HOW TO: A4 Intake manifold cleaning

Is this generally more of an issue with ALH vs BEW? Since ULSD was standard since 2006/07 - I am sure there is bound to still be a decent amount of build up in my 2004.

I recently got the Dynamic EGR upgrade along with my tune and am interested in cleaning EGR/Intake when I perform the next timing belt. I figured if I start clean - using only ULSD grade diesel - it should remain clean for years to come.

Is it suggested to check out the condition of the EGR first and go from there? If the EGR is only slightly gunked up - is it advised to JUST clean that and leave the intake in place - or is it inevitably going to be a mess? I like the idea of having a "like-new" air system and would rather do the job once and do it right. Just wondering from other PD/BEW owners experience.

I am not feeling the power upgrades I should from a Stage 1.5 tune and my fuel economy isn't great at the moment. I also plan on cleaning the MAF.

Thanks for the instructions. Completed the job on my wife's car. Looking forward to an improvement in MPG and power.

Twin_Guns18 said:

Thanks for the instructions. Completed the job on my wife's car. Looking forward to an improvement in MPG and power.

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How much gunk did you scrape out?

Great and helpfull write-up.
I just wanted to second or third the potential mess created by this project. In hindsight, I would have gladly spent an hour creating shields an coverings for anywhere the soot might get. I spent ~ 2 hours cleaning floors, clothes an shoe soles after the project was "done".
Also, I would recomend (what I did not do) to build in time to clean the intake ports, for the newb I suspect that would be an extra 2 hours if not more. Due to my poor planning I will, at a later date (when the temperature is nicer), have to repeat most of this exercise. Live and learn, or don't and repeat.

I'd also like to note that the car seems to be starting a LOT easier with much more consistency(heater being on or off). It appears that my intake was actually not letting in enough air to let the motor start quick. It now fires up after half a crank. It's almost instant. What a difference!

+1 on notagearhead's comment about this being a messy job. Mine spent a night in a tub of parts cleaner solvent, then a trip to the local DIY car wash for a rinse, then back to the parts cleaner tub for another few hours followed by a short scrub, then back to the car wash for the final rinse.

That was 1.5 months ago. Have not noticed any difference in fuel economy or power.

The document was updated with the following:
"Original instructions were created by GeWilli with Snowball’s assistance. It is outdated as we have determined better methods. I want to thank those guys to help get it started and I want to thank the TDIClub forums for finding improvements on doing this job, particularly JasonTDI"

Does anyone know if the better method for cleaning the Intake Manifold has been documented

Egr delete kit

Does the egr delete kit help with carbon build up?

Bri said:

Does the egr delete kit help with carbon build up?

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It eliminates carbon buildup. What clogs the intake manifold is a combination of oil (which is always present in the post-turbo intake tract) and soot from the exhaust gases. No EGR = no soot in the intake = no clogging.

RacerTodd said:

What clogs the intake manifold is a combination of oil (which is always present in the post-turbo intake tract) and soot from the exhaust gases.

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This might work https://www.youtube.com/watch?v=AT2w-ejVE14
Going to get one

Lesson's Learned

Tackled this job over the course of a few nights and followed DeafBug's How-To for the most part. Thought I would pass on a few lessons learned.

Things I wish I would have known/done differently:

-I wish my spare manifold was completely clean prior to attempting this job. Cleaning out the last 30% was a SIGNIFICANT pain, and I was simply ready to put stuff back together so I could begin the other clean-up job: my garage floor now speckled with oily-carbon chunks.

-I went ahead and chemically cleaned the exhaust side of the turbo since I was kind of in the area and already filthy. When removing the nuts from the exhaust flange, it pulled the studs out of the turbo instead of just removing the nuts. I wish I had replacement studs and nuts prior to doing this job.

-I removed the flex pipe from the exhaust manifold in order to have more room back there. I wish I had proper nuts to put back on these also. I scrounged around and found something to work...hope they hold appropriately. I ordered the IDparts intake manifold cleaning kit for $22 and I should have gotten the Turbo Install Kit for $29 that included other gaskets and nuts. I discovered this after the fact...

-My Christmas list now includes a pair of cable hose clamp pliers. When midnight rolls around and I'm tired and filthy and angry and engine crud is dropping into my eyes, I really don't want to be trying to convince a hose clamp to come off or go on with a pair of channel locks. Ugh. Never again.

-I tried a citrus-based wood stripper at one point to clean the intake manifold and it caused some small pitting. Shouldn't have done that. Simple Green did work well, though, and would have worked better had I soaked it longer (a few weeks probably). Other people have said that Simple Green will cause pitting, but the label says it's safe on aluminum.

-I had one Guinness Draught to last the entire project. What was I thinking?!

Things I did right:

-Cleaning the intake ports while I was there. Now, I don't have to worry about a lip of crud breaking off and getting sucked in.

-Draining the intercooler.

-Buying a set of long ball-end allen wrenches and short stubby 3/8 drive 5mm and 6mm allen wrenches.

-Removing the flex pipe to free up some space back there.

