940 poor performance

muldersjoerd · Post by **muldersjoerd** » 16 Jul 2014, 05:56

While on holiday in France, my car started performing poorly. I have to pull my caravan/mobile home back home in two weeks, and would really like to have it running better again.

It's a 940 2.3 low turbo, '98, petrol and lpg.
Problems: bad acceleration, poor driving uphill (have to keep very high rpm), irregular idle, and if engine dies because I did not keep rpm high enough, it does not start again.
Engine light is on, but cannot find anyone to read it here.

My workaround untill now: when engine stops, I remove the injectors and start the engine for ten seconds, then plug them in again. When driving, I keep high rpms (which makes my clutch smell bad when I have to drive slowly). Driving on lpg is better than on regular petrol, I figure because it does not wet the spark plugs.

Everything points to a too rich fuel mix. Sparking is ok and I can find no spark leaks (or I don't know how to day this in proper English).

After some measurements:
TPS switch works ok (it works as a switch, not as a variable resistor but I suppose that that's how it should work)
ECT, which was my prime suspect, gives 480 ohm after driving for ten minutes, 840 after two hours of parking. Afaik, all in normal range. I don't know how to test the wire itself though.

Any ideas? Help would be greatly appreciated!

Post by **abscate** » 16 Jul 2014, 07:25

A turbo car that will not idle is often caused by an air hose (induction hose) that has blown off after the turbo. None of the air that blows out reaches the cylinders but the MAF sensor thinks it does so it injects much more fuel than is really needed.

Look at all the hoses and connections carefully and inspect the hoses with a flashlight for splits.

lummert · Post by **lummert** » 16 Jul 2014, 11:45

Have you investigated the fuel pressure regulator vacuum hose for fuel?

muldersjoerd · Post by **muldersjoerd** » 12 Aug 2014, 05:55

Update: finally, while still in France, our car got towed away because it would not start anymore. First, the repairshop replaced the ignition module. Then, they said that the head gasket probably was broken because there was no compression. My insurance company then sent the car back to the Netherlands, to my dealer who will do the rest of the repairment.

Strange thing is, the head gasket has just been replaced, aprox. one year ago. I never noticed any overheating although I had a coolant leak (2 liters were lost) because of a broken radiator. How can a new head gasket blow? I mean, if it was a bad replacement, it probably had blown much earlier. But if it was good, then what makes it blow? As far as my knowledge goes, a head gasket blows either with age or with overheating?

lummert · Post by **lummert** » 12 Aug 2014, 06:48

Did it overheat?

muldersjoerd · Post by **muldersjoerd** » 12 Aug 2014, 06:53

I'm 99% sure it did not overheat, not that I saw. No smoke from the engine, no meter in the red, etc.