Engine Revs High on Warm Start?

Hello everyone,

I have an Audi 80 B4 TDI with 90 horsepower.
He's been having a problem for a few days now:

Cold start, excellent!!

'When starting the engine in warm conditions, it revs up to approximately 2000 RPM for about 2 seconds. At that point, I can't do anything, meaning I can't accelerate. Then, it jerks and returns to normal operation.'
If the engine is left idle for a few hours, everything is fine again.
Once, after that, I also experienced a significant performance loss, or rather, very little performance.
Engine on and off, power restored.

I don't know what to do.
Could this be related to the engine temperature or the outside temperature?

I hope you can help me.

Audi_B4_TDI wrote:

Hello everyone, I have an Audi 80 B4 TDI with 90 horsepower. He's been having a problem for a few days now: Cold start, excellent!! "When starting the engine in warm conditions, it revs up to approximately 2000 RPM for about 2 seconds. At that point, I can't do anything, meaning I can't accelerate. Then, it jerks and returns to normal operation." If the engine is left idle for a few hours, everything is fine again. Once, after that, I also experienced a significant performance loss, or rather, very little performance. Engine on and off, power restored. I don't know what to do. Could this be related to the engine temperature or the outside temperature? I hope you can help me.

Hello,

The high RPM after starting sounds like a faulty engine temperature sensor. It's possible that yours is sometimes sending values for extremely low temperatures, which increases the engine speed. -> Check the sensor for faults or use a diagnostic system to verify the plausibility of the engine temperature reading.

Best regards, Rainer.

hello rainer,

Thank you for your reply.
Where can I find this?
Is that the same sensor that also displays the engine temperature on the dashboard?
He's actually okay.

Sure, here is the translation of the text from German to English:

'Hello'
eric

Is that the same one that also displays the engine temperature on the dashboard?
He is actually okay.

The motor and the instrument cluster have their own sensors. However, both are housed in the same casing!

Therefore, the instrument cluster might show everything is fine, but the engine is still receiving bad fuel.

CU Gremlin.

Hello everyone!!!
'Thank you very much!'

Where can I find this temperature sensor?

Audi_B4_TDI wrote:

hello everyone!!! "Thank you very much!" Where can I find this temperature sensor?

Usually, it's located on the cylinder head.

I had the same problem.

In my case, the performance drop was accompanied by a flickering light bulb.

It was a needle injection system.

Just a tap and it started working again.