Just rebuilt my NA8 - Strugles to start cold and idle is high/funny - see videos

[booki89]

Hey all,

Recently just rebuilt my engine (new bearings, NB pistons, reco head), and so far so good, its running very clean and sounds great...bar these issues.

When I start the car cold, it cranks for a while, then will eventually fire up. I have a video to better describe this. The car has new spark plugs, leads are not that old, and internally its all new, after cold start it seems to startup just fine !

The next thing I have noticed, is the car stays idling at 1500rpm for quite a while, I understand its probably normal for it to stay at 1500rpm when its cold for a little bit and then drop down to about 850ish, mine seems to stay at 1500rpm for quite a while, and seems to hover around it when i have accelerated and stopped. I am yet to take the car for a actual drive, so not sure if its just the ECU in some kind of "learning" mode because the battery has been off for quite a while.

Check out the videos and tell me what you think!

Cold Start: https://youtu.be/dVMnZ3vXrAc

After Cold Start: https://youtu.be/wqN64MGPmto

I am thinking it is fuel related.


Setting my timing -

Now my understand to set the timing, is to have the TEN and GND terminals bridged together, which will make the engines rpm drop to about 850-900rpm, mine does not do this. It did for like a second, then just went up to 1500rpm and stayed there. I cannot accurately set the timing with the motor revving at 1500rpm, has anybody has issues like this before? I cleaned the throttlebody and plenum out while it was all apart,

https://youtu.be/qi8BlmUe9j4

My idle screw is turned all the way in, its how its always been, there is slack on my throttle cable, i am really unsure where to go from here.

[93_Clubman]

My idle screw is turned all the way in, its how its always been...

Appreciate that's how it's always been during your ownership, but it shouldn't be fully screwed in - back it off 1.5 turns to start with. Manga_Blue has suggested backing them off 2.5 turns, so it will vary. Mine ended up at just under 1 turn for correct idle speed, but have read that correct idle speed is usually found between 1 & 1.5 turns.
See Manga's posts here:
viewtopic.php?f=29&t=62492&p=783221
viewtopic.php?f=29&t=34906

[booki89]

Figured it shouldn't be...I'll put it out a few turns , ID imagine the previous owner masked the actual issue. None the less it's going to be tough trouble shooting these niggling issues.

[project.r.racing]

IAC valve is sticky for prolonged high revs and after accelleration.

cold start - unsure. not enough info provided. could be an array of things. especially if fuel system has sat around unused for sometime while rebuild was done. i could guess air in the fuel system. and needs a good italian tune and some good new fuel in it.

[booki89]

Hope it's as simple as a good old Italian tune up, the fuel is old, and tanks a bit low. So some fresh 98 probably wouldn't hurt anything.

How do I unstick the IAC valve? Is there a specific process or anything I should watch out for? Or just take it off and give it a clean.