

Here is a novel approach. This happens to almost every PD I've looked at.
The EGR sticks open. It pumps noxious gas back into the engine and causes a slight stutter when it returns to idle.
More than that, when you accelerate, there is a sudden leap as the turbo kicks in.
What happens on acceleration is there is a reversal of flow of exhaust gasses coming through the EGR that is stuck open. When the turbo finally overcomes that exhaust pressure, POP! The engine suddenly stops getting recirculated gas and get a nice load of fresh, clean air and the thing takes off.
I've got a pictorial I have to do to show what happens to the EGR, but basically, the steel rod that operates the EGR seal is stuck open due to: 1) carbon on the operating shaft, 2) a cocked bearing on the servo shaft arm and 3) a sticking servo motor.
Let's put it this way... the EGR servo is a lousy piece of JUNK!
Easiest thing to do is get the damper plate to close completely and pull the EGR electrical plug. Get a tune to delete the EGR CEL.

I found it interesting because I think I've noticed this behavior of sudden bursts of power when taking off from a stop.

I'm starting to think about doing the EGR delete and getting a tune to take care of the CEL and have the ASV only operate (close) in case of turbo failure.

But before I do anything, I still need to check the condition of the gears on the ASV.

 

[lbirunner]

Disconnected (un-plugged) ASV (throttle plate)

I took Nate's advice and disconnected the ASV (throttle plate) last night. Test drive was driving to work this morning (25 miles).

I wasn't expecting to notice anything real different except maybe not stalling later today on the way home (so I didn't hook up the VAG-COM). But what I found was my temp gauge was reading below normal after getting off the highway (after 25 minutes of driving).

Then sitting at the traffic light (for what seemed like a very long time) the temp rose to the normal midpoint. At the green light I stepped on it pretty good up to 65 mph. And noticed the temp dropped 1 notch immediately.

I know the temp gauge is very coarse so I'm expecting when I get the VAG-COM on it I'll see that it's not even getting up to normal operating temp (185F ?).

Is this temperature differential normal with the ASV disconnected?

 

[LNXGUY]

You shouldn't see any temp drop if the ASV is disconnected. Any chance you've got a bad CTS?

 

[PDJetta]

Right. I suspect a bad temp sensor. The original ones drop like flies. I had to replace mine due to guage fluctuation. The new temp sensor fixed the temp flucuation (really no temp fluction, just the guage was fluctuating slowly due to a failed temp. sender).

--Nate

 

[lbirunner]

With the ASV disconnected, I notice (via VAG-COM) the EGR is no longer being cycled, the duty cycle remains at 100% all the time (I assume this is fully open).
Is this to be expected?

So, if I no longer get "stalls" it will be related to either the ASV or the EGR operation. Because, as I understand it, the ASV opens/closes depending on EGR (please correct me if I'm wrong here.)
I'm driving with VAC-COM connected all the time now. There was plenty of heat here yesterday and with the A/C on I didn't have any stall issues on my drive home.

BTW, it sure does run better with the EGR and flapper disabled. I get more consistent power through all gears.

Also, changed the temp sensor but coolant temp is still drifting. I let it drift above 90 C while sitting in the parking lot at work and then drove around and watched it fall to 70 C.
I'll change the thermostat tonight.

 

[lbirunner]

Update:
Driving home on Friday with A/C on and high outdoor temps above 90F, I stalled 2x while sitting at a traffic light (in neutral). Started up (as usual) with no problem.
This is with the ASV disconnected. I wish I had the VAG-COM connected, but no, I didn't.

Any suggestions for next step to troubleshoot this?

Here's a recap of what's been done:
Cam and lifters replaced last fall.
MAF cleaned.
Applied some silicone grease to MAF, EGR, Main Injector connectors (this solved random studder/miss problem while at cruising speeds).

In general the engine is running great, just have random stalls at idle when outside temp is high, > 90 F.

I'm open for suggestions...

