That would be the third check and clean then


Standard gasket, IACV leaks coolant whenever I unbolt it, so it shouldn't be blocked I think

How would the head be modified for not having coolant flow? It did have ITB's, yes.


Just drove it around a bit more and it might be my imagination.. but it seems to drive pretty normal. I also filled her up with some fresh fuel.
Low revs still don't feel like it should, but it's not a big difference. Higher revs also feel quite normal, and it does pull rather nice now without hesitation.

Idle is probably still a problem though, don't think it will solve itself.

 

Disconnect the knock sensor today to rule that out as well. Didn't make a change... didn't gave a CEL either??

Got some movies as well.

Idle, with idlescrew turned up a bit:

http://www.youtube.com/watch?v=cDVLJAtSSk0

 

This is where I try to keep the revs constant without moving my foot. You can see the revs slowly dropping and then rising a bit without me actually moving the throttle. The big dips is me ofcourse.

http://www.youtube.com/watch?v=T4inR_NAAvk


This is with the idlescrew of the throttlebody turned down again. This is the original problem.

http://www.youtube.com/watch?v=xZSatBpSIeE

 

Anyone?

Car also backfires when releasing throttle at 5000rpm in neutral. (not loud, but the exhaust pops, didn't use to do that)

 

Reinstalled the cat to see if it would pop a CEL... nothing.

At WOT everything is alright, pulls very strong without hesitation.
Every other throttle position and it will hesitate and jerk about. Also slightly shaky when idling (at 900rpm approx.).

I can also make an OBDII log of all the ECU and sensor values with Dashcommand, anyone that knows how to read these values?

 

No vac leaks? idle fuel pressure good?

 

Checked for vac leaks with brake cleaner... engine didn't respond.
The idle doesn't change either when I pull off one of the hoses though.


Don't think I can read idle fuel pressure through OBDII?


This isn't just an idle issue alone, considering the fact it also drives with hesitation and jerkyness with mild throttle.

 

That would make me think there is a vac leak somewhere. You should hear the engine rpm increase when you remove a vac line.

 

It doesn't...

There aren't that many vac lines, so it should be pretty obvious?

The most right one of the 3 vac lines on top of the intake came loose during some tests last week without me noticing it. It wasn't untill I drove with it that I noticed something was not right, the idle would jump from 1200rpm to 2500 rpm all the time... as soon as I connected that line everything was back to normal. Well... "normal" as it is now.

 

Maybe run some fuel system cleaner?
In the first and second video it looks normal.
In the third it doesn't but the reaction in rpm on the fast blip of the throttle is nice.
The fact that it stalls points to idle control IMO and I can't think of anything else.

Is the car driveable in traffic?