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Right, after weeks and weeks of waiting for new parts I still have this fluctuating idle problem in Park and Neutral whilst loosing all my fuel through exhaust.

Here is what I have done so far:

Cleaned throttle body

Adjusted throttle cable

Replaced TPS sensor

Replaced MAF sensor

Replaced air filter

Replaced leads

Replaced spark plugs

Cleaned idle contol valve and housing

Cleaned all connectors and plugs

Cleaned PCV valve

Replaced EGR filter

I am really running out of ideas on what to do next. The engine management light is not on and I have done a diagnostic check which comes up as no faults?

The only other thing I have not done is replaced the fuel filter, but I cant really see it causing all this grief. It is overfueling because the engine is over compensating for something but I just dont know what!

Any advise would be much appreciated to cure this bloody fluctuating idle and overfueling.

Cheers.

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Have you checked the coolant temperature sensor/wiring to the ECU ( sorry don't know your year but should be located on top of intake manifold below the ISC valve because if this is faulty and telling the ECU the engine is constantly cold the ECU will adjust the fueling to cold start/running mode.

One way of confirming it's working is to start the car from cold whereupon the engine speed is normally 1200/1300 rpm as the engine warms up the revs will gradually fall to a normal warm idle speed of around 650 rpm.

Also check the cold start injector time switch/wiring ( location as above)

Too high fuel pressure is another option or leaking injectors ( unlikely ) or incorrect injector opening pulse timing ( you need a scope to check this is correct).

The fuel filter I would discount as the cause as they generally clog up and restrict fuel flow causing underfueling/weak mixture but as a service item I would replace if it's due.

If you email all the details to this guy he may offer a solution

carmexhelp@aol.com

Cheers,

Steve

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Just remembered another possible cause of fluctuating idle speed have you checked the wiring loom over the left boot hinge for wiring damage as it causes all sorts of weird problems including yours.

Plenty of info on here as to what to do to repair and it doesn't cost anything to check.

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Right, after weeks and weeks of waiting for new parts I still have this fluctuating idle problem in Park and Neutral whilst loosing all my fuel through exhaust.

Here is what I have done so far:

Cleaned throttle body

Adjusted throttle cable

Replaced TPS sensor

Replaced MAF sensor

Replaced air filter

Replaced leads

Replaced spark plugs

Cleaned idle contol valve and housing

Cleaned all connectors and plugs

Cleaned PCV valve

Replaced EGR filter

I am really running out of ideas on what to do next. The engine management light is not on and I have done a diagnostic check which comes up as no faults?

The only other thing I have not done is replaced the fuel filter, but I cant really see it causing all this grief. It is overfueling because the engine is over compensating for something but I just dont know what!

Any advise would be much appreciated to cure this bloody fluctuating idle and overfueling.

Cheers.

Hi,have u set up the TPS sensor.
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