strange happenings

DJMCA

RMS Regular
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1,259
Getting some real weird issues with my 03 passat pd tdi

1 - starting and driving away, (always in 1st or 2nd) on occasion it just dies, absolutely nothing, no power, completely flat, unless you push the clutch in and give it a blip/rev. Then its fine, doesnt miss a beat.

2 - starting and driving away, on occasion (so far always in 2nd) theres a real bad grinding/crunching mechanical noise and car will basically lose power, thud to a halt and stall. Again if you push the clutch in before it stalls it will clear.

The faults are seperate but starting to happen more often.

Only work carried out recently is replacing the steering rack. I have a simple obd code reader but only code showing is 0778 steering angle sensor fault.

Any help much appreciated.
 

greyfloppyhat

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1,548
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Tassagh
What engine is it?

Can't think of anything that ties point 1 & 2 together into one root cause.

When was the last time it was serviced, just to rule out basic things.

Injector loom ever been checked or replaced?
 

DJMCA

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DJMCA
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Its a pd avb and i service it every 7-8k religiously. Injectors arent direct rail, they are internal on the pd. I always use diesel additive and good quality diesel.

Yeah its a real strange one, cant even explain the noise properly! Will need to get it on to diagnostics i suppose and see if any codes are showing
 

greyfloppyhat

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Injectors arent direct rail, they are internal on the pd.
Exactly why the loom needs checked! The wiring is under a lot pressure where it is located in there with the high temps and temp cycles etc.

At this age replacing that loom would be preventive maintenance in my eyes. Wipe the valve cover off and take a look

The grinding noise is a wierd one, not sure there
 

DJMCA

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DJMCA
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Cheers, worth a look anyway. Ive anothe set of injectors to go in before a remap so would be worth doing at the same time
 

DavyC

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433
Not sure about the grinding noises but sounds like the steering wheel could be out of sync with the rack now.

If you turned the steering wheel a whole turn before connecting it back to the rack, then the ECU is getting mixed messages from the steering angle sensor and abs sensors. For example, when driving straight the ABS sensors would show equal signals, yet your steering angle sensor will say you're cornering.... Which has made me wonder.. is your 'crunching noise' the ABS / traction control kicking in? As you're driving straight, the ECU thinks you're cornering and the inside wheel is spinning, so activates traction control.

I think you need to try reattaching the column to the rack again. Probably just try one turn in either direction from where you have it now and if that doesn't work try one turn in the other direction.
 
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DJMCA

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DJMCA
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Might make sense @DavyC, i will have a look at it tomorrow. Noise has only started since i changed the rack

Just trying to get ideas before i start spending £££ on changing throttle position sensors, n75 valves and injector loom.
 

HairyPotter

RMS Regular
Messages
118
Drives
Exeo
had a similar issue in my old 2003 Ibiza 1.9 PD ASZ (dieing out after a couple of hundred yards)
changed the crank position sensor and it resolved it.
although i do think it showed a related cam sensor error when the garage scanned it
 

colin84

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3,899
For the 1st problem, try changing your fuel filter for all it costs.
 

greyfloppyhat

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I'd a passat have an issue where it would randomly misfire, and the owner said pushing the cutch and give the accelerator a good blip would solve it. Turned out it was a broken connection in that loop, and the blip just would just help seat the wires together enough temporarily to fix it
 

DJMCA

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DJMCA
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Thanks all, will get it on to the computer this week, see what showing up.

When it dies i can hear a beeping behind the dash somewhere so i assume its an electrical problem
 

DJMCA

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DJMCA
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For the sake of closing out a thread to help others searching the net with the same problem (and my OCD).

Problem sorted (hopefully!). Stuck it on to Vagcom and found the steering to be showing -360 degrees when the steering wheel and wheels were straight. Obviously i had turned the steering wheel at some point whilst doing the rack....duh!!!

For some reason the sensor wouldnt reset through the software so i took it off at the bottom of the column where the knuckle is on to the rack and turned the steering wheel 360 degrees to the left (1 full turn). Connected back up, cleared the fault and check the degree angle. Job done, so far so good.

I assume the abs and traction control were cutting in as the car throught the wheels were spinning/loosing traction under acceleration as suggested by @DavyC above

Thanks all for the ideas and advice.
 
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