R33 Skyline Start Up Problems In The Morning

[Deza3000]

so is this the definitive cause? would it also be leaks as suggested?

Im gonna give both the aac valve and the cold start control valve a good clean tomorrow, ill report back if i find any changes but so far from what i have researched, it seems to be the cure for the cold start up problems every morning. Im gonna clean the o2 sensors as well. Hopefully it makes a difference.

[tripsteady]

Im gonna give both the aac valve and the cold start control valve a good clean tomorrow, ill report back if i find any changes but so far from what i have researched, it seems to be the cure for the cold start up problems every morning. Im gonna clean the o2 sensors as well. Hopefully it makes a difference.

cheers awaiting your post

[dyl33]

I don't reckon AAC valve is the culprit. My idle is fine it's just the first 3-5 seconds in the morning thats hecktik. But I'm going to clean the AAC valve anyway tonight so we will see.

[tripsteady]

Hmmm...every morning same thing with me....Idles low when I first start , sputters and sometimes dies....If I blip the throttle slightly it seems to "catch" and hold its revs. I plan to put a remote start in soon so this is quite annoying. Lets hope we find the culprit quickly and if we do...then lets get this as a sticky...

[dyl33]

Well I cleaned the aac valve. It felt better for sure but it still died, I havn't driven the car for a couple of days so it was prob going to start shit anyway, So will see tomorrow for sure if it worked or not.

[Deza3000]

Well I cleaned the aac valve. It felt better for sure but it still died, I havn't driven the car for a couple of days so it was prob going to start shit anyway, So will see tomorrow for sure if it worked or not.

Cheers for the report dyl33, ive been a little busy past few days, ill clean the aac valve out tonight and report back if i see any difference. But still its good to see that it made a bit of difference. I started my car this morning and it didnt die this time, I left it outside in the cold over night for the first time in a few months instead of in the garage, it didnt struggle as much to start which is odd, but maybe that's just a one off coincidence. Edited July 27, 2012 by Deza3000

[Deza3000]

Ive just finished cleaning the aac valve and it starts up so much better, just went for a long drive. The start up was almost instant, very smooth and quieter idle than before, however thats only in the period of 5 hours since it was last turned on. I will let you guys know how it starts tomorrow morning, hoping for the best, but other than that so far so good!

[tripsteady]

well its just gotten worse for me. was extremely cold this morning , started it up , revs started to drop , so i blipped the throttle slightly , when i took my foot of it started to drop again. this is the first time its happened. I had to rev it a bit higher for it to "catch" and hold steady...

Will be looking at my aac and following this thread closely

Edited July 27, 2012 by tripsteady

[Deza3000]

Hey guys, its been 2 days since i last started the car, started the car up this morning, and i gotta say, it started up absolutely brilliant. The revs started off low for not even a millisecond and it was pretty much 100%. No lumpyness, no idle problems, no stalling. Cleaning the aac valve pretty much worked for me. i give it 9/10 points. Just a heads up i didnt just clean the aac valve, but i cleaned the intake where the aac valve connects too, as well as the pipings and all surrounding areas, spent 3 hours cleaning it. Used a tooth brush to scrub off all the dirt etcc. Hopefully it works for you guys too, i also turned the idle control valve fully open to clean out the gunk, then i returned it to its original postion, i also used a vaccum cleaner and sucked any stray dust that was present in the intake and in the aac valve. Other than that, i pretty much followed the rest of the diy guide.

[tripsteady]

Hey guys, its been 2 days since i last started the car, started the car up this morning, and i gotta say, it started up absolutely brilliant. The revs started off low for not even a millisecond and it was pretty much 100%. No lumpyness, no idle problems, no stalling. Cleaning the aac valve pretty much worked for me. i give it 9/10 points. Just a heads up i didnt just clean the aac valve, but i cleaned the intake where the aac valve connects too, as well as the pipings and all surrounding areas, spent 3 hours cleaning it. Used a tooth brush to scrub off all the dirt etcc. Hopefully it works for you guys too, i also turned the idle control valve fully open to clean out the gunk, then i returned it to its original postion, i also used a vaccum cleaner and sucked any stray dust that was present in the intake and in the aac valve. Other than that, i pretty much followed the rest of the diy guide.

cheers for that , will definitely give this a go and post results

[dyl33]

Hmmm, Why didn't it work for me? Was I suppose to clean inside the aac solenoid (the brown plug)?

[Deza3000]

Hmmm, Why didn't it work for me? Was I suppose to clean inside the aac solenoid (the brown plug)?

Yea you were actually, also try turning the throttle a little, open it up a bit more

[dyl33]

lol You reckon I could clean the aac solenoid with the aac assembly still on car, just un-screw the solenoid?

Edited August 1, 2012 by dyl33

[Deza3000]

Yea you could, its a real bitch to unscrew though, took me ages and i nearly stripped the screws =[

[dyl33]

Yeah I did it, Still no good. Don't think aac valve is the problem, If I press the throttle prior to starting it, It cleans it up a lot, Could it be a injector, fuel pressure problem or somthing like that? I have nfi

[Deza3000]

It must be the cold start valve under the plenum, from what ive seen around the skyline forums a lot of people are having this problem, how ever there still hasn't been 100% guaranteed solution to why it has been happening. No one really had bothered to clean the cold start valve under the plenum. A few people with turbo'd skyilnes cold start problems were due to aftermarket bovs etc...I dont think it would be a fuel injector problem cause then you would start to see symptoms while driving as well. And yes that was the same case with me too, when i tickled the throttle the motor would stabilize , thats why i opened up my aac valves idle position all the way so it does a slight throttle when starting up, eliminating the problem. However this is at the cost of ruining my idle position, now it idles at 950 rpm as opposed to 700. Ill have to give the cold start valve a shot by cleaning that, ill have to get done by the mechanic.

[Deza3000]

Just an update, ive done a little experiment, i returned the throttle to its original position on the aac valve and turned on the car, but this time what i did was i turned the key for a fraction of a second longer than usual, and the car started up perfectly. Basically just hold the key in the ignition position for 0.5 to 1 second longer and it should start up normal. My theory is, the spark isnt fully igniting the fuel because the battery dies over night explaining why it happens every morning, resulting in the car to struggle on what little spark it was given to start up the motor. This is just my theory, but you guys should give it a shot, turn it on for a fraction of a second longer. Hope it works!

[tripsteady]

Just an update, ive done a little experiment, i returned the throttle to its original position on the aac valve and turned on the car, but this time what i did was i turned the key for a fraction of a second longer than usual, and the car started up perfectly. Basically just hold the key in the ignition position for 0.5 to 1 second longer and it should start up normal. My theory is, the spark isnt fully igniting the fuel because the battery dies over night explaining why it happens every morning, resulting in the car to struggle on what little spark it was given to start up the motor. This is just my theory, but you guys should give it a shot, turn it on for a fraction of a second longer. Hope it works!

worth a try for you guys but ive put an optima yellow top in recently and there is no way the battery has anything to do with this problem

mentioned it to Paden when I dropped my car off for the 100 thou service this morning , lets see what he comes up with.

[dyl33]

Today I held the key in the start position for 1 second longer , And it fired up perfect... What the hell

[Deza3000]

Today I held the key in the start position for 1 second longer , And it fired up perfect... What the hell

So it worked for you too aye? Well i guess its good news we found the cure, but i dont understand why it needs that extra second. Atleast i wont have the dodgy start ups anymore. And i guess that aac valve didnt really do much in the end. Only way the aac valve would help the start up problem was if you increased the idle speed, which was getting rather annoying, hence why i returned it back to normal and done this little experiment ;p. Glad it worked your you as well!