M40 316i/318i sputtering when warm temperature gauge 1/4

[201964]

I have a 1991 316i that sputters after the engine is restarted when warm. Sometime it losses all power and you have to floor it to get it to go. Also the temperature gauge never reads much more than below the 1/4 mark just out of the blue!
So overall it'll be ok from cold and driving a lot of miles like 100, then if you stop the car it'll just splutter from after you start her. I initially thought it was the fuel filter as the car had been sitting when I bought her, but after two new filters it does the same thing. Same every time, engine warm, you've stopped the car and started again starts to splutter. I see it on other forums but no one has found a solution, hopefully someone here will help.

[Brianmoooore]

Get yourself a cheap fuel pressure test kit off of ebay, like this: http://www.ebay.co.uk/itm/Universal-Fue ... SwAuZX17QD , or similar, connect it up, and see what happens in the minutes after you stop the engine.

[201964]

Brian what should I expect to see from the fuel pressure test kit?

[Brianmoooore]

On a good car you should expect the gauge to read the pressure written on the side of the fuel pressure regulator after you stop the engine, and it should remain there, without dropping much, for days.
If yours doesn't, then we're on the track of the problem.

[201964]

Brian stop teasing

[201964]

Anyway got a 20pin to 16pin OBD convertor cable and ran the diagnosis on the car, came up as fault code 7 MAF/AFM. Great as the fix looks simple just clean the contacts on the potentiometer.

[soul4t]

I know it's a bit late, but if the temp isn't getting above 1/4 of the way, I believe you may also need to replace the thermostat as it may be stuck open.

[201964]

I know it's a bit late, but if the temp isn't getting above 1/4 of the way, I believe you may also need to replace the thermostat as it may be stuck open.

I replaced the thermostat, now runs at close to 1/2. Thanks

[soul4t]

Ah great : )