Hope some one can help ,
We have had this car for 2 years as a winter / lugaround car and it has been reliable untill now. The car will start to missfire ar random ,it feels like the car is cutting out momenteraly rather than one cylinder cutting out. I have fitted a new rotor arm and found the black anti interference cap that fits over the dizzy cap was causing a missfire ,so removed it and the car ran fine. A week later The missfire is back ,so i replaced the dizzy cap ,no difference ,i swaped leads and plugs with a known good set ,still missfireing .
The strange thing is i can watch the injector (single point )pulse extra fuel when it missfires at idle ,but cant see if this is a cause or the result of the missfire .It happens too fast. ???
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This could be a problem with the induction sensor/coil in the distributor. Check the connector and the induction fingers on the rotar plate. Regards Peter
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Thanks ,i'll get a replacement Saturday and see if it helps .
Don't suppose any one knows what the timing should be on this engine ,1.8 single point injection ,1994 ,automatic.
Cheers
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Don't suppose any one knows what the timing should be on this engine 1.8 single point injection 1994 automatic.
There's no timing adjustment as such. As long as all the timing marks are aligned with the engine static, the ECU looks after the dynamic timing
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You should check the wiring and the connector first. When it it is in missing mode is it a regular miss or random. Regards Peter
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It is a random miss ,Yesterday it was quite bad ,but today it missed a few times on the 5 mile journey to work this morning but was fine on the way home .I did blow out the dizzy at work ,don't know if that has made any difference....
The dizzy on this engine is adjustable ,there seems to lots of different engine types fitted to Mk3 Golfs even ones of the same engine sizes
Thanks for your time .
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The dizzy on this engine is adjustable
That's to enable the timing mark on the distributor body to be aligned with the rotor arm centre at TDC with engine static. HTH
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Ok, you obviously know more about Golfs than i do ,I'll save me the bother of breaking out the timing light and finding out the timing setting.
I though the engine was using the dizzy to work out where TDC was ,but from what you say the engine must have a crank position sensor so mayby that could be faulty ?
It could account for the odd popping out of the exhaust ...
Thanks for your time again
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I though the engine was using the dizzy to work out where TDC was but from what you say the engine must have a crank position sensor so mayby that could be faulty ?
No, I'm no expert on the sensors as mine never played up, but suspect it does just use the distributor Hall sensor, in combination with the knock sensors, tacho input, Lambda (and several other sensors) -- AFAIK there isn't a crank angle sensor. If there is a mass airflow meter in the air inlet, that would be another prime suspect though.
Hopefully Peter N or someone else with the knowledge can advise you further. How has it been today?
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Terrible !! I drove it to the scrapyard today where they have plenty of MK3s ,i tried 2 different coils but they didn't have a dizzy that was the same or not damaged.
It didn't run to badly on the way there but on the way home it missfired and poped through the exhaust .It ran worse and worse untill i had to abandon it a mile from home.
I did notice the exhaust was very white ,so it was running very lean .I'll check the fuel pressure at the throttle body when i collect the car later and go from there,Its in the carpark of a care home at the mo !
There is no mass airflow meter and like you say there is no crank position sensor ,i had a look this morning.
It's getting closer to being broken on ebay !!
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check for corroded earth wires on the ECU under the battery. Check the wiring harness that runs across front of engine block across gearbox & under battery tray. there is a connectot 7 it corrodes. check the rubber mounting block for the SPI housing. try lifting it whilst its running.
I Doc
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Thanks for your advise ,i Have checked lots of earths already ,but i'll have alook under the battery to see if i have missed something .
I have also played around with the rubber block on the manifold and squirted water and easy start around it to see if that made a difference ,no luck.
I measured the fuel pressure and it was only 30 psi sounds a bit low to me ? (i fitted a guage to the inlet pipe ,so the engine wasent running )
Thanks for your advise.
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you need to measure inline fuel pressure with engine running, fuel pressure on an SPI is usually between 18 & 30 psi. i would need to check my data on Monday to give you a figure. can't remember of the top of my head, must be an age thing!
I trust you have checked the servo elbow on the inlet manifold, normally melts through underside.
Are you using sechondhand leads & cap etc ? quality of leads & cap etc crucial. Have you gotr a cap with male pins in the cap where the leads plug in ? if so are the right leads fitted to the cap ?
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