B6T won't stay idling

[Damkid]

I'm running out of ideas on my 323, I just got done dropping in a fresh B6T, everything piece of electronics from the old motor was re-used, intake, injectors, knock sensor etc.

On a cold start up it'll idle fine, once it get to operating temp it'll just die

At first I thought maybe my timing belt was out a bit, checked it and all good, then I thought vacuum leak, just got done pulling the intake and re-sealing it, all vacuum lines are hooked up etc. I'm running out of ideas as to what to check for

Anyone else have any ideas??

[Advancedynamix]

How old is the gas? What is the idle screw set at? Did you forget any rags in the intercooler plumbing? I know your on top of that stuff Chris, this is pretty much a list of things I've had problems with in the past while swapping engines. It's probably something simple.

[Damkid]

It's got fresh gas (filled up last night) the idle screw wasnt touched and since it's the same intake from the old motor, which ran fine, so I don't think that's the problem, I've probably driven it about 45mins drive time with this motor so far

I've gone over as much of the simple stuff as possible but still no change

[Damkid]

Oh I should also mention the car feels down right lazy, I don't see 10psi til like 4k rpm (stock turbo) which is why I thought vacuum leak or timing belt

[koRnhead]

Have you checked for boost leaks? Perhaps one of the cold side pipes isn't tight......

[Damkid]

Yup checked the charge pipes, all good there

[bhazard]

Didn't you own like the FIRST b6t festy? Lol

[Damkid]

It was the SECOND B6T festiva, jeez get your facts right :p

[Damkid]

Well I talked with the guy I got the 323 from, he said he always had an issue with idling, and what he found was a loose connection at the VAF, which he zip-tied the connector tight to the VAF to fix it.... When I pulled the motor I cut off all the zip ties, so I'll put some back on to see what happens

[shadetree]

Mine was a leaking blow off valve , that i didnt hear . Im deaf anyway !!

[M3NTAL]

Lazy could mean an injector is clogged

I remember on my truck it made 400 hp with 7 injectors(1 clogged) lol but 558 @14lbs with 8 lol

[hodginsa]

Technically it should idle(limp mode) if you unplug the VAF, but maybe not. Does it sputter and die? or just fade off.

[Damkid]

Well it ran fine with the old motor and it's the same injectors so I don't think that I got one that's stuck or anything but at this point I have no idea

At this point I'm getting so fed up with stupid B6T's it would have been easier to rebuild the old motor at this point, so if I can't get this POS to run right.... Well.... I have a spare KL sitting in my garage, I know it ran mint

[FestYboy]

carbon buildup in the air bypass screw port? you state that when cold, it idles fine (IAC is working), once warm it stalls (IAC is out of circuit once engine is warm). also, look at your IAT voltage output (ignored when cold).

[Rocketman]

Technically it should idle(limp mode) if you unplug the VAF, but maybe not. Does it sputter and die? or just fade off.

Nope... VAF is a critical ECU input. The fuel pump switch is in there too, so without it - no fuel.

Chris - Vac leak would be my guess. Also, have you tried messing with the spark timing? It needs to be set with vac removed from the dist. This can cause idle issues & lack of power if it's not set right.

VAF plug might cause it...

Try bumping the idle with the setscrew for the time being & see what happens