Hey hey guys,

Trying to tackle another problem on my 2002 A4 quattro 1.8t. After finding and fixing a great handful of problems with this car, another problem has arose that has put me in a pickle. After taking my car on decent drive, about 100 miles or so, and parking it for a few hours, it seems to have lost spark and will no longer start. I started by pulling the fuel line and injectors to verify I was getting fuel, which I was. After running a vagcom test, I had a couple of codes that were never found before.

16712 - Knock Sensor 1 (G61): Signal too high P0328 - 001 - Upper limit exceeded - Intermittent
16395 - Bank 1: Camshaft A (intake): Retarded Setpoint not reached (Over-advanced) P0011 - 002 - Lower Limit Exceeded
16727 - Camshaft Position Sensor (G40): Signal Too High P0343 - 001 - Upper Limit Exceeded

So with this information at hand, I found some information saying that it could be a Cam position sensor gone bad. Since I have a complete head sitting in the garage, I pulled the sensor from that head and installed it on mine to no change. I pulled the valve cover to check the condition of the cam adjuster feet to find both were complete and doing their job properly. Doing more research, I found that the crank position sensor might be the cause of the no-spark and replaced it with a used one from a passat 1.8t I had laying around. No change at all. Is there any information these codes might be telling me that I am missing? I am currently looking at the injector wiring harness as some of that wiring have small cracks and I figure the cam sensor wiring might be grounding on some of those, but have only found damage on the injector wiring and not the cam sensor wiring. After checking voltage at the three cam sensor wires I am getting zero on the ground, 4.98v on the next wire and 10.3v on the last green wire. Could the ECU be at fault for the lower voltage on the last wire or am I in the right direction looking for a short? Even with the cracks, all of the injectors fire properly and very strong. Any direction you guys might know to point me?

 

So small update -

I turned the key on and was checking power to the coil pack wires. I do get 12v on each connector end. When I try to ground out a spark plug to check spark I get nothing. I swapped out the coilpacks to no change. Are the fuse terminals that run the ECU powered with the key? I haven't checked power to the fuses that control engine management yet, what should I expect?

 

Okay, another small update.

I have stripped all of the cracked and hardened tubing from around the fuel injector/cam sensor loom. All of the injectors have cracked and open wires from where the factory tied them to the fuel rail (amazingly still worked fine) but the cam sensor wires are completely fine. No cracks or anything to mention. All of the wires and internals to the heat shrink were all very oily - which is weird. I'm repairing the fuel injector wiring now, but since there isn't a short between the injector wiring and the cam sensor wiring, that takes away my big brilliant idea as to my problem. So what else would cause this? One second it starts strong and a few hours later - no start at all.

 

More info - Here is my complete code list.

VAG-COM Version: Release 311.2-N


Chassis Type: 8E - Audi A4 B6
Scan: 01,02,03,08,09,15,16,17,26,36,37,45,46,55,56,63,76

Address 01 -------------------------------------------------------
Controller: 8E0 909 518 AF
Component: 1.8L R4/5VT G 0001
Coding: 0016701
Shop #: WSC 63251
3 Faults Found:
16727 - Camshaft Position Sensor (G40): Signal too High
P0343 - 001 - Upper Limit Exceeded - Intermittent
18010 - Power Supply Terminal 30: Voltage too Low
P1602 - 002 - Lower Limit Exceeded - Intermittent
19537 - Engine Temperature too Low
P3081 - 008 - Implausible Signal
Readiness: 0110 1101

Address 03 -------------------------------------------------------
Controller: 8E0 614 517 H
Component: ABS/ESP allrad 2328
Coding: 04275
Shop #: WSC 06435
1 Fault Found:
01826 - Sensor for Steering Angle (G85): Supply Voltage Terminal 30
35-00 - -

