01 A4 1.8T Quattro Manual won't start

[eurotecknik]

hey guys,
As the title states my car won't start.
I have many hours put in trouble shooting but I still need help.
New spark plugs. It has spark. (checked the old-fashioned way)
There is fuel going to all 4 cylinders. (recently sent my injectors to WitchHunter performance to have them serviced. Now all 4 are in excellent working condition)
New walbro fuel pump.

Latest codes are:
VCDS Version: Release 10.6.3 (x64)
Data version: 20101206

Thursday,13,January,2011,12:56:56:36755

Chassis Type: 8D - Audi A4 B5
Scan: 01 02 03 08 15 16 17 25 35 37 45 55 56 57 67 75 76 77

-------------------------------------------------------------------------------
Address 01: Engine Labels: 058-906-018-ATW.lbl
Part No: 4B0 906 018 M
Component: 1.8L R4/5VT G 0003
Coding: 16201
Shop #: WSC 06435
VCID: 2B481377F383

3 Faults Found:
17987 - Throttle Actuator (J338): Adaptation Not Started
P1579 - 35-00 - -
17956 - Boost Pressure Regulation Valve (N75): Open Circuit
P1548 - 35-10 - - - Intermittent
18010 - Power Supply Terminal 30: Voltage too Low
P1602 - 35-00 - -
Readiness: 0110 1101

Obviously, I cannot perform throttle body adaptation. When I try to go into Group 060 vag-cam gives me an error message.

Please help a brother out! Any insight into the situation?

[PourBoi-Jay]

Try jumping it.....Due to the cold weather, an older battery won't produce a strong enough spark to start. I'm experiencing the same issues......Give that shot

[eurotecknik]

Try jumping it.....Due to the cold weather, an older battery won't produce a strong enough spark to start. I'm experiencing the same issues......Give that shot

^^^Thanks for the recommendation. I have tried jumping it. Engine turns normally and sometimes sounds like it wants to start, but never does.
BTW, where is "Mike@Ringer-Racing.com" ?

[eurotecknik]

bump

[eurotecknik]

bump

[eurotecknik]

BUMP

[DaveD]

Wish I could help man, shoot a PM to 04.5 GLI, he is one of the best technicians I know

[Charlescrs6]

Plug to the N75 is most likely unplugged, or the wires are corroded. Although I imagine your car should start with this.

[eurotecknik]

All right, I will PM 04.5 GLI. Thanks!

I know this is really a weird problem.
I really don't feel like towing the car to a mechanic and, not just any mechanic, and dealing with expensive repairs while I am capable of doing all kind of repairs on the 1.8T engine.

[un1ko]

Good luck! Hope you get your car running soon!

[04.5 GLI]

thanks dave!

so heres a couple tests that you can check with your vag com. if the car cranks normal and sounds like its trying to start it could be 1 of these.

crank position sensor. this with affect your starting and ignition cycle. i dont remember which mvb is for the crank sensor...

also do you have push in coils or bolt down coils. if you have bolt down coils you have an ignition output stage on the airbox. if this goes bad you will either have a dead misfire or no start condition.

also with you dtcs stored in the ecm a power supply relay will cause your issue. as per the throttle position sensor it could be a faulty throttle body or ecm. you can check this by going into the mvb and check the values. your gas pedal and throttle body work on opposite values of 100%. once again the early a4 mvb im not sure about. but if you find a mvb with multiple fields 1 being 90--100% and the other being near 0. when pressing the gas pedal slowly the values will change going to the opposite percentage. this is a way of diaging your throttle body and pedal.

if i can think of anything else ill post it up. and any issue you can pm me. just be aware im not on all the time so my response may lack some.

good luck with car.


you should also look into your fuse panel on the drivers side and also near the ecm. some of the audis have a fuse near the ecm for ignition voltage.

[eurotecknik]

thanks dave!

so heres a couple tests that you can check with your vag com. if the car cranks normal and sounds like its trying to start it could be 1 of these.

crank position sensor. this with affect your starting and ignition cycle. i dont remember which mvb is for the crank sensor...

also do you have push in coils or bolt down coils. if you have bolt down coils you have an ignition output stage on the airbox. if this goes bad you will either have a dead misfire or no start condition.

also with you dtcs stored in the ecm a power supply relay will cause your issue. as per the throttle position sensor it could be a faulty throttle body or ecm. you can check this by going into the mvb and check the values. your gas pedal and throttle body work on opposite values of 100%. once again the early a4 mvb im not sure about. but if you find a mvb with multiple fields 1 being 90--100% and the other being near 0. when pressing the gas pedal slowly the values will change going to the opposite percentage. this is a way of diaging your throttle body and pedal.

if i can think of anything else ill post it up. and any issue you can pm me. just be aware im not on all the time so my response may lack some.

good luck with car.


you should also look into your fuse panel on the drivers side and also near the ecm. some of the audis have a fuse near the ecm for ignition voltage.

Thanks for your reply 04.5 GLI,

Crank position sensor is brand new and I was able to fire up the car with the new sensor a couple of months back. Now, it won't start.

"ignition output stage on the airbox", I think what you are talking about here is "ICM" which only AEB engines have. That doesn't apply to me.

I have 2 working ECU's and the car won't start.

"power supply relay" as far as that, I don't know where it is located and how to check it.

Throttle body is brand new out of the box. And I know what you mean by checking the throttle body using vag-cam and the gas pedal. In fact, it is #054 for me on vag-cam.

My only concern is the wiring harness because the insulation around the coil-packs melted not too long before the car stopped running. Also the wires around the injectors. I have put electrical tape on every broken wire. I used to have fuse #30 blow up on my everytime I turn the ignition key on. Now that is fixed. I am actively looking for a replacement AWM engine wiring harness on daily bases. After that is taken care of my last resort is to turn the car to an audi mechanic at a shop.

Also, fuel pump is new. I have tested for spark and fuel and both seem to be just fine.

Any other ideas will be greatly appriciated. Thanks

[04.5 GLI]

sorry for the delay on response.

your power supply relay is in the ecm box. if your harness melted then there is a possibility that that you popped a fuse or relay. i would need your vin to get wiring diagrams.

[eurotecknik]

ok, what happens when the power supply relay is popped? How do I know?

Update: Now there are absolutely no codes. Took me swapping ECU's, batteries and Vag-com to try to wake up that brand new throttle body

By the way, the car still won't start

And:04.5 GLI, I will give you the VIN number as soon as I figure out why I cant send PM's here.

[beemercer]

as soon as I figure out why I cant send PM's here.

I believe you need 25 posts minimum to PM