306 diesel idle problem after start-up - Dan G
I have noticed a new characteristic develop on my 98R 306D, and could do with some help in finding the problem. It has only started recently (since a service by myself), and only seems to occur if you start the car between half an hour and 2 hours of turning the car off, only if the car was hot (over 80 degrees C) - A typical example of this temperature would be stopping at a motorway service station. The car starts and idles at the correct speed for 2 seconds, then the idle climbs to between 1500 and 2000 for a few seconds and then returns to normal. It doesn?t happen when it?s cold, or when it?s warm ? only hot. Any ideas ?

Initially after the service, the car would cold start normally, idle for 1 second and then stall. It would then start immediately afterwards. I thought this could be air in the system, so re-fitted the fuel filter and bled the system, and this problem hasn?t occurred since (just thought I?d include this in case it?s related).
306 diesel idle problem after start-up - mph_turbo
I've had a similar ongoing problem with my 306 except my car would rev to 2000rpm after a hot start and then stall. Mine was way worse in very warm weather!! It would take perhaps 20 secs to restart and everything would be fine then.

One thing I found was that the fuel pump was full of air when one of these stalls would occur. So I checked the bleeder bulb for holes and also replaced the fuel filter bowl as I thought that heat was causing some air to get into the fuel system.

This seems to have partially fixed the problem. My car still revs occasionally after a hot start but considering it has 140k and has had a hard life with me, I just accept this as yet another one of its peculiar characteristics!!

MPH
306 diesel idle problem after start-up - Dan G
Interesting. It seems strange that it only started happening after a fuel filter change, so you could be right. Did you only chage the fuel filter housing ?

I wondered about the idle control mechanism which sits behind the fuel filter housing and screws into the cooling system. It monitors the engine temp. and adjusts the idle accordingly.
306 diesel idle problem after start-up - mph_turbo

I just changed the filter bowl. I didnt go near the idle control mechanism.

MPH
 

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