 

[pruzink]

I pulled my EGR & cleaned it today. It was dirty, but not that dirty where it wouldn't have opened & closed as needed. I still had the problem with a couple of random stalls after I put a nice clean EGR valve back in. Do you have the 09A automatic tiptronic transmission lbirunner ( I wonder if it could have something to do with the overdrive engaging)? It sounds like your problem is exactly the same as mine. I thought that mine might be related to the Air Conditioning being on, but it does it with or without the AC on. Mine is due for a transmission fluid change. I don't like that VW doesn't have a dipstick to check to check the fluid level. I had a car once where a solenoid valve failed in the tranmission so that overdrive never disengaged which would stall the car every time that it stopped. The weird thing with this is that it is so random. I have gone 3 or 4 days without a stall, and then I'll get a couple out of the blue; I just can't correlate anything to when it happens.

 

[pruzink]

I just looked at your profile & I see that you do have the 09A transmission and that you have replaced the solenoids on it. How long ago did you replace the solenoids. I have a VW manual on this transmission, I will have to take a closer look at it. My understanding of "overdrive" is that once you get up to cruising speed a clutch will engage & lock-up the torque converter to eliminate the in-efficiency of a hydraulic coupling when you don't need it. Could this somehow just be grabbing at idle enough to stall the engine?

 

[lbirunner]

I replaced the solenoids about 1 1/2 yrs ago (30k miles).
I don't know about the transmission having anything to do with this problem. And many of my stalls are while in neutral. Maybe this doesn't mean anything, but I don't feel anything from the trans when the stall happens. But hey, I'm with you, I have no idea what this could be. BTW, I also replaced the fluid last month.
And although there is no dip stick, there is a level check, so to speak. It's an overfill screw that you can open up after refilling the trans (at the correct temp range) to release the excess oil. When the oil stops flowing out of this "orifice" you should have the correct oil level.

Have you done anything with the speed sensor? I will probably look at this next, I'll check the wiring and maybe just replace it to see what happens.

Also, there is at least one common denominator, outside temps.
I had this stalling problem last summer but didn't have it during the winter months.
I've also had it stall when the engine was just barely warm, not completely up to temp and the outside temp was over 90F.

 

[pruzink]

I agree with outside temperature affecting this problem. I doubt that it is as hot here in Connecticut as it is in Texas; but today it was cloudy & cooler here and my car was fine all day. I used google to see if there were other forums like VW Vortex where someone might have had this same problem & I did find one where someone was having this issue and they took it to a dealer for diagnosis & repair. The dealer said that their tandem pump was intermittently stopping fuel to the engine & after they replaced it the problem was fixed. A new tandem pump goes for about $350 so I don't want to replace it unless I am reasonably certain there is a problem with it. I did a search in here for people that have had problems with tandem pumps. There was a recall for certain VIN# BEW engines but the problem with the recall was more of an issue with a gasket not sealing & fuel leaking as opposed to an intermittent pumping problem. There was a post by "PDJetta" that he had dismantled his tandem pump and I sent him a private message to ask what kind of internals it had. I would think that it is a positive dispacement pump but with it being driven by the camshaft I just can't picture it cutting out intermittently. There was a couple of posts from people that were looking at tandem pump fuel pressure and it looked like at idle that it put out about 50 psig pressure and at normal driving speed it put out about 100 psig. I typically do the "diesel purge" procedure every year when I change my fuel filter and I know that the return oil from the PD injectors gets quite hot; I replaced my 3 way thermostatic valve at the fuel filter with a Kerma widget a couple of years ago because I felt that 95% of the time it was better to send that hot fuel back to the tank rather than back to the injectors (the Kerma widget just blocks the return port at the fuel filter & routes the return fuel back to the tank). I have a 20 page PDF file with the recall info on the Tandem Pump that has pictures of the pump & I will take a look to see if I can connect a gauge to see what it is doing.

 

[PDJetta]

Pruznik, you've got mail (a PM).

--Nate

 

[pruzink]

lbirunner: this is the reply that I received from PDJetta regarding his inspection of a tandem pump internals

"I had the LUK tandem pump. The fuel pump side was a vane type pump. From memory, the pump shaft held two spring loaded paddles (basically rectangular pieces of steel, about 1/16 inch thick) and the paddles (or vanes) pressed up against the round (or oval) pump cavity. As the shaft rotated, the fuel was pushed from the intake to the output side. I have read on this list of a verified failure of the tandem pump (a LUK brand) where one of the two little springs broke, the springs that push the vanes against the pump housing (wall). I don't remember if this resulted in a total pump failure, or reduced pressure. If the spring no longer pushes the vane against the pump housing, fuel will leak past the vane as its rotating.

