Red Hot Exhaust Manifold

Im having somewhat the same problem with my chevy cavalier 85, 2.0
liter. The exhaust manifold lights up bright red after running for a
few moments. My friend had told me to un-hook the catalytic converter
from the pipe and see if it would get hot. When i looked under the car
i didnt see the catalytic converter. I looked up a picture to make
sure i knew what i was looking for, but found nothing. Timing was
right on and everything, it doesnt seem that the timing chain could
have slipped at all either. Im still stuck on this whole thing.

 

The cat is a muffler-shaped device located on the exhaust pipe towards
the front of the car, usually about where the driver sits. If you follow
the exhaust pipe from the engine to the back of the car, you should
see something muffler-like before you get to the actual muffler at the
back of the car. But removing the cat won't solve your problem, and
it's not easily removed on most cars.

If you've been following this thread, you'll see that the red glow is the
result of continued combustion in the manifold. This can be caused by
many things, such as base timing being off, not enough advance at
higher rpms, too rich a mixture, or an air leak into the manifold. If the
glow is that obvious and you really don't know what to do, take it to
your favorite mechanic and let him have a go at it.

 

Awesome advice there, i think that you have shinned the light upon me!
i veleive the problem happend after i did a tune up, but i changed it
back to where everything was set before the tune up (including putting
the old cables, cap and rotor on) seems to be really sluggish, i cant
get it to go over 15 mph in first, and it gets up to 25 in a five mile
stretch. ive noticed that it could just possibly be a leak then. ill
take a look at everything again, Possibly check if im runnin too rich.

 

Hi Bob
Hope you had a nice Christmas, I did. Sorry I haven't gotten back to you
until now, it's been nutzzzz around here, I haven't had much time to myself
lately. I'm not even sure if you're even looking at this post anymore.
Anyhooooo, thanks for all the help, I'm going to leave the car the way it
is, it's not perfect, but at least I know that the exhaust manifold won't
get so hot that it will melt off!!!! LOL
As I mentioned before the problem has all but gone away. The remaining,
slight red glow (only when the car is driven faster then 110Kph) isn't that
bad at all. The remainder of the problem might be the Thermo to ERG valve,
but for now I'm going to leave er alone until I find out for sure.

Talk to you soon
Mike
PS funny story about your brother's doomed car. Funny thing is that the
Excell doesn't handle that badly, I know because I drive down, gravel back
roads, here in the country. Sure it's not a Porche, but it handles ok for a
small car : )

I'll check from time to time to see if you

 

You're quite welcome. I'm glad to hear things worked out well
enough with the Excel. The fact that it's such a reliable little car
once you've gotten all the kinks worked out makes it difficult for
my brother to simply junk his doomed one when all it seems to
need is (just!) 2 fenders, a front bumper and a passenger door
and a hood. In other words, with all the damage, it still runs and
drives great. FWIW, the first body shop he took it to didn't even
want to give an estimate.

Regarding your car, you might want to eventually buy a heat
shield for the exhaust manifold for about $20-30, just to protect
the hood and any nearby hoses and wiring when summer comes
around.

But right now, I have to figure out what to do on this balmy, zero
degree (F) day here in CT. Balmy for you, that is.

Later,
Bob

 

Seems to be working good so far. Car runs like shit when it's cold, just
have to wait until the car heats up a little bit to the cold mark on the
gage and it's fine. Pretty sure the problem is the thermo valve, as the ERG
opens when the car is cold (- 20 weather) going to wait until the summer to
work on that problem, but by then it won't be a problem. LOL
I was thinking about getting a new heat shield for the exhaust manifold, but
I can't, for the life of me loosen that snakey pipe that's attached at the
top, I had to cut the heat shield to get it off, when I replaced the head
gasket, what a pain!!!!
Anyhoo, I hope the repairs, turn out for the best with your brother's car,
good luck!!!

Mike

 

Do yourself a favor and pull off the vacuum hose to the EGR
and plug it, and see if there's any improvement. Those
thermal switches are a pain to remove because they can
snap off if you force them too much.

If there's a hot air door in the snorkel of the air cleaner, make
sure it works. And make sure that you're getting that extra
vacuum advance when the engine is cold.

I was going to suggest that you check out all the vacuum hoses
for leaks, but then I saw a picture of the vac hose assy. What
a nightmare! I just hope everything is connected to where it
should be.

Bob