Hesitation When Cold

[agentx]

hey guys, im certain this has been covered before. Maybe im using the wrong key words

the symptoms are: when i start the car cold ... it hesitates around 2000 - 2400 rpm for a couple of seconds before taking off ... i just wanna know what the possible causes are? Skylines have cold start valves as well im guessing? Could that be it? It's fine once it warms up and all.

What could be the possible causes? Any links to other threads would be fine as well

Cheers

[trel]

Start off by cleaning your aac valve, diy tut is on here, look it up and do it! changed your plugs lately? if not do it! check your coilpacks while your at it. Once again there is a diy tut on here for that too. Chances are its your plugs that are worn and during cold start the car runs very rich and could possibly be not burning the fuel properly in the cylinder causing a miss/hesitation. I had a similar issue in my car where I would start it and it would idle shit for a few sec then come good. After a new set of plugs the car starts like brand new again. Good luck.

Cheers.

[agentx]

thanks mate, i'll try and find the tutorials. and yes i haven't serviced the car since i bought it 2 months ago or something ... i'll do it asap, as soon as this shit weather turns good lol.

Cheers

[trel]

I hear ya bro. Good luck with it man, if you need a hand let us know.

Here are the tut's you need anyway:

http://www.skylinesaustralia.com/forums/Di...html&hl=aac

http://www.skylinesaustralia.com/forums/Fi...html&hl=aac

http://www.skylinesaustralia.com/forums/RB...ml&hl=plugs

Cheers.

[paulr33]

it will be the cold correction in the ECU

the ECU has correction based on water temp - the colder it is, the more retard the timing is and the more rich it will be

until it reaches 80deg water temp - it has linear scarling of correction upto 80deg temp. as the water temp rises, the linear pans out

ie: 0 to 15deg will be more aggrssive than 50deg to 80deg as an example

[trel]

Coolant temp sensor play any role in that? I wouldn't think on a dead cold start it would?

[agentx]

thanks for the links mate, changing spark plugs looks lengthy lol. took 4 mins to do on my swift gti hahah. as for the AAC, I understood the majority of it, but just the adjusting idle part seems lengthy, i HAVE to take out the ECU to adjust idle? i mean its fine where it is right now, dont have a problem with the idling. Also, TPS adjustment isnt necessary yea?

thanks again!

[trel]

Yeah not necessary. As far as idle adjustment on ecu is concerned chances are you probably wont have to do it. Stuff around with the screw on the aac after its all back together and then if you are having idle issues look at the ecu screw. Not hard man, just take off kick panel on passengers side and ecu is right there.