Cold Start In The Morning... Car Wont Rev Past 1k

[r33madd]

Hmmm iv had my car 3 years and never had this before.

On very cold/frosty mornings my car wont rev past 1k......seems to be some type of fail safe

Then by the time I finish work at 5 its all up and running fine again. and on a worm morning it also works fine.

One thing I noticed is when it wont rev my SAFC shows no rev reading.. does this mean anything ??

I have checked for boost leeks etc. and just did a full fluid and filter service on the weekend.. and still getting the same issue on cold mornings.

any idea would be awesome

Thanks

[Adriano]

Have you done a trouble code check?

[r33madd]

Yep sure have and it shows up normal.

in the cold and worm

[PM-R33]

Check your water temp sensor. Does your dash water temp work fine?

You havn't accidentaly changed one of the sensor settings on the SAFC? I can't remember what they are on the SAFC but i remember there being a few settings regarding the inital setup.

Edited August 27, 2008 by PM-R33

[r33madd]

yep water temp is all working sweet as..

its running standard ECU with piggy back SAFC-II

I disconnected the SAFC and ran only factory ecu and i still got the prob on a frosty morning

[PM-R33]

How cold of a morning are we talking about? Like temperature wise?

[r33madd]

hmmm 4deg to -3deg approx

[PM-R33]

Hmm interesting. When you say it wont rev past 1000rpm, as in it wont even rev past it in neutral or only when your in 1st gear trying to drive? Also when you try to rev past 1000rpm does it sound like a rev limiter bouncing off of 1000rpm or something else?

The only thing i can think of is the temperature of the coolant being that low that it is going into some sort of factory safety on the stock ecu and wont allow the car to go until it warms up a bit.....probably not that but just thinking out loud.

[r33madd]

yea also thought the same. it does in neutral and in gear. it bounces off 1000rpm like the is a boost look e.g a slow bob up and down.

i have left it to sit to get to running temp and still no luck.

only thing that get it going sweet is leave it for the day and try after work haha then all is go..

[PM-R33]

Wow that is very weird indeed, never heard of anything like it

[r33madd]

Thanks anyway mate...

Anyone else got any ideas.

[SeanR33]

Hey mate,

Yeh ive got the same problem, only in the mornings, mine wont rev past 2k.

Ive got someone looking at it today, so hopefully ill have a answer for you soon.

if anyone else has had this problem let us know.

[r33madd]

Cheers mate thanks for the heads up.

look forward to your reply

[SeanR33]

Yeh mate,some auto electric guy pluged it all in, come up with no problems at all, He said he couldnt find a thing wrong.

He has never heard of anything like this before.

Someone Help!

[Julz89]

could it be some sort of knock sensor, because on cold mornings engines are more common to knock, think of it as a good thing i guess at least you wont get any engine damage i guess.

[Al]

But it doesn't lift the rpm once the car is warm, so it is not a factory safety feature.

I assume after you left it to warm up and it still wouldn't rev past 1krpm, you turned it off and on again; and it still would rev past 1krpm.

I am more inclined to think "dry joints" in the AFM

or

Even cracks in the coil packs and the moisture in the air is causing a short to the engine.

Ask a fellow Skyline mate to swap parts for a short period of time.

ie: Swap AFM, see if fault reoccurs, then try coils, then ignitor pack, etc.

ONLY swap one item at a time, and swap back before testing another item.

If that's not possible then try using a heat gun or hair dryer, the next time the problem occurs. Once again only try gently heating one component at a time.

[SeanR33]

Hi,

Thanks for the tips, I have left the car running for like 30mins and it still does it after that,

I dont no if moisture is the problem. But ill give it a go and get back to you.

[r33madd]

thanks for the reply guys. hmm still not much luck.

have also tried the above with no luck at all. have also tried re-setting the computer and no luck there either.

I have Splitfire coils like 6 months old so dont think its them haha well bloody hope not any way.

It may very well be AFM so this week ill try another one and/or clean it with AFM cleaner. will aso give all connections a clean up with crc.

again will let ya know.

[bubba]

But it doesn't lift the rpm once the car is warm, so it is not a factory safety feature.

I assume after you left it to warm up and it still wouldn't rev past 1krpm, you turned it off and on again; and it still would rev past 1krpm.

I am more inclined to think "dry joints" in the AFM

or

Even cracks in the coil packs and the moisture in the air is causing a short to the engine.

Ask a fellow Skyline mate to swap parts for a short period of time.

ie: Swap AFM, see if fault reoccurs, then try coils, then ignitor pack, etc.

ONLY swap one item at a time, and swap back before testing another item.

If that's not possible then try using a heat gun or hair dryer, the next time the problem occurs. Once again only try gently heating one component at a time.

Agreed, doesn't sound like coldstart or limp mode.

On a coldstart note, now that I have Datascan running all the time, I have discovered that the ECU comes out of coldstart once water temp hits 65deg

[sxwpn]

yep i got the same problem when i start the car in the morning it will not go past 1k and will eventually stall but if i giv it some gas its fine i got it dynoed today and 2 problems came up error in the ECU and AFM does your car idle rough when its warm like shake the inside of the car????????