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missing on cold nights ?

DJ_L3ThAL

By DJ_L3ThAL,
in Engines & Forced Induction

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DJ_L3ThAL Grand Master

DJ_L3ThAL

Posted
Posted

ok i had the misfiring problema nd it was fixed with regapping sparkies to 0.8mm... but now its missing still but only when the ambient temperature is really low (ie. at night.. like tonight) ios this still the sparkies or coiul packs or just i have to accept i cannot go hard on real cold nights ? i thought the colder the better ? hmm

im getting a powerfc etc done soon will they have tp check all of this out anywyas ? coz im going back to stock boost etc tomorrow until i get he pwoerfc shoujld i just wait until then and get everything setup perfect ?

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SLY33 Mentor

SLY33

Posted
Posted

i had that problem, thought it was a miss. What was happening was that on colder nights the boost creeps just enough higher to hit the factory boost cut, and id get a couple of pops while revving it out. as soon as the day got warmer it disappeard. On cold nights i just turned to boost down a touch and it was fine. Now i have PFC and no longer a prob.

what boost are you running? this is probably your problem.

PS- DJ, your car looks f'in sick! what bar you got on the front? cant really see from the pic. And what are those wheels?

DJ_L3ThAL Grand Master

DJ_L3ThAL

Posted
  • Author
Posted

ONLY RUNNING 10PSI lol

uh the wheels are some jap ones with carbon fibre coating :D and the front bar is a 'modded' standard mspec one with a huge mouth for my huge cooler lol as in the attachment

*sigh* i guess ill just wait until i get a powerfc :) should only be acouple weeks max

Cool Hand Luke Community Regular

Cool Hand Luke

Posted
Posted

Its typical for an engine to run leaner on cold nights, as the air is denser. But one great thing with modern ecu's, they have temp sensors which are supposed to adjust the fuel accordingly. This probably doesnt relate to you car but i remember reading in zoom that anything like an intercooler could upset the AFM.

JimX Grand Master

JimX

Posted
Posted

The main reason why our old carbie-fed cars did not run well in cold weather even with the choke on is because there is not enough energy in the spark to ignite the fuel mixture.

This can be directly because the ignition coil wasn't up to the task, or more commonly, because the carbie is not atomising the fuel enough. ie, cold fuel clumped together is much harder to burn than a fine mist of warm fuel. So you could fix it by either cleaning or re-jetting your carbie for better atomisation, or getting yourself a higher energy ignition system.

Try cleaning your injectors and checking your spark voltage. I'm not sure how you'd do the latter, so start with some injector cleaner in the tank and see what happens.

Also maybe check your TPS, it could be a mixture issue.

DJ_L3ThAL Grand Master

DJ_L3ThAL

Posted
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Posted
Originally posted by SLY33

looks neat, do you ever get done for no front number plate?

not yet.. only been off for about a week.. i ordered a really small one to be mount4ed to the side and i cbf putting the large one on temporarily :) ill just say its stolen :D

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