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bdearnley
30th November 2000, 09:18
Most of the problems with hot starts that have previously been discussed on this forum are ecu (particularly Link) related, but I have a hot start problem that is not ecu related, and I don't know what else to check.
I know it's not an ecu problem (I have an Australian one called a Microtech), because I never had a problem with hot starts for a year after the ecu was installed and tuned. Now the problem had suddenly appeared, and i can't find the cause. So far we have checked or replaced:

Fuel pressure
injectors (leaking etc)
spark
crank angle sensor
cam angle sensor
compression
all ecu settings

What else is there? I know it will turn out to be something stupid and small, like one bad earth or sensor connection, but so far we can't find it. Once the engine does start it stumbles and coughes with a slow idle which takes about five seconds to stabilise and then idles smoothly. The car drives brilliantly - it's just the bloody starts, which were fine a week ago, and I have changed nothing!!

Help!

GavinP
30th November 2000, 10:58
Have you changed the coolant temp sensor (if the Microtech uses it) ?

Thanks

Gavin

Victor L
21st December 2000, 17:35
Does this come up as a code 11 - Crank Position Sensor?

I had this problem and got the sensor changed and it's fine now.

Victor.

bdearnley
23rd December 2000, 22:49
No, but thanks for your input. The problem is now solved, and turned out to be my dodgy aftermarket ecu. For some reason it was referring to the 'limp home' settings for cranking, and because they hadn't been set by my tuner, they were set really rich from the factory - so rich, in fact, that the car wouldn't start. The ecu normally only goes into limp home when it senses a problem with the signal from the TPS, but it is recording no error messages to that effect. Once the car is started, it refers to the normal maps, so I can't figure it out. To solve the problem temporarily, I've just set all the 'limp home' values (which just refer to engine speed) to zero, so now it looks at the normal maps for starting values and crank enrichment etc.