spi missfiring
Discussion
having a bloody nitemare with my spi, been trying to find this problem for two years, ive changed everything, but it runs so rich, can you get the ecu reset, or if i covert to carb on a 94 m reg, can i somehow change the engine number, to get it through its next mot, ive spent a sh*t load of money on this car and set to lose a lot more if i cant find this problem, all the sensors have been changed, ive reground all the valves, there doesnt seem to be an air leak, because ive changed all the gaskets.
please help
cheers
please help
cheers
There should be a little pipe that goes to the ECU. I believe these can get clogged and make the car run rich. Might be worth a try if you have not checked it already. You could probably change to carbs but would have to keep a cat as the car must have one if registered after 1st January 2003. Good luck!
I had this problem with my SPI, if it's modified and cold, it will misfire for the first 20 seconds it is less than about 5degrees - there's nothing you can do about this.
However, if it misfires until it fully warms up, it's because the thermostat has been assembled wrong. The thermostat should be in the aluminium housing in the radiator take off - NOT in the cylinder head as on older cars. The head casting still has the groove for the thermostat so it is quite an easy mistake to make.
The reason is that your car is running rich - the ECU takes the temperature from the inlet manifold to adjust the mixture - which it can't do if the thermostat is closed and in the wrong position - so it thinks the car is cold and applies excessive "choke" even though the block is warm but the thermostat hasn't opened yet, so there is no hot water flowing to the inlet manifold and the temperature sensor.
Took me years to find this out too!
Good news is that the fix doesn't cost anything!
>> Edited by tttjm1 on Friday 3rd February 19:59
>> Edited by tttjm1 on Friday 3rd February 19:59
However, if it misfires until it fully warms up, it's because the thermostat has been assembled wrong. The thermostat should be in the aluminium housing in the radiator take off - NOT in the cylinder head as on older cars. The head casting still has the groove for the thermostat so it is quite an easy mistake to make.
The reason is that your car is running rich - the ECU takes the temperature from the inlet manifold to adjust the mixture - which it can't do if the thermostat is closed and in the wrong position - so it thinks the car is cold and applies excessive "choke" even though the block is warm but the thermostat hasn't opened yet, so there is no hot water flowing to the inlet manifold and the temperature sensor.
Took me years to find this out too!
Good news is that the fix doesn't cost anything!
>> Edited by tttjm1 on Friday 3rd February 19:59
>> Edited by tttjm1 on Friday 3rd February 19:59
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