• The site migration is complete! Hopefully everything transferred properly from the multiple decades old software we were using before. If you notice any issues please let me know, thanks! Also, I'm still working on things like chatbox, etc so hopefully those will be working in the next week or two.

glowing red exhaust manifolds

GTP Ryan

GTP Ryan

New member
ok so i have an 04 gtp comp g, on my way home from work earlier i stopped and got some gas. i bought 93 octance as usual from shell. i noticed if i floored it afterwards occasionaly my car wouldnt shift and would kind of stutter. so right before i went home i floored it again to possibly diagnose it and see if it did it again. not only did my car not shift but my check engine light started flashing and when i looked under the hood my exhaust manifolds were red hot for about 20 seconds. does this sound like a to lean or rich fuel mixture or a clogged cat?
 


When my cat was clogged my gt would only run for about 15 seconds then shut off... my guess would be too lean...
 


Could also be WAY screwed up timing. Don't ask me how I know...but ya. Just my rear bank was glowing red hot too...
 
My guess is a clogged cat as well. Sounds like heat from the exhaust is not flowing out as it should. THat back up is over heating the manifold (hence the glowing red color). And since the car is not "breathing" right, that is why it's starting to give performance problems.

If you have to replace the CAT, I would suggest a ZZP downpipe with high flow cat. It's a little more in price, but if you have the tools, it's an easy DIY (bolts right in with no problem).
 
It's like your car is constipated.

Basically.

Anywho...man...just get a 3" DP like teh gai saidz. High flow or not...I'd get one without a converter and just buy an o2 sim with it...that way you never have to worry about it again.
 
bluegtp91 said:
It's like your car is constipated.

Basically.

Anywho...man...just get a 3" DP like teh gai saidz. High flow or not...I'd get one without a converter and just buy an o2 sim with it...that way you never have to worry about it again.
Click to expand...

There is no O2 sim for the '04 W-bodies. GM changed the O2 sensor and all my research on that leads to no available O2 sim (to buy or DIY).
 


Oh well...I never read the specs...I just assume 97-03.

You can have it tuned out I'm sure...or just deal with the check engine light...because even HFC's toss the CEL since they flow better than a factory converter.
 


shawngtp said:
LOL ^^^
Click to expand...

2nd that motion.

FYI - My Monte is stock and I added a HFC early this last July, parked it for the winter early/mid-October. Never threw a CEL yet. Granted, not to say it won't. But I think I will have the PCM tuned before that happens.

Though, there is a none-PCM altering method used by a lot of folks with a HFC. Involved modifying a Sprak-Plug anti-fouler and spacing the O2 sensor out of the exhaust stream. Cheap, easy, and something I was considering if I had that problem.
 
Glowing manifolds can be caused by ignition timing being retarded as well. Which of course hurts performance greatly.

Just my 2 cents :)
 
You must log in or register to reply here.
Back
Top