Address 08 -------------------------------------------------------
Controller: 8E0 820 043 L
Component: A4 Klimaautomat 1016
Coding: 00000
Shop #: WSC 63251
6 Faults Found:
00727 - Potentiometer in Positioning Motor for Defrost Flap (G135)
30-10 - Open or Short to B+ - Intermittent
01274 - Air Flow Flap Positioning Motor (V71)
41-10 - Blocked or No Voltage - Intermittent
00604 - Potentiometer Positioning Motor for Air Flow Flap (G113)
30-10 - Open or Short to B+ - Intermittent
00716 - Air recirculation Flap Positioning Motor (V113)
41-00 - Blocked or No Voltage
00819 - High Pressure Sensor (G65)
07-10 - Signal to Low - Intermittent
01206 - Signal for Duration of Ignition: OFF
27-00 - Implausible Signal

Address 09 -------------------------------------------------------
Controller: 8E0 907 279 E
Component: int. Lastmodul USA 0305
Coding: 00013
Shop #: WSC 63251
1 Fault Found:
01326 - Control Module for Multi-Function Steering Wheel (J453)
49-10 - No Communications - Intermittent

Skipping Address 15-Airbags

Address 16 -------------------------------------------------------
Controller: 8E0 953 549 L
Component: Lenksáulenmodul 0308
Coding: 00041
Shop #: WSC 63251
2 Faults Found:
01333 - Door Control Module: Rear Left (J388)
49-00 - No Communications
01317 - Control Module in Instrument Cluster (J285)
49-10 - No Communications - Intermittent

Address 17 -------------------------------------------------------
Controller: 8E0 920 950 L
Component: KOMBI+WEGFAHRS. RB4 D35
Coding: 03200
Shop #: WSC 00223
WAULC68E53A111162 AUZ6Z0B0197969
1 Fault Found:
01333 - Door Control Module: Rear Left (J388)
49-00 - No Communications

Address 45 -------------------------------------------------------
Controller: 8E0 951 177
Component: Innenraumueberw. 0604
Coding: 00001
Shop #: WSC 00000
No fault code found.

Address 46 -------------------------------------------------------
Controller: 8E0 959 433 BB
Component: Komfortgerát T7B 1311
Coding: 11788
Shop #: WSC 63251
4 Faults Found:
01333 - Door Control Module: Rear Left (J388)
49-00 - No Communications
01134 - Alarm Horn (H12)
49-10 - No Communications - Intermittent
00955 - Key 1
35-10 - - - Intermittent
01562 - Right Rear Door
59-10 - Can't Unlock - Intermittent

Address 55 -------------------------------------------------------
Controller: 4Z7 907 357
Component: dynamische LWR D07
Coding: 00060
Shop #: WSC 63251
2 Faults Found:
01535 - Control Circuit for Right Headlight Range Adjusting Motor (V49)
30-10 - Open or Short to B+ - Intermittent
00774 - Level Control System Sensor: Left Rear (G76)
28-10 - Short to B+ - Intermittent

Address 56 -------------------------------------------------------
Controller: 8E0 035 195 F
Component: symphony II NP2 0051
Coding: 01201
Shop #: WSC 08376
No fault code found.

End -------------------------------------------------------


The power and immobilizer codes are still around from some key issues I had a month or so ago, same with the power (unplugging battery while the car sits). Is there anything else here that would clue somebody in? Should I invest in another set of Crank and Cam sensors in case the two each I have are bad?

 

Okay, maybe this will give somebody some ideas, back on December 10th (When this actually happened) these were the first engine codes given, after clearing them, none have returned, (only the P0343 Cam signal too high comes back)

===================+++++++++++12/10/19++++++++=============================

VAG-COM Version: Release 311.2-N


Chassis Type: 8E - Audi A4 B6
Scan: 01,02,03,08,09,15,16,17,26,36,37,45,46,55,56,63,76