I would perform a pressure test of the pump, or at least a volume flow test. DanG has provided details on how to do this on one of his posts. Other than that, the only way to verify an internal failure is disassembly and IIRC this usually ruins the pump seal and you can't get spare parts. Unfortunately, I discarded the old pump long ago, so I don't have the springs. I think the fellow that had the failure actually made/found a spring and got it back together and it worked.

The Bosch replacement I bought (by luck it was a Bosch) is a gear pump, totally different design.

I also think Pierburg made tandem pumps for the BEW. What make is yours?"

I checked my tandem pump and it is a luck. I would agree that the Bosch gear design pump would be more reliable. With the vane type pump you are relying on springs to keep the plates sealed against the pump housing as the shaft rotates and the springs are a weak link. I will see if I can find the "DanG" writeup on testing this pump; he did an excellent writeup on the operation on the intake lift pump (which I just replaced after I started having this problem) and a modification to make to this pump so that the tandem pump could pull fuel from the tank without the lift pump operating if it ever failed (there were a couple of different lift pumps being used, one of the designs would allow flow through it if the pump didn't run, the other did not).

Thanks for the information on the Tandem pump PDJetta.

 

[pruzink]

This is the thread from DanG on testing the tandem pump: "http://forums.tdiclub.com/showthread.php?t=353273"

 

[pruzink]

http://forums.tdiclub.com/showthread.php?t=353273

A blue link that works without copy & paste

 

[PDJetta]

See Post # 3 in the link above. It makes reference to the broken vane spring.

--Nate

 

[lbirunner]

Stall event with log file. Can someone decipher this?

Ok, I finally have an update. Sorry it took so long.
BTW, I have a LUK tandem pump.

Two weekends ago I removed the EGR cooler and replaced my thermostat. And since then everything has been running great. And temperatures are approaching 100 F here (I think tomorrow will be a few degrees above 100, yea).

My point is I haven't had any stalls in this heat with the A/C running.

But sure enough, this morning on the way to work I had the VAG-COM hooked up and recorded an event at a stop light. Outside temp was 70 F. and the Coolant temp was not even warmed up yet (below 90C).

Here's a link to the log file.

Look around line 1017. I colored the lines in yellow. You will notice the Engine speed drops to zero. Then 10 seconds later it picks back up after I start the engine.

What I think is most interesting is the MAF reading pops up to 535 out of nowhere right before everything craps out (line 1017). And correct me if I'm wrong but shouldn't the MAF reading follow the fuel flow, i.e., increase fuel, then air flow increases?

Anyway, I'm hoping someone smarter than me can take a look at this data and have some suggestions. Please?

 

[pruzink]

Hi there. My car was fine for about 3 weeks also (zero stalls); but then out of the blue I started getting occasional stalls at idle (or almost at idle) again. I cleaned my EGR (it wasn't very dirty for 147K miles), but that didn't affect anything. The only thing that is really airflow on these cars is intake manifold vacuum. The anti-shudder valve closes when the engine shuts down, but then re-opens. There is no throttle body like on a gas engine to match air flow with fuel flow, it just sucks as much air as it can take. I don't know what #'s (air flow) the ECU is looking for before it tries to close in on the anti-shudder valve in order to get more EGR flow but that block of data at timestamp 500.84 (far left column) shows an increase in MAF from 350 to 535 mg/str (the 350 was typical for idle rpm air flow) so could this have caused the anti-shudder valve tochoke the engine in an attempt to increase EGR flow (the boost pressure also dropped a tad here but not much 1020mbar to 1010).
Another piece of data that is interesting is the injection quantity values just prior to the stall and just as the stall occurs (timestamp 500.84 is the stall). It appears that you coasted down a hill coming into this stop (or maybe were coming off of an exit ramp). From timestamp 483.67 to timestamp 493.77 pedal position sensor G79 is zero (foot is off pedal) as the engine RPMs coast down from 1974 to 1113 RPM with Injection Quantity & Injection durations all at zero during the coast down. I know that there isn't any device that actually measures the "Injection Quantity" (no actual fuel flow measurement device, so I guess that the ECU calculates that value based on what it is telling the Pump Deuse Fuel Injector to do (after you finish coasting to a stop & engine RPM drops below the 900 target it increases the injection quantity to about 4 mg/str. I wonder what affect a sticking vane in the tandem pump would have on these injection quantity values? Just prior to the stall, at time block 497.83, your engine RPM drops from 882 to 840 so the ECU to give some more fuel (injection quantity increases from 5 to 10). Everything seems to recover just fine, RPM return to normal at 900, airflow looks good and that is when it looks like you just stall.
What are your thoughts on the tandem pump (I have a Luk which is the sliding vane type, the Bosch is a rotary screw, I'm not sure about the Pierburg) being the culprit & killing the fuel to the injectors (the data point Injection Quantity wouldn't know that it wasn't getting fuel, it is just reporting how much it would normally have the injector supply if the tandem pump was working right).
At higher engine RPMs maybe the sliding vanes have enough centrifugal force to keep them working and prevent the tandem pump from starving the injectors of fuel? At idle if a spring is broken, maybe as the fuel gets hot a vane will stick and interupt the fuel.

 

[lbirunner]

that block of data at timestamp 500.84 (far left column) shows an increase in MAF from 350 to 535 mg/str (the 350 was typical for idle rpm air flow) so could this have caused the anti-shudder valve tochoke the engine in an attempt to increase EGR flow

I think the MAF spike is very interesting because air flow should not increase without an increase in fuel. If you look at the time stamp for the MAF spike you'll notice it actually occurs before any of the other numbers drop off. I wonder if the ECU is shutting down the fuel flow because of the "bogus" high MAF reading. Do I have a bad MAF sensor? There was no reason for the MAF reading to go high like that.

Also, remember, I had the stall problem with the ASV disconnected. So we can take that out of the equation.

I wonder what affect a sticking vane in the tandem pump would have on these injection quantity values?

I don't know about the pump. I guess it's possible that it could fail intermittently. But I would think it would be less random than it is. It smells like an electrical problem just because it's so intermittent.

BTW, the reason I had the VAG-COM connected the other morning is because the evening before, when the engine was cold, I started it up to go to the store and it stalled as soon as I put her in reverse. And after starting up right away, it did it a second time. After that, no more issues until the next morning. And I haven't had another stall since. Today was 104 F when I got off work and I drove home in stop and go (traffic lights) traffic with no issues.

I know one thing, if it's the pump (mechanical) it will eventually fail completely.

 

[pruzink]

If you think about what happens if you had a ball valve on the fuel supply that you quickly closed to the engines, those couple of seconds as the fuel stops flowing the engine stops working as a diesel and functions like a piston air compressor. I'm not sure if this would cause this momentary spike in MAF air flow, but I think it is possible.
The problem that we are both having is a very intermittent problem; the reason why I am thinking that it is not electrical is because it only occurs at idle or close to idle engine RPM. I can't think of anything electrical that would occur intermittently only then.
If you look at your data from time stamp 0.24 to 138.23 there is almost zero change in fuel injection quantity or MAF air flow. I am assuming the time stamp is seconds so this represents about 2 minutes of idleing. At timestamp 138.23 (still at idle) something like the AC cutting in drops the engine RPM from 903 to 861 so the ECU bumps the injection quantity from 6 to 10 & everything functions as it is supposed to. At time stamp 500.84 which is when you stall; the one thing missing in that data string is the fuel which is why I think the engine lost its fuel supply.
The Luk tandem pump looks like the pump toward the camshaft if the vacuum pump and the outer pump is the fuel pump. There is an outer cover on the fuel portion so I am thinking that if this cover is removed that the vane springs could be checked. The reason I am hesitant to do this is because I have read a # of posts where this cover leaked fuel & the pump needed to be replaced. The gasket for between the inside & the engine is sold but I don't see anyone selling this outer cover gasket.