Audi A4 1.9TDI 1Z 1996 engine dies

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Sun 8 Apr 2007 08:00
Audi A4 1.9TDI 1Z 1996 engine dies - Dan How
It has been reliable for 180,000 miles, but needed gearbox rebuild. Recent comprehensive service inc cam belt. Speedo & odo dead for a while. Specialist VW Audi garage suggested replace in a year's time, hopefully OK until then.

It starts and dies after 2 secs, key warning light flashes, no change with spare key. Using accelerator, it appears something switches it off. If immobiliser, can it be bypassed?

I am an electronics engineer, but little info available. Is it a scrapper or might it be a poor connection or an easily replaced part?

If a scrapper, what would you replace it with? I have up to £7K and need reliability and longevity. Is the extra cost worth it for an Audi. Should I buy a Mondeo TDi?
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Sun 8 Apr 2007 09:29
Audi A4 1.9TDI 1Z 1996 engine dies - George Porge
Why don't you have the car scanned for faults by a mobile tech? If it shows up as an immob fault the chances are its the key reader pickup on the ignition barrel. Its unlikely that both keys have died together.

Where about in the country are you? Someone will be able to recommend a tech to help you.
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Sun 8 Apr 2007 11:09
Audi A4 1.9TDI 1Z 1996 engine dies - Dan How
I am just west of Carlisle in Cumbria. Good idea about mobile tech, thanks.

Considering that the speedo and odometer packed up a while ago and I was told by the local VAG parts department that replacing the instruments would require me to get the key recognition programmed, I gave the dash a good thumping and it works at the moment. Immediately before hitting it the problem still existed.

Thanks for hint about sensor on the barrel, I don't think the Haynes manual mentions it. Maybe the problem isn't going to be as expensive as I thought.
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Sun 8 Apr 2007 11:14
Audi A4 1.9TDI 1Z 1996 engine dies - adverse camber
very common fault on these is the loop wire that picks up the chip signal from the key for the immobiliser. given your little key light comes on that would be my guess.

Its a quick thing to replace and not expensive. But get the codes read to confirm - the error message doesnt say the loop is knackered - just something about trying to start and immobiliser activated,.

while you are at it the ignition switch is another common problem, can also causenon starting. any probs getting the key in and out?
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Sun 8 Apr 2007 14:14
Audi A4 1.9TDI 1Z 1996 engine dies - Screwloose
Dan

Yes; as said, it is the immobilizer. Quite common. While you're waiting for the VW Parts to re-open, pop off the coulumn shrouds and eyeball a black plastic annular ring around the lock barrel.

Follow its single shielded cable back into the dash and you'll find that it terminates in a tiny six-pin plug. Remove that plug [and it's twin] from the little immobilizer box and clean them with proprietory contact cleaner. Often it's only contamination on the gold pins that causes this problem.

If necessary; the black plastic immob unit covering the stop solenoid in the back of the pump can be removed. Can't say how on here; but there's brutality and a sharp little chisel involved. I've done dozens and it takes about five minutes now.
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Mon 9 Apr 2007 00:39
Audi A4 1.9TDI 1Z 1996 engine dies - Dan How
It certainly looks like a poor connection problem. I thumped the dash once again. The odometer is now displaying for the first time in a year and the tacho went round full scale into the clock! The car starts every time at the moment- but I know I need to get those connectors sorted out or it will happen again.

Thanks for the advice everyone, it is much appreciated.
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