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Cold Starts

adam 32

By adam 32,
in Engines & Forced Induction

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macka Veteran

macka

Posted
Posted

The ecu is programmed to send fuel to ports on start up without need for touching throttle.

I would think if u need to do this id say ignition timing could be too retarded uumm what does your cars rev at when its cold?

Maybe sticky Idle air control sensor which is on the plenum sorry dont know how to check it tho!

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Guest Boxhead

Guest Boxhead

Posted
Posted

its not neccesarily cold starts that make myn not start.. its at my place.. wont start first try of teh day...

but when i was in sydney, i noticed where i parked the car.. it was downhill.. not slightly up hill.. so maybe that has somethin to do with it...

in sydney, on even freezing cold days, would start straight away

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002 NVS Proficient

002 NVS

Posted
Posted

I dont know about skylines because I havent got the same problem with mine, but in my old GTi corolla I had problems with starting it codl or hot, I would have to pump the accelerator to get it to fire..

After I gave it a service and a *new set of plugs* it started beutifully..

Give it a go..pull your plugs and see what they look like, check the gap. If they're no good replace them and see what happens..

If it still doesnt work then u may as well give your car to me....:D

hope it helps..

Scott

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Bozz Proficient

Bozz

Posted
Posted

The ignition barrel has two wires coming from it when you turn the key to the "start" position. One wire goes the starter motor, the other wire goes to pin 43 of your engine control unit.

When you turn the key to the start position, the ECU senses that you are attempting to start the engine by using the starter motor, not attempting to roll start the engine. Since using the starter motor demands a bit over 100 amps of current, your battery voltage falls quite dramatically. To compensate for this, the ECU makes the injector pulses much wider to get the fuel into the motor. It may not do this if you have your foot on the accelerator so it could even be the throttle position sensor faulty or misadjusted.

If you had an alarm installed when the problem started occuring, take it back to the butchers... oops I mean installers who fitted your alarm and have them correct it.

Cheers

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  • 4 months later...
macka Veteran

macka

Posted
Posted
Originally posted by macka

you run 11;1 with the to4 Adam?

14psi im getting 13:1 bad news 4 me

Cant even remember saying that :P

13:1 full load is pretty lean

Most guys agree with anything under 12:1 safe

After i fit my fuel pump in it brought it back down to 10.2:1 and then tuned to 11.6:1 roughly

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red17 Experienced

red17

Posted
Posted

My 32 GTSt also starts badly when cold. Can usually get it to go first try now, but sometimes 2. Ive just got mine back from having 2 exhaust valves done so its got all new plugs in it, theres NO internal issues with the motor. Still starts badly

Ive been told this is a common thing with cars that have had remapped ECU's or aftermarket ones. Many have cold start features removed. Mine is a Blitz Access ECU.

After doing 2 exhaust valves in cylinder 6 and ingesting an electrode, my advice to anyone out there wanting to run 1 bar with a stock intercooler is, DONT.

Red17

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macka Veteran

macka

Posted
Posted
Originally posted by red17

My 32 GTSt also starts badly when cold. Can usually get it to go first try now, but sometimes 2. Ive just got mine back from having 2 exhaust valves done so its got all new plugs in it, theres NO internal issues with the motor. Still starts badly

Ive been told this is a common thing with cars that have had remapped ECU's or aftermarket ones. Many have cold start features removed. Mine is a Blitz Access ECU.  

After doing 2 exhaust valves in cylinder 6 and ingesting an electrode, my advice to anyone out there wanting to run 1 bar with a stock intercooler is, DONT.

Red17

You dont think that it would of still happened if u were running lower boost or a FMIC?

Well at least your back on the road..

I would hope tuners like Blitz wouldnt remove the cold start function on your ecu because its not to anyones advantage..but i guess its possible.

I have found when my timing is retarded slightly i have this problem, I assume its been checked but if you run abit more....18 degrees it may fix it..

just a thought

cheers

mac

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Cubes Grand Master

Cubes

Posted
Posted

Mine splutters every now and again on cold starts.

I tried turning the ignition to the on position for a couple of seconds and then starting but it did the same.

Slight splutter then up come the rev's.

Also on the note of AF's.

When i had mine on the dyno with the new fuel pump on 15psi she was down at around 10.5:1.

Is that normal for a 32 with a stock turbo?

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