1.4 petrol twist, engine cut out when cold

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flub136
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Joined: Thu Oct 24, 2019 1:42 pm
Drives: 1.4 petrol 9N
Location: Jersey

1.4 petrol twist, engine cut out when cold

Post by flub136 » Tue Dec 03, 2019 2:18 pm

Hi All. Hoping someone can shed some light here. I have the above vehicle (BKY engine) that is causing a nightmare when driving now. Basically when driving from cold the car will pull away and then go into a complete frantic intermittent full engine cut out and then come to life again. It's like the car just kangaroos up the road with the rev gauge bouncing all over the place. If you come to a junction it may just stall completely. Sometimes it will start immediately after this, sometimes it will have to be turned over and revved hard to get it going again. When it's warm (does not take more than a few minutes to get fully warm (90 degrees)) it behaves its self. I have started to counter this by starting in the morning 10 minutes before leaving for work and letting it idle on the drive. Usually it starts first go, even when cold, and then I just leave it to idle and get warm. Usually that is sufficient to stop the problem although sometimes I come out of the house to go and find the car has stalled on the drive after a few minutes and the battery light and sometimes the coolant level/temp light is flashing and beeping at me. obviously I have checked the level and it is correct with no leaks and the temperature is in the normal range. My friend is a mechanic and plugged in his £2.5K snap-on ODB reader/analyser and it is not reporting any codes at all. At the beginning of the summer I replaced the crank sensor to cure a misfire problem that was not to dissimilar to this but no where near as violent in the full engine cut out I get now. I also replaced all the plugs and the temp sensor at that time. I have also given the throttle body a complete clean with carb cleaner (body off the inlet manifold) and reset by disconnecting the battery for 20 minutes. Anyone with some wise suggestions? All gratefully received.

littlepolo
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Re: 1.4 petrol twist, engine cut out when cold

Post by littlepolo » Tue Dec 03, 2019 2:47 pm

If you removed the throttle body to clean it you need to do a calibration on refit.

flub136
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Joined: Thu Oct 24, 2019 1:42 pm
Drives: 1.4 petrol 9N
Location: Jersey

Re: 1.4 petrol twist, engine cut out when cold

Post by flub136 » Tue Dec 03, 2019 10:13 pm

That I could get my mate to do but the problem still exists same as before I cleaned the throttle body. The car still fast idles fine (runs rich like the choke is on) when starting cold but the revs drop to normal idle (680 rpm approx) within a few minutes if starting so it seems the ecu is fuelling the engine properly when cold starting. Was wondering if it may be something electrical as it is a total engine stall rather than errant cylunder misfire.

littlepolo
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Re: 1.4 petrol twist, engine cut out when cold

Post by littlepolo » Wed Dec 04, 2019 8:45 am

You mentioned above it takes only a few minutes to get warm to 90C which sounds very quick to me (at this time of year).

It might be worthwhile plugging in a diagnostics and monitoring the temp sensor as it warms from cold. If the signal is reading over and fueling is reduced that could explain the stall.

flub136
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Drives: 1.4 petrol 9N
Location: Jersey

Re: 1.4 petrol twist, engine cut out when cold

Post by flub136 » Wed Dec 04, 2019 6:10 pm

Littlepolo, thanks for the reply. We did plug the reader in when the car had been left until cold and the temp sensor read 12 degrees whixh was the approx ambient temperature at the time. We didn't however monitor it after i started the car. I was thinking about changing the sensor again just in case the new one has gone faulty.

littlepolo
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Posts: 509
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Re: 1.4 petrol twist, engine cut out when cold

Post by littlepolo » Thu Dec 05, 2019 9:40 am

I think they usually go faulty the other way (as in reading cold leading to enrichment) but it's worth ruling out.

It does sound like you are possibly leaning the mixture leading to stalling?

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