IP Loses Prime on cold mornings

This is the 2nd time this has happened this year. It was 24 degrees this morning, and I couldn't get the car to start. I pop the hood, and there's no fuel in the line from the filter to the IP.

Last time this happened, I had it towed to the shop. They reprimed the pump, got the car running, and as soon as they shut it off they said the fuel immediately backed out of the line and into the filter. After replacing the filter and reprming again, all was well -- it held prime everytime. That was about 1000 miles ago.

What are the chances it's the filter again?? I assume that since it's only happening in the cold that something is contracting and opening up an airway in the fuel system.

Also, how do I reprime the pump myself without having to tow it to the shop again??

Easiest way is with a mityvac, just pull a vac on the return line from the ip until you get fuel in, or you can just pull it on the output from the filter and just back fill the filter.

I would check the drain on the bottom of the filter, if that's not it then start checking for leaks in the lines. You do this by pulling vacuum on various points and seeing if the fuel "falls" back down. An example woudl be the fuel in for the filter, pull a vac until you see the fuel and then let it hold that vacuum. Make sure that it does and the fuel doesn't drop back down, if it drops back down then your air leak is somewhere between there and the fuel tank. Keep working your way forward until you find where the leak is.

Hope that helps.

Losing prime

I believe your IP has an air leak. Time to replace the seals!

Please tell me that can be done without replacing the whole pump...

elmo_want_beer said:

Please tell me that can be done without replacing the whole pump...

Click to expand...

Yes it can. Where are you in NC?

TurbineWhine said:

Yes it can. Where are you in NC?

Click to expand...

Though with 151k on the car I'd reccomend sending the pump out for a rebuild.

Shouldn't he check the lines before he jumps to the IP?

I've seen leaky lines cause air bubbles, but not cause the IP to drain out and loose prime

ah, k.

Elmo, take a drive and see Turbinewhine and let him reseal the pump head for you.

oldpoopie said:

Though with 151k on the car I'd reccomend sending the pump out for a rebuild.

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i'm at 148k miles, and it seems with all the BioD and whatnot my IP seals have finally had it. so the questions,

who should i send the IP to for a rebuild?
how much will that cost?
how long will it take?
i'm a semi-qualified mechanic on my TDI, i did my 5th gear but haven't done my own TB. can i remove the IP on my own? if so, is there a post about how it's done?

thanks for the help.

I have heard that replacing the seals is fairly easy and that you can do it yourself.

If you are going to do it on your own, you will need the TB tools. Good .pdf in the articles section on doing the TB.

Line it up properly. Lock the cam. Remove belt as shown in the .pdf.

Remove flexible fuel lines to IP. Remove hard lines from IP to injectors. Unplug electrical connection. Remove three bolts holding the IP sprocket to the IP and remove sprocket. Remove 3 bolts that hold the IP in place.

Empty all the fuel you can from the IP. Double bag the IP with each bag sealed separately so fuel will not leak during shipping. Protect the electrical connector with bubble wrap to keep from breaking during shipping. Pad very well with bubble wrap in box. Must not rattle in box. Put all your contact information in the box with the IP, preferably taped to bubble-wrapped IP.

Ship to: Diesel Fuel Injection Service, 8922 NE Vancouver Way, Portland, OR 97211. 503 285 1213. Call them and tell them it's on the way so they can start a ticket on it.

DFIS will contact you after teardown to tell you what your IP needs to meet all new specs. Can be $400-800, dependent on what they find.

How long? Depends on how busy DFIS is, and method of shipping chosen. If you go UPS ground, it will take forever. USPS priority mail is fast, but they will quarantine your package if there is any diesel leakage or odor.

paramedick:: you only have to do that if you're rebuilding the entire IP right?

If you're just replacing the seals I thought you could leave the TB on. I haven't done it so feel free to correct me (not that you'd hesitate )

puter said:

paramedick:: you only have to do that if you're rebuilding the entire IP right?

If you're just replacing the seals I thought you could leave the TB on. I haven't done it so feel free to correct me (not that you'd hesitate )

Click to expand...

Correct. But that's not what he asked......

paramedick said:

Correct. But that's not what he asked......

Click to expand...

i guess my problem is currently unknown. i only have symptoms, not a diagnosis. i would feel dumb either taking the entire IP out to learn i just need new seals, or putting in new seals myself and realizing that didn't fix my problem.

in response to puter's point... can someone please give a quick description (or link to a formerly discussed thread) of how to replace the seals w/out removing the entire IP.

thanks again to everyone.

MrElo:: I would just do what Oldpoopie says, he knows his ****, that's why I didn't argue when he said I was wrong

now now, I didnt say its Wrong to reseal the pump while its on the car (or off for that matter) I just dont think its cost effective, especially when you are paying someone else to do the work. If you are doing it yourself, then by all means you've got nothing to loose. As for how to reseal while on the car, Dieselgeek sells a kit that includes the 3 seals that you can change (allong with a bunch you cant) as well as a special bolt that keeps everything from falling apart. You must use the special bolt.

UPDATE

Got the IP reprimed, and it held prime without any problems. There is absolutely nothing leaking out of or near the IP itself, or anywhere I can see. I replaced the hose clamps on the fuel filter for good measure, and it's been fine for 2 days now, even though I don't think there was anything wrong with the clamps in the first place. The T-fitting is only a little more than a year old (the old one fell apart while changing the filter)...

It might sound dumb, but I figure that if there is air getting in, and no fuel leaking out that I can see or smell, there must be a leak that develops somewhere along the top-side of something, right?

I just replaced a return line between the injectors and since then our Golf has started nicely.
It did fire up even with the leaking line but it would always stall right after start up, when cold.
Check for leaks at the injectors too, the line I replaced was just damp, it was barely noticeable.

Usually on these VE type systems with suction IP when you have an air leak you have just that-an AIR LEAK, no fuel leakage found. Quite common for the o-rings on the fuel filter "T" fitting to let some air in, but USUALLY you get some bubbles in the line while running.

And most rubber products shrink when coolng - quite a bit. Remember the space shuttle explosion?

So air inleakage problems only on cold mornings usually mean a rubber product above the fuel tank level is shrinking, opening a crack in a line or an O-ring shrinking and opening a gap.

I have read quite a few posts where people have just put on the seals that they can - and have had success.

As someone else pointed out, replacing the rubber lines in the fuel system - especially those above the fuel level - is a very good move, too. And most owners can do this themselves, if they want.

Dan

Here we go again...

Another cold morning, another no-start! I checked the fuel line before cranking, and there was fuel in the line from the filter to the pump... about a 1/2 inch bubble at the top without fuel, and a few tiny little bubbles on the inside of the line itself...

I watched as my wife turned the key and the fuel moved a little bit into the pump, pulled in some air, and then backtracked into the filter...

I've replaced the filter (after the 1st time it lost prime), the t-fitting (about 2 years ago when it fell apart during a fuel filter change), replaced the 0-rings, and put new clamps on all the fuel hoses near the filter. Where oh where is this air leak coming from!! It ONLY happens when it's below 25 degrees outside!!!

Are all the fuel lines from the tank to the engine made of rubber?? I know rubber and biodiesel don't mix very well...

Is it time to add a lift pump?

If I had a VE, I know it is a mod I would do.

Dan

When I replaced my stock fuel filter w/CAT filter unit, the "T" fitting was quite loose in the new housing and I got some sporadic bad starts due to the IP loosing prime. I finally put some real heavy grease around the o-rings and re-set them and its been good for a while now. I probably need some thicker o-rings than what were supplied.

Pull the fuel sending unit and check to see if partial gelling and clogging are your issue.

see this thread

oldpoopie said:

Pull the fuel sending unit and check to see if partial gelling and clogging are your issue.

see this thread

Click to expand...

And this, from "whitedog"...........

Check out situation number five in the first link in my signature.
__________________
How to troubleshoot a car that won't start. Troubleshooting low power by Canadian Grizzly. Doggie Collars for your PD intake retainer needs are still available. Click HERE to learn about why your PD may need a Doggie Collar.

DanG144 said:

Is it time to add a lift pump?
If I had a VE, I know it is a mod I would do.

Click to expand...

i put in a lift pump, and i replaced my stock filter with the FM-100 including side mount heater (see sig). i've had great luck with my winter starts, although this IP seal thing is causing me some mental issues. the car is starting fine... but i'm worried that some time it might get worse all of a sudden.

i'm hoping to have it taken care of ASAP....

Leaking IP should be a concern even if it isnt leaking alot... Think about what is behind that cover.... Thats right, timing belt.
Whats the belt made from? Right again! Rubber!
What likely made the pump leak and is spilling on that nice rubber belt? Biodiesel! Yep, that bio is making that belt all nice and soft and gushy. Of course this can be extreme or super minor, but fuel on the belt is a bad thing.

i had an issue with my b4 passat, car always took half second longer
than "normal" to start, finally was taking several seconds of cranking to
fire then in the final few days took lots of cranking to start and was stalling out just driving down the road.

many bubbles in fuel line when running. checked all the usual leak points in
fuel lines, nothing noted, pulled back timing cover and belt wet with fuel. turned out the pump shaft seal was gone, replaced it and now car starts with touch of the key and no loss of prime. as noted previously, these seals dont always fail completely, depending on fuel quality, temperature etc car may be fine one day, not the next. i seem to remember that in my early diagnosis i replaced the fuel filter and got some improvement but soon was back to losing prime.

i did use a mityvac with a gauge to try and isolate the various components of the fuel system from tank to pump. air leaks can be tough to find, doesnt take much to cause problems. anyway i pulled my IP and replaced all the seals, was not a bad job, if you can do a timing belt its not a whole lot more work.