I've got spark, compression and fuel but no start.

[catamount90]

2003 A4 1.8t.

Car has been running pretty well. A little white smoke from time to time but nothing I was too concerned about after checking compression (140 - 160 cold on all cylinders).

I ran it really low on gas last week while idling in my driveway. Went to go start it again and no start. Filled it up with gas. No start. I put in fresh plugs thinking that maybe they were fouled. No start.

I can small gas so while I know it's getting some gas, I'm not sure about the pressure or quality of the gas it's getting. All ECU-related fuses look good.

Now I'm wondering about the CPS. Will that throw any codes when it goes? Again, it cranks hard but does not start.

Thanks guys!

[diagnosticator]

If you smell gas while cranking, the engine is most likely flooded. To clear the flood, pull the fuel pump relay under the drivers side dash, the first relay on the left in the horizontal row, then crank the engine with the accelerator pedal floored. Don't crank the engine for more than 20 seconds at a time, allow the starter to cool down for a minuet between cranking intervals. Repeat until the engine starts to fire again.

[catamount90]

Well, this has been no-starting for a week now so it's had plenty of time for a flood to clear. Actually, I pulled the plugs yesterday and let it dry out for an entire day. She still won't start.

There is a slight leak around one of my fuel injectors. Just a small pool of fuel that shows itself on the manifold. Could this have something to do with my issues? I guess I'm wondering if there is a GOOD way to measure fuel pressure, and what kind of pressure I should be expecting.

[catamount90]

Hey guys, over a week without starting. Luckily it's my 3rd car so it doesn't NEED to start at the moment but it sure would be nice.

I can smell fuel, I can see spark on all of my coils and I've got good compression. Should I throw a fuel pump at it? New fuel filter? Or CPS?

[Audiguy1234]

I would buy a fuel pressure tester. It's like 32 bucks on amazon or you can find a cheaper on at a local store to check your pressure. Your car might not get the codes for the CPS. Maybe you have broken connection for the CPS.

[CyberPMG]

Fuel pressure for a B6 A4 should be at 4 bar. If you turn on to accessory (not start the car), are you hearing any noises coming from the rear passenger seat? Could be a clogged fule filter and/or the fuel pump going bad. Finding fuel leaks around the injectors is not good. The injector seals are probably going bad and need replacement. You also might want to clean the element in the MAF.

You mentioned replacing the spark plugs. What about replacing the ignition coils?

[Dubsport Inc]

You will get a code for a bad crankshaft position sensor, It will come up something like this... 16705/P0321/000801 - Engine Speed Sensor (G28): Implausible Signal. If the code comes up hit that first!

[Myst420]

I would take the fuel filter off and see if its clogged up.

[catamount90]

Fuel pressure for a B6 A4 should be at 4 bar. If you turn on to accessory (not start the car), are you hearing any noises coming from the rear passenger seat? Could be a clogged fule filter and/or the fuel pump going bad. Finding fuel leaks around the injectors is not good. The injector seals are probably going bad and need replacement. You also might want to clean the element in the MAF.

4 bar, huh? I guess I really need to invest in a fuel pressure gauge.

What about replacing the ignition coils?

I have replaced one of them that was visibly toast. The others were replaced under the campaign.

[catamount90]

I wanted to update this because it's a pet peeve of mine when someone has an issue and then never checks back in let everyone know what the final outcome was. After testing just about everything in sight, including the ECM and main power relay, fuel pressure (good), compression (great), fuel pump (working) and endless other tests I found out that all it needed was a THROTTLE BODY ADAPTATION!!!

I'd never owned a DBW car before so I never even thought about this as a source of the problem. Once I did the adaptation through VAG she fired right up without hesitation. I love a happy ending.

I feel like such an idiot. The more you know!