fiero exhaust manifold problem

[FieroGT86]

my fiero engine gets super hot and you can see the exhaust manifold turn orange color when it gets to its regular temp and when i drive it for about 10 to 20 mins, my car idle meter jumps up and down and it seems like the engine is about to die and when it gets super hot my engines just turns off. pls i really need some help.

[ctesla]

cat converter backed up?
built up carbon deposits on EGR or manifold runners, causing incomplete flow, and excess heat, without dissipating?
it's a GT, so only one side is "lighting up" right?
forward or rear one?
doing any off-roading, or curb smashing? is one of your exhaust pipes crushed?
you do have coolant in the radiator? and the aluminum transfer pipes from front to rear of vehicle are not crushed, correct?
did you do a tune-up recently? could you have crossed plug wires?
with a firing order of 1-2-3-4-5-6, a crossed wire (or inductive crossfire, if the wires are excessively old and internally broken down), or a wire laying/burning on the manifold could allow a no-fire/misfire, which would put the fuel sparking/burning not on a power stroke, but as it is exhausted, right into that cast iron log/manifold...
does it look like the manifold is cracked?
check these issues first;
hope this helps,
chris
nrt racing

...these are still minor compared to internal damage: any valve train noise?
a miss? a lope? off-idle? or just runs ok for 10-20minutes, gets REAL HOT, shuts down?
how many miles?

[FieroGT86]

both side of my exhaust manifold glows and i think thats the reason why the engine cuts power because the engine compartment gets so hot that it makes my car miss fire. and also i found out my front exhaust manifold was leaking, but i dont think thats a reason itll heat up like that.
ill try your advise and ill tell you how it went. thnks for your time hope you can help me later on again.

[ctesla]

Originally Posted by FieroGT86

both side of my exhaust manifold glows and i think thats the reason why the engine cuts power because the engine compartment gets so hot that it makes my car miss fire. and also i found out my front exhaust manifold was leaking, but i dont think thats a reason itll heat up like that.
ill try your advise and ill tell you how it went. thnks for your time hope you can help me later on again.

if BOTH are glowing it definitely sounds like exhaust disruption.
back her up on ramps, and disconnect your "Y" pipe, and let it idle in the drive (yea, it'll be loud) but if the logs don't glow in 10-15min. you have a bad cat and/or muffler.

hope this helps,
chris

[FieroGT86]

aite sorry i forgot to tell you that i just recently replaced my cat wit a straight pipe(down pipe) but i think my mufflers is bad because i took all my exhaust piping out before and when i lifted the muffler you can hear bunch of little piece or metal inside the muffler. will this be the problem because i cant think of anything internal part will do this type of problem.

[ctesla]

replace muffler with glasspack, turbo muffler, or straight pipe.
enjoy.

chris

[FieroGT86]

glass pack? haha sorry i dont know what that is. But i got another question can i put a 4 cylinder exhaust piping with the muffller in my GT. i wanna make mine a single. go on the link below and look at it. thnks

[ctesla]

is there a reason for wanting to go with a "single out" rather than dual, other than price?

if that is the case, do not buy an entire cat-back system;
your muffler is 2-1/8" inlet and two 1-7/8" outlets.
try and find something equal to this, cut out muffler, and weld or sleeve and clamp in new one.

your exact fit muffler is a Walker#40094
the muffler for a 2.5L is #40199

call your local parts stores and price, I would still try for the dual for the V6, you can probably go with the single out, as BOTH 4 and 6 cylinder systems show the same inlet and outlet sizes.
the CLOSEST Walker brand "universal" type muffler you could buy, then take to a muffler shop to weld-in, or purchase sleeving flanges and clamp in yourself is a part# 18104 :
this is an oval muffler casing with the length of the body of the case being 20" in length; with a single inlet of 2-1/4" and two outlets on
opposing sides, directly across from each other (one on the same side as the inlet) with a diameter of 2" each.
the overall length of muffler case and entry/exit ports is 28" (about four inches on each side of pipes)
the OVAL parameters are : 4-1/4" overall heighth and 8-13/16" in the width.
this might be a tight fit, but you might be able to yank some heat shields out, or bend them out of the way, and maybe cut the original pipes farther away from the original muffler, to squeeze this one in.

this part can probably be ordered from a local parts house near you, and will most likely be under $45. (possibly less than $30.) flanges and clamps(if you elect to fit it yourself, another $15-20, and maybe buy $5 worth of hacksaw, or sawzall blades) and then all you need is patience, or a hammer.
if you call around locally, you can probably find a welder in a muffler, or independent shop, that will cut and tack it in there for $45-85. (depending on what side of town you live on)

if you want the same specs (maybe a little smaller in the casing size) but a performance muffler :
Walker/Dynomax #17739 is the Super Turbo muffler or
#17266 is the Ultra-Flo number
(these will probably be about $50.)

now: wanna know what this fits? '75 Pontiac Ventura!
and 'mid 90s Jeeps with 2.5L and 2.8Ls!
just because you own a Fiero (or a Corvette) doesn't mean the parts should cost more.


hope this helps,
chris
nrt racing

[ctesla]

sorry, forgot,
websites for pictures, specs, and measurements:

walkerexhaust.com

or dynomax.com

chris