1991 2.0 940t starting issues getting worse.

[Mickyfinn121]

I've had the car 2 months now and when it starts it runs on 3 cylinders for up to 30 seconds then runs fine after that. But recently it has started to turn over for up to a 60 seconds before starting on 3 cylinders then running fine. But today it turned over for a fair while then ran on 2 cylinders then 3 then ran fine seems to be getting rapidly worse as the days go on. It had a full service 500 miles ago and that included new ht leads and new sparkplugs. Bit worryed soon its going to either not start or turn over so long the battery will go flat 😂 cheers in advance.

[360beast]

Do these have a cold start injector?

The one on my first 360 went and it would start on 3 cylinders and run like that for about 10 seconds before the 4th one kicked in.

[Mickyfinn121]

Originally Posted by 360beast

Do these have a good start injector?

The one on my first 360 went and it would start on 3 cylinders and run like that for about 10 seconds before the 4th one kicked in.

Not sure on what injectors are in it to be honest new to this car 😞

[Laird Scooby]

Did the full service include a fuel filter?

Another thing you could try is cleaning the throttle body and Air Idle Control Valve (AICV) and also, when you get down to about 1/4 tank, add 2L of meths to the tank - Toolstation are the best value on that :

https://www.toolstation.com/shop/Pai...+Spirit/p99550

Short version is it emulsifies condensation in the fuel tank that has collected and settles at the bottom of the tank when the car is not being used. In effect, this gets drawn through the pumps first on the next cold start but the meths emulsifies with it so it can burn off with the petrol.

Some cars of your age had a cold start injector, others didn't. Also try "flicking the starter" on the key, turn the key to position 2 (ignition warning lights on) then "flick" it into the start position so the starter just turns a little and release. You should hear the fuel pumps run for a couple of seconds then try it again.

These are all things that cost very little to try but will give a lot of useful clues as to the exact nature of the problem.

[mocambique-amazone]

Shouldn't be with cold start injector.
Head gasket.
Check the plugs. You will see 1 different, light yellow coated.
Whow many miles the car has on his speedo?

A CO- test will be not good enough. The B230F are prone to fail with head gasket and zero CO inside the coolant.
Do the next drive with open water system and close the system when you did shot of the engine. This will result in a underpressure inside the coolant system. If the car will start more easy next day you know that the head gasket is gone.
Good luck, Kay

[Mickyfinn121]

Originally Posted by mocambique-amazone

Shouldn't be with cold start injector.
Head gasket.
Check the plugs. You will see 1 different, light yellow coated.
Whow many miles the car has on his speedo?

A CO- test will be not good enough. The B230F are prone to fail with head gasket and zero CO inside the coolant.
Do the next drive with open water system and close the system when you did shot of the engine. This will result in a underpressure inside the coolant system. If the car will start more easy next day you know that the head gasket is gone.
Good luck, Kay

It has 80.000 on the clock and when i serviced it all filters was changed to. Iv pressure tested all cylinders and they all above standard but not sure if that would test head gasket. Also done a coolant change and that seemed fine.

[Laird Scooby]

What gap did you use for the plugs?

Also worth checking, Crank Position Sensor - mine gave these symptoms shortly before failing. Check the RSR (Radio Suppression Relay) and fuel pump relay.

Also double check the terminals on the lead end of the plugs. In the past i've had those come loose on new plugs so the HT leads are just sitting on top of the plug with no definite connection.

[Mickyfinn121]

Originally Posted by Laird Scooby

What gap did you use for the plugs?

Also worth checking, Crank Position Sensor - mine gave these symptoms shortly before failing. Check the RSR (Radio Suppression Relay) and fuel pump relay.

Also double check the terminals on the lead end of the plugs. In the past i've had those come loose on new plugs so the HT leads are just sitting on top of the plug with no definite connection.

It was a gap recomended on this forum by a few people cant remember what that was now haha. Ill give them a check guess its just a case of giving it a once over

[aardvarkash10]

Symptoms: Poor start-up, poor cold running, corrects as temperature increases. No comment on performance under load, so presumably normal.

Rules out fuel pressure, ergo pump, fuel filter etc. Rules out significant ignition HT failure, makes ignition LT unlikely, but not impossible.

Possible faults remaining: cold start fuel enrichment; another odd, or combined set of faults.


First steps: Clean/check the cold start circuit including the temp sensor. Check/clean the AFM.

[Stephen Edwin]

This sounds like an LH engine. First and simplest step read for any fault codes? Or have I missed that having been done?