Address 01 -------------------------------------------------------
Controller: 8E0 909 518 AF
Component: 1.8L R4/5VT G 0001
Coding: 0016701
Shop #: WSC 63251
5 Faults Found:
17698 - Coolant Temp Sensor at Radiator Outlet (G83): Signal too Small
P1290 - 002 - Lower Limit Exceeded - Intermittent
16712 - Knock Sensor 1 (G61): Signal too High
P0328 - 001 - Upper Limit Exceeded - Intermittent
16395 - Bank 1: Camshaft A (Intake): Retard Setpoint not Reached (Over-Advanced)
P0011 - 002 - Lower Limit Exceeded
16727 - Camshaft Position Sensor (G40): Signal too High
P0343 - 001 - Upper Limit Exceeded
19537 - Engine Temperature too Low
P3081 - 008 - Implausible Signal
Readiness: 0000 1100



Again, the car ran great, it was only upon trying to start it hours after a drive is when it didn't want to start

 

Without knowing your car, it's possible that many electrical connections have never been touched, and could be compromised by 18 years of heat, cold, humidity, fumes. I usually go through my car about one Saturday a year with a spray can of electrical contact cleaner, disconnecting, spraying, reconnecting just about every one I can reasonably reach. This should include the ground points, even the battery body ground (and obviously battery terminal connections). I had an issue a couple of years ago when my car would go into a lower-power/long crank mode intermittently. The fault code was for an engine speed sensor, but changing that didn't help. But then I noticed that the fault could be triggered by driving over a speed bump in the road. So that implied a bouncing relay contact, and that's what it was- the ECU relay. While I had the ECU box opened anyway, I did the same thing with the ECU and TCU connectors in there, plus the relay and fuse contacts. I don't have any electrical problems at 227K miles, and believe that this periodic contact cleaning helps.

 

So another small update. I have finished fixing the wiring on the fuel injection and have got everything put back nice and tidy. No change, still wont start, not that I honestly expected a fix. It was something that definitely needed to be done even through a small part of me hoped it would just start right up.

This car has 257xxx miles on it, about two or three of which I have added since I bought it (early October?). I've been mending problems on it since I bought it and finally got to a point where I could say nothing was *wrong* with the car (barring some cabin vents, obviously shown in the codes above). I have no way to drive to town to get some contact cleaner, but that certainly something that couldn't hurt anything. I'll catch a ride and see what I can make happen. Because this was so sudden and stopped working like I flipped a switch, I've expected something like a major fuse or something obvious to be wrong, but can find nothing of the sort right now. I'm very surprised that there are no other threads like this on any VW/Audi forum I've come across to try to emulate a fix somebody else can provide.

 

The reason that I suggested doing connector maintenance is from what your fault codes imply: Plenty of them are "signal too low", "signal too high", "no communication", "upper limit exceeded", open or short to B+, etc. Let's say that you have a sensor or actuator with has a pin that's supposed to be grounded. If the ground connection is corroded or broken, then the sensor cannot function properly, and the ECU will read a signal that is way too high (might give an "upper limit exceeded" fault code). This is often what causes the "open or short to B+" fault; a sensor might not actually have it's signal wire shorted to the Battery + terminal, but without the ground connection (Battery - terminal) the output signal will by default rise to the battery voltage. So I would not skip cleaning any ground connections that you can spot.

 

Okay, I have cleaned the negative battery terminal, the ground on the head, and one on the firewall barely to the right of spot behind the head itself. Do you know of any others? I assume there are more (like a ground strap on the transmission somewhere I assume), but the car is under a good few inches of snow right now and I would need a gameplan in this kind of weather, not just fumbling blindly. I don't have the bentley manual yet which I assume would show me what I need to know.

 

Oh wowzers guys,

I pulled the timing belt cover on the head and set up my camera to watch what happens as I turn it over. NO BELT OR CAM GEAR MOVEMENT.

I'm not sure where the problem is without checking under the car, but my crank gear or part of the belt teeth might have sheared off!

I've also confirmed that the alternator belt and serpentine ARE spinning, so it looks like the problem is 100% somewhere with the crank gear or belt at that point. Does that mean a couple of those valves might have been slapped by a piston or two? I don't remember hearing anything like that happening, but I guess it only takes one punch of the starter to do the damage.