-Giving myself several days to get this done and getting to know my wife's 03 wagon "Stasia" a little better.

mathanz said:

Simple Green did work well, though, and would have worked better had I soaked it longer (a few weeks probably). Other people have said that Simple Green will cause pitting, but the label says it's safe on aluminum.

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Just to add to this, the regular simple green is indeed mildly corrosive to aluminum.. albeit not that much. However they do make two products specifically meant for aluminum:

Simple Green Pro HD Heavy Duty Cleaner
Simple Green Extreme Aircraft and Precision Cleaner

I've heard from some friends in the military they use the aircraft one alot. I haven't tried it on intake parts though.

I am cleaning mine as we speak. 97 Passat 1Z TDI. Fixed EGR, no takey off. Mine was as bad as any I've seen posted here, maybe worst. How the engine still ran defies logic. I used the fire breathing dragon/flame thrower method, cable in a drill, long screw driver, other scrape objects and purple degreaser. Now on to the intake ports when I get time. That black stuff really puts up a nice cloud of smoke. Fun, fun.

How did you protect the EGR valve during the burning?

Unfortunately with the design of the A3/B4 manifold and EGR being together, it's not recommended you use the fire trick...starting with the A4 that's the only way I do it! Back with those ones, I had to scrape and soak and take to the pressure washer. It's not worth the risk of damaging the EGR seal components.

I followed Abacus's advice and wrapped a cold wet rag around EGR, blow/torched it, then used purple de-greaser, kept the EGR up so no fluid went into it. I also cleaned the Cam rails. Thanks to Steve Addy & Abacus for good instructions. Car never had very good power, since I owned it, now I know why. Unbelievable the differants.

With all that heat on the EGR valve shaft, I don't see how a wet rag around the outside of the valve could keep the seal cool but glad it worked for you.

Col Sanders:

1. Great chicken!

2. Did you do the cleaning on the 2001 in your signature? What were the symptoms that led you to the cleaning?

no start after cleaning

Apparently, I'm the dunce of this thread, because after reassembly, I can't get it to start.

I double-checked the vacuum hoses and made sure they were hooked up correctly (checked against this diagram: http://i75.photobucket.com/albums/i306/BlackWagon/turbo_tdi_N75_N18_N239m_EGR_VNT_Act.jpg). I think I hooked up the electrics properly too--the electric junction to the N18 vacuum junction and the electric hookup in the turbo supply hard tube. I swapped 'em the other way just in case, but still no joy.

Any ideas on the cause, or what to try next?

Is the ASV staying open while cranking?

What did you disconnect or remove and what else did you do other than cleaning the manifold?

ASV is most likely after this work. Due to vacuum hook up issues.

KLXD and Dan:
I figured as much. I looked at four or five vacuum diagrams online to make sure I hooked it up right. (https://uploads.tapatalk-cdn.com/20160113/9c9dbcc14a783ad244db6a54e21564d7.jpg) I double checked last night, and I think I got everything right.

My wife watched the ASV while I cranked the engine, and she said it never moved. So I don't think it's closing on me and causing the no-start.

If the ASV is the problem, how can I test it? My theory: disconnect the vacuum hose from the ASV, plug the line with a a golf tee, and then the car should start. Correct?

correct.

You should also be able to look down the intake pipe, and ensure the butterfly is open and stays open.

Since the engine will run with the intake manifold and exhaust removed, if it is not an air blockage it is hard to see how this job can be the cause.

I think that hooking the crankcase vent heater plug to the ASV has also been done...

If the ASV is indeed open, then I would think that perhaps you blew the fuse to the fuel shutoff solenoid on the fuel pump as being the next most likely cause.

I had a beer and worked on a different project for a bit. I came back to the VW and after a long crank, finally started. Maybe I was just being overly worried about burning out the starter before, and didn't wait long enough to catch. In any case, since then, I've started it without incident several times, and now it starts right up, better than it did before the cleaning.

But nothing ends so simply, and now I've got a code. I'll get back to y'all with the VAG-COM results.

The car has *way* more power than before once the engine is warm, but the starts are still rough. I got a glow plug code, so I'll be changing those out soon. Any tips or tricks before I start the job?

Yes, test to make sure it's actually caused by the plugs and not the harness and discuss it in a glow plug thread if necessary.

Pulled the intake off my 96 Passat sedan due to loss of power. It wasn't very bad. Now what.
Also pulled the intake off my 96 Passat wagon that runs great, it was much dirtier.

Going to switch from one to the other since I'm going to sell the sedan and the wagon is leaking a little from the EGR weep hole.

The turbo often has a slight oil mist on the compression side; the crankcase ventilation feeds into it. Then the EGR adds fine diesel soot. Heck of a mess, layer after layer.

The 2005 models had less of an issue. I have never had to clean my intake, and the ones I have seen were not too bad.

Bringing this one back up... started working on this, but... someone had been there first, and the bolts holding the flex pipe from the Turbo to the EGR cooler have been massacred internally (Allen-head bolts)... I'm afraid that if I try Bolt-Outs, they'll just break off the bolt heads... Should I bother trying to get this done? The front part of the intake was quite clogged and I suspect that down near the ports it may be worse...


Y.