Hey all,
I always enjoy hearing comments/advice from my fellow forum members - sometimes over what the stealership has to say! lol Okay, so here it goes with as much information as I currently have/know:

On Friday, Oct 1, my 2001 Audi A6Q 2.7L died on me while on campus. I ended up having to get it towed home, where it now sits dead in my driveway. It started up that morning with absolutely no problems; the weather was around 60F. I let the car idle for 5+ mins. as I always do (it's a bi-turbo) and drove to school. Went to two classes (2 hours worth of sit time), went to car, started up, drove down to the other end of campus, parked the car, went inside to make up a test (15-20 mins. tops) came out, used the FOB, turned and started the car, it cranked, turned over and started VERY weak (when I say weak, I mean like putting and coughing for air to breathe for its life) and then died after < 15 secs. Restart attempt #2: it cranked, turned over, started, coughed for it's life again, and this time died after only 8-10 secs. Restart attempt #3: it cranked (and cranked good and strong) but would not turn over and start. Now, a car needs 3 things to start and run. 1) Fuel. 2) Spark 3) Air.

Facts:
#1 thing I did: Pull out my OBDII and pull any codes. None.
3/4 Tank of Gas (93 Octane - purchased about 3 days beforehand) She has an APR 93-Octane High Performance Chip. She is and was in Chip mode.
Battery is between 12V-14V. About 12V while cranking. It is a rather new (< 1 year old) OEM Audi Battery.
While waiting for tow truck, checked all of the fuses (fuel pump, fuel pump relay, etc.) in the interior fuse panel as well as any significant ones that would affect starting the car in the power distribution box (engine bay) - all were in excellent shape. Notice I say excellent, not just good. Most of them are brand new. Each fuse slot was double checked to ensure the right ampage fuse was in the right slot.
The car was not even attempted to be jumped as I know it is not a battery issue. (> 12V cranking, all accessories work strong/bright, and she cranks like she owns the world - good & strong.) haha
Within the last 10k miles, I have replaced/the parts are rather new:
Fuel Filter
Due to misfires galore: I went up & beyond and replaced all 6 spark plugs (OEM & gapped correctly), 6 coils, (not the wires though), and 2 ICMs (Ignition Control Modules)
Brand new MAF sensor
New air filter (Every 10-15k miles)
I am due for an oil change though it's been about 6k miles (Mobil 1 Fully Syn.)

If I think of any other important helpful information I will edit this post.

So, I have it towed home and instantly think to check the fuel pump. I get my father to listen to the fuel pump, with the back seat pulled and the FP cover removed. I turn the car to ON (not start). He could neither feel nor hear the FP priming or running. It wasn't doing anything. So now I think "Okay, great. The FP finally died on me. That's a nice $300 out of my pocket " However, we decide the test the power going to the FP with a multimeter and with the car turned to ON, we could barely get a reading. I pulled out my Bentley manual and have been clueless; starring at the wiring diagrams, etc. b/c I'm no electrician lol My father also got the idea to test the fuel pump fuse socket with the multimeter and it seems like he had trouble getting anything (a reading) there as well.

Can you guys help me, please? You're brilliant automotive/mechanic brains & intelligence will be highly appreciated! I'm getting stuck here as to what to do next. In the morning I'm going to call my guy down at the dealership and run it past him, see what he thinks. He knows I know a lot about and work on my own cars and he likes that, so he never tries to B.S. me. Or so I think Stealers can never truly be trusted haha

If you guys need any more information / questions / etc. just ask! I'll recheck this thread often to look for updates/comments.

Thank you so much!

- Ben -

 

Ben,

Test #1 - try measuring the voltage at the pump while cranking the engine.

Test #2 - straight wire the fuel pump and see if the car starts. Just run a wire from the +12v post on the battery to the fuel pump positive input and ground the ground. The pump should start pumping and you should be able to hear it and, if you can test the pressure, it should have 40 psi f pressure. The car should run. If all this works out, you then have to trace the wiring (as you and your Dad started to do) backwards one connection at a time to find the bad connection or bad section of wire. Most likely it is a relay, not a fuse or a bad section of wiring, nut you never can tell.

Bob

 

Thanks for the input bob! I did forget to mention we have already tested the FP relay under the dash with a 12v source and it works perfect. I will try to straight wire it and see what happens.

I always thought the FP primed when the car was turned to ON to ensure fuel was pumped to the injectors during START but for what I've been hearing, this isn't true. It is only energized when cranking/running?

 

Thank you for all of your input! I am 99.9% sure now that it is the FP itself. I just went out to straight wire the pump up to the battery and I figured "Ah what the heck, one more time I'll just try to start it." I reconnected the power source to the FP, turned the key and it started right up. Let it idle for about 3-4 mins and it didn't die out on me. Then I shut her down, let her sit for a minute or two, restarted her with success, she ran for about 30 secs and died. Restarted, ran for about 10-15 secs and died. Would you guys agree it is just the pump and not the wiring source, etc. before I go spend $300 on a new pump? lol

 

Sounds like its a wire problem not the pump its self from what I have read. when it gets power it seems like it works fine. I'd check the wiring and find where the problem is.

It's not getting power, have you checked to make sure the FP has a solid ground.

I'd take a Volt meter start at the relay and check the power wire to ground about ever foot for power to find the problem. Just a suggestion not a surefire fix. good luck

 

Thanks twistedfreedom for the advice

 

I would still be very suspect of the pump itself I have seen many with these types of symptoms as they will run for a short period and then lock up and if you let them sit a while they will run for a short period again.