S&S 3400 header pinhole from the factory.

[SappySE107]

If it was the tune, it would be worse before close loop, don't you think? There are really only 2 variables I consider. 1, forged pistons and not enough clearance so it seizes up when its warm. 2, exhaust leaks before the O2 sensor (which is 3 inches from that bung with a hole in it).

[3400-95-Modified]

I've had issues where my open loop start up is fine but once warmed up the car will not properly idle due to many other ECU variables that I had to f-with. But as you noted with the complexity of this motor(just rechecked his build thread) there are many other things that could also be causing it yes, but I really don't think this one hole in the exhaust is enough to do that. For his sake I do hope I'm wrong though.

[blackbombshell95]

The crossover donut was leaking also. I tightened that up a bit and its better now. IIRC 3400 modified you use to have the same cam correct?

[SappySE107]

Nope, you are the only one with that cam.

[3400-95-Modified]

Only other cam I ever had was a Milzy stage 1... My donut gasket was leaking all the time which is why I put a v-band clamp there and my O2 was actually in that bung and I never had issues. Are you running the ECU using the narrowband output of a wideband O2 sensor?

[Fireball]

Do you have pics of the setup 3400-95-Modified?

I don't want to thread jack at all but like the OP and anyone with S&S headers, it's always a war to keep the bastards sealed!

[3400-95-Modified]

[3400-95-Modified]

Stupid me, I also realized his hole is in the EGR bung, not the O2 bung, hence why I was wondering why there was no O2 sensor screwed into it.

[blackbombshell95]

Nope, you are the only one with that cam.

geldartb has the cam.

[Superdave]

Its right before the O2, which is going to throw off the readings. Makes sense to me that it fucks up in closed loop.

Agreed, seen it lots of times.


There may be other problems as well but getting a false lean signal to the o2 and flooding the engine with fuel will really piss it off.

and +1 for V bands, I will never again use anything else. worth every penny.

[blackbombshell95]

I'm talking with a few friends to try and get this pinhole welded by next weekend .

I <3 smoke machines :-D

[ericjon262]

I'm talking with a few friends to try and get this pinhole welded by next weekend .

I <3 smoke machines :-D

DIY

http://www.theturboforums.com/threads/363900-DIY-smoke-machine-tester!?highlight=smoke+machine

[pocket-rocket]

DIY


http://www.theturboforums.com/thread...=smoke+machine

That's pure win right there.

Sent from my HTC One X using Tapatalk 2

[Alxsmt]

I dont think mine had a pin hole there. however, on the rear header where the crossover is welded to the primary, the weld literally fell out leaving a hole.. I hate s&s headers..

for your idle issue, try adjusting the idle screw. seems stupid, but I had idle issues for years. the guy doing my tunning couldnt tune out for anything, finally he adjusted my idle screw.. problem solved! IAC couldnt move fast enough to cure it. might be worth a shot

[3400-95-Modified]

I've noticed with the TCE TB's you should adjust the plate so it's just off of getting stuck in the bore. If you have the TB out you can feel the plate sticking when you adjust it that far closed, then just open it up till that feeling goes away then give it just a bit more. If you have it too far open it will cause high idle issues and the IAC wont be able to even stay open at idle. I've got mine setup pretty good right now and is open about 20-30 counts at idle. I could even go a little further open with my throttle plate and idle the same.