C4 1.6 THP cold weather running issues

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zmax
Posts: 10
Joined: 25 Jun 2020, 07:44

C4 1.6 THP cold weather running issues

Post by zmax »

Hi all,

This morning here the temps were around -3 and I met starting issues in my car. It starts fine but right after that can't hold revs. The engine sound like missfiring but no code for this. I can see that O2 sensors shows data that is not suposed to show, for example upper O2 shows around 1000mV and lower around 800-900mV which leads to mixture problems. HPFP pressure is normal. When I press the pedal and after release it the engine stalls. It's with AL4 gearbox and when select it in DRIVE the engine stalls or work very rough. I wasn't able to move my car from the parking spot more than 3 meters without engine stall after press the accelerator pedal. It was the same situation even when the engine temp reach around 45 degrees.
Any ideas?

PS: just for clarification - this engine is on 7000km after full rebuild, including all sensors
zmax
Posts: 10
Joined: 25 Jun 2020, 07:44

Re: C4 1.6 THP cold weather running issues

Post by zmax »

Some update - today I tried again the car. Problems are the same but this time the fan kicks early together with rich mixture, misfires in all cyllinders and anti pollution faults. The ani pollution is related to the rich mixture which is related to the misfires in my opinion. So I think the cause of my issues is electrical, but the coils are on 2-3k km. Is it possible a bad battery to make such problems?!
zmax
Posts: 10
Joined: 25 Jun 2020, 07:44

Re: C4 1.6 THP cold weather running issues

Post by zmax »

Ok, some update from yesterday.
After work started the car agan. Proms were the same, it was obviously working on 2 cyllinders insted 4 and the fan kicks at the beginning. Wait a little bit to reach 15 degrees and then hold it for few minutes on 2000-2300 rpm until it reaches 40 degrees and final kick the pedal to 5000k. After that just release the accelerator pedal and the car returnt to normal smooth engine run. No issues at all. I saw a LOT of water out of the exhaust...I mean a lot...
This morning I started the car without any problems, no error codes..nothing, it runs just fine.

Any ideas what could have coused this thing?