prslespaul

I bought an 2003 Audi A4 1.8T 5spd. Car started right up at first for about a month. After that, the car wouldn't start unless I hit the gas pedal. When it was warm it would start with no gas pedal but it eventually got harder and harder to start and the longer it sat the harder it would be to start. Once the car was up and running it ran perfect and had plenty of power. Well, it sat for 3 days then wouldn't start at all. I tried and tried and nothing. I checked fuel pressure and was getting 55 psi to the rail, and all 4 plugs are getting spark. I hooked it up to a vag-com and the only engine fault that was serious that I could see was as listed below:

16705 - Engine Speed Sensor (G28): Implausible Signal
P0321 - 008 - Implausible Signal

I thought this would make it not start and the symptoms seem to fit minus the having to hit the gas pedal to get it to start. Now weirdly, I have read that hitting the gas pedal causes the injectors to turn off and cause a dry start? Strange.


Either way, i bought a new crankshaft sensor and replaced the faulty one. I reset the code and tried to start it.. Same old story, no start. I am getting so frustrated with this car and it has been sitting here for 3 months and I would like to drive it. Could someone please help me. Any help would be appreciated. Thanks!

MaxD

My car had a bad crank position sensor, and experienced progressively harder starts, but the problem was usually worst if you tried to restart a short time after driving. Sitting seemed to clear the problem up.

The code for my CPS was:

1 Fault Found:
16706 - Engine Speed Sensor (G28): No Signal
P0322 - 004 - No Signal/Communication - Intermittent - MIL ON

Similar, but not the same as your error codes. Did you check for codes after it wouldn't restart following the CPS replacement?

prslespaul

I put a new crank shaft sensor in, I reset the code. Turned it over and within 5 minutes the code for the sensor threw again. I am lost on what to do.. Harness and wires all the way to the ECU look good.

s4master1

do you get RPM readings while cranking?
when the engine cranks without firing for more than 30 turns the ecm by default sets a fault for faulty crank sensor.
we see this quite a lot when fuel pumps fail, check your fuel pressure again while crtanking.

prslespaul

Where am I checking rpm readings at? On the tach or vag-com? And if it's accessible on the vag-com; how do I do it?

That is interesting about the speed sensor automatically coming on after 30 cranks, I will check my fuel pressure again. I can hear the fuel pump turn on when I turn the ignition on does that mean that it still can not be bad?

600whpA4

When starting a DBW A4, the throttle pedal isn't doing anything to the TB.

lyleswk

Sorry, gotta ask and please don't take offense. You replaced the sensor mounted just behind the oil filter housing, right?

Also, VAGCOM codes are different, but reflect the same problem. One is intermittent and does not set the MIL, the other is no signal and sets the MIL. Mine went from the intermittent code to the no signal code when my ESS gave out completely.

prslespaul

It opens the throttle giving it more air at the very least. Either way it would not start without hitting giving it gas.

prslespaul

And yes i replaced the correct sensor.

prslespaul

Bump?