A car at work has the exhaust and cats removed, yet the exhaust manifold is still burning red hot.Why?

Question

Engine is a v8, no cats, and still has the factory exhaust manifolds. Higher mileage engine, newer plugs/wires, yet the exhaust manifolds burn red hot.`The engine sputters just a small bit and has roughly 90000 miles on it. It was also well maintained and has never been over abused.
Why is this?Please give a detailed answer, and thank you very much.

Answer 1

My first guess anytime and engine seems to be running hot is a too lean fuel mixture. The sputtering you mention is likely due to that very situation.
get some fuel system cleaner that has NAPTHA on the label. It is the BEST kind. If you can't find it at an auto parts store go to a Chrysler/Jeep/Dodge dealer and ask for it.
Use that cleaner very strong and if it doesn't clear up the problem, you might have to go to the dealer and have a diagnostic check run to determine if a sensor is failing.

Answer 2

This all depends on the kind of car. At an idle, no car should have a red hot exhaust manifold. If it does, this could indicate a clogged Catalytic Converter.

Answer 3

The car is probably either over-fueling or timing is advanced, or both.
Several causes for over-fueling
1) Oxygen sensor(s) out of spec or dead
2) Exhaust leak before the oxygen sensor(s)
3) Coolant temperature sensor out of range.
4) Dribbling injector
5) Fuel pressure regulator defective

there a re a host of other causes, but these are the most common.
Timing may have been mis-adjusted, or the distributor has been bumped, or is loose enough to move on its own.

Good Luck and Merry Christmas

Answer 4

Red hot manifolds are a sign of fuel burning in the manifold. Ignition timing is probably way off, retarