M
mick price
Guest
Hi All
I found this site by searching for help on these problems, and it seems to be quite a common theme. I have just spent two days of my valuable holiday with my head under the bonnet of my daughter's car, and I have got to the point where I could do with a bit of advice.
The car is a 1.0 1993 "L" reg, The problem is this: Always starts OK from cold, and runs absolutely fine. If she stops, eg for petrol, with a warm engine and then tries to restart it is difficult to start. Once it does get going it misfires quite badly until you rev it like mad a few times, then it seems to settle down. When it misfires, there is a definite "pop, pop" sound coming from the exhaust, so it sounds as if the ignition is firing with one or more exhaust valves open. I initially suspected a sticky valve, but why should it only stick after the engine has been switched off?
From reading the threads on here, it sounds like a replacement throttle body may be called for, as that seems to be the main cause of all poor running and starting problems, but does anyone have any other ideas before I commit to the spend.
Two points that I have noted that I would welcome comment on:
i) The cooling fan runs as soon as the engine starts, even when cold. Is this correct. I have checked the resistance of the temperature sender unit and it is correct according to Haynes. I'm wondering whether the ECU is programmed to turn on the fan if the engine is running but the car is stationary. Is anyone able to confirm this?
ii) The voltage across the Airflow meter in the throttle body is 1.2V at idle. Haynes says it should be approx 2.0V Does anyone know if this is a large enough discrepancy to be causing the problem? Is Haynes correct anyway? It wouldn't be the first time they have been wrong!
By the way, I have replaced distributor cap, rotor arm, plug leads, plugs, air filter, fuel filter, oil and oil filter.
Thanks a bundle for reading this, and for any offers of advice.
Best regards and Happy New Year
Mick
I found this site by searching for help on these problems, and it seems to be quite a common theme. I have just spent two days of my valuable holiday with my head under the bonnet of my daughter's car, and I have got to the point where I could do with a bit of advice.
The car is a 1.0 1993 "L" reg, The problem is this: Always starts OK from cold, and runs absolutely fine. If she stops, eg for petrol, with a warm engine and then tries to restart it is difficult to start. Once it does get going it misfires quite badly until you rev it like mad a few times, then it seems to settle down. When it misfires, there is a definite "pop, pop" sound coming from the exhaust, so it sounds as if the ignition is firing with one or more exhaust valves open. I initially suspected a sticky valve, but why should it only stick after the engine has been switched off?
From reading the threads on here, it sounds like a replacement throttle body may be called for, as that seems to be the main cause of all poor running and starting problems, but does anyone have any other ideas before I commit to the spend.
Two points that I have noted that I would welcome comment on:
i) The cooling fan runs as soon as the engine starts, even when cold. Is this correct. I have checked the resistance of the temperature sender unit and it is correct according to Haynes. I'm wondering whether the ECU is programmed to turn on the fan if the engine is running but the car is stationary. Is anyone able to confirm this?
ii) The voltage across the Airflow meter in the throttle body is 1.2V at idle. Haynes says it should be approx 2.0V Does anyone know if this is a large enough discrepancy to be causing the problem? Is Haynes correct anyway? It wouldn't be the first time they have been wrong!
By the way, I have replaced distributor cap, rotor arm, plug leads, plugs, air filter, fuel filter, oil and oil filter.
Thanks a bundle for reading this, and for any offers of advice.
Best regards and Happy New Year
Mick
