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Discussion Starter #1
Hi
Recently, I had to replace the cylinder head gasket after a drift day at santa pod, as the head had lifted slightly. After replacing the gasket, when I started it I found that the idle control valve was stuck open, causing the "idle" revs to be at about 3000+. So I have replaced this, and the new one i have works fine. But now, there seems to be another problem. Sometimes the car turns over but doesn't start, even if i open the throttle slightly, other times it starts just fine. when it first starts, the idle settles to a normal level, like 7-800 rpm, but when you rev the engine, the response is terrible, it often splutters, and when you let off the throttle, the rpms drop down massively, to 3-400 rpm, and the car almost stalls. it takes a while to settle back to a normal idle speed, and the rpm fluctuates while doing so. To me, it seems as if the AFR is changing massively, between rich and lean when i open the throttle. But I don't know. Has anyone else had any similar issues? and how do you resolve them? do you have to get the ECU "reset" after doing something like this?
Thanks IMG_20190131_161258794.jpg
 

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Any air leaks?
Sounds like the engine is sucking in unmetered air.
 
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Discussion Starter #3
Thanks, but that wasn't the issue after all; it was the lambda sensor, and now that is sorted.
However, When the car has been running for a short time, the engine coolant temperature now increases very fast into the red, like the car is overheating. But the top radiator hose is only slightly warm, the lower hose is still cold, and the valve cover is stone cold.
I'm guessing that its the coolant temperature sensor that's gone wrong, but I can't find a definite answer anywhere.
Any ideas?
 

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For the sake of the price of a coolant sensor,id replace it anyway.
 

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Discussion Starter #5
Haha yeah, I replaced the sensor, but the problem remained
It was only then that I worked out that the wire for the DME and the wire for the coolant temp gauge were in the wrong way round. After swapping them around, everything worked perfectly; the car slowly got up to temperature when left to idle, and stayed there. After changing the oil and coolant (and spending 2-3 hours bleeding the coolant system) the car worked perfectly at the next santa pod DWYB event.
Now I can just focus on drifting and not blowing up the engine lol
 
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