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Discussion Starter #1
So I finally got what I wanted . At TDI VW. Its a 97 Passat. Recently I put some time into servicing it. One of the repairs was to fix the leaking Fuel pump seals. That seemed to go rather easily and well.

The other day I decided to clean the engine. It was filthy because the fuel pump had been leaking for a long time before I got it and the diesel burning off on the engine ate away all the foam under the cover and made a lovely mess of everything. It came out sparkling clean with Purple cleaner... and a hose... only snag is.. it is now difficult to start, takes about 10 cranks every time, hot or cold and has lost all power all the time.

The engine light isn't on and turning it on or off doesn't improve the power loss. . I've disconnected as many wire plugs as I can see and sprayed them with electrical cleaner.. no result. Wiggled a few vacuum lines here and there but its still struggling. The idle seems fine. Power kicks in a bit only around 3500 rpm. I have noticed that when I come to a stop or let of quickly on the pedal the rpms drop a little lower then pick back up.. but that could be normal.

I'm assuming the turbo isn't kicking in, but not sure how washing the car could kill it... Any help would be really appreciated.. my driveway is long and steep.. I barely make it up now.
Thanks
 

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Which fuel pump seal did you replace? The top one is nothing but the middle one is the quantity adjuster. You have to use a vag com to set its position. But if it didn't happen until after you cleaned the engine then something else is wrong.
 

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Hi John,
Thanks for the response and Happy Thanksgiving. I replaced the front O ring seal and the fuel filter a couple weeks ago. All was fine running-wise but it still leaked from the top and middle seals. Ordered them and replaced top and middle just before washing the engine.. SO.. perhaps that was the culprit.

I'm waiting for my VagCom cable to arrive.. I just got the program the other day. Never used it. this be a tough fix? I followed the step-by-step for replacing the seals here: http://oursazlife.blogspot.com/2009/08/alh-tdi-injection-quantity-seals.html

It didn't seem to mention any potential for messing up the power/turbo other than keeping everything marked and re-aligned..
 

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Discussion Starter #5
OK, so to answer my own question. This website is amazingly laid out and I have to thank all involved. I found the link to the injection quantity adjustment on this site through google. It seems relatively straightforward. Once I get the Vagcom cable. Understanding the tapping the top of the fuel pump is like twisting a distributor was a little bizarre.
 

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OK, I believe that is your problem.

Physically indexing the quantity adjuster is just to get it to where it will start after removal.

You must fine tune it like you said and as shown in this writeup: http://www.myturbodiesel.com/1000q_how_to/multi/IQadjusthammermod.htm , to get it to a normal range if it's out of the physical limit that it can adjust. But before you do anything, warm up the car and check the software IQ. If it's in the normal range it may not be the cause.

Washing the engine could also have caused the problem. Some water pools into an electrical connector and something shorts out.

Check all your electrical wires including the ones under the battery, on top of the starter, and underneath the air box for chafing, cracking, or rubbing. I lost an injection pump because of bad wiring and it's possible that cleaning it could have disturbed a wire.

If you go through the low power fix article it should at least get you started to where you can either fix the problem or give more details to identify what the problem could be.
 

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Discussion Starter #8
Thanks for the details. I'm going to wait for the vagcom cable, at least its running for now. I did go through every visible electric connection I could see (will check those mentioned above too) I opened them up and shot them with electrical cleaner. I haven't check for a boost leak. I read the writeup in the low power link, but was a little confused as to a good place to run air for the check. I have the compressor etc needed, any preferred vacuum line to hook into?
 

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Anywhere along the intake air path will be fine. Some of the vacuum lines only go between the solenoid and the turbo or something like that. Make sure to regulate the pressure down to about 5psi.
 

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Discussion Starter #11
OK Finally Got to it

So. Chittychittybangbang was right. Sorry for the delay. Its been raining and I've been waiting for the VagCom cable to arrive. I bought the Ebay VagCom cable and used the free trial version of VagCom. Total $20.

The mgr/str reading was 15.8. So after trying to tweak it with the laptop I realised I had to get under the hood and tap it to the right. Came back in and after a few back and forth trips I managed to get it to 3.8. Runs like a charm and I'm totally ecstatic:ban First time plugging into my car with a laptop and it was surprising easy. I now know how easy it was for the shop to nail me for $200 every time I took my Saab in to be checked.

I cleared a couple engine codes and that was it. I did have trouble with the cable once..."too many communications..." but despite all the online chat about how it is because of the cheaper cable, the fix was simple. I turned off the car and restarted by opening the VagCom and making sure the key ignition was turned on but the car wasn't running.

Other things to be sure of. Your computer's USB com port must be set to the same one that you choose in Vag. Anyone with my problem or VagCom problems can visit an amazingly good Audi link http://www.audizine.com/forum/showthread.php?t=158766 It walks you through the entire setup process. Make sure you install the drivers from the CD.. beforehand.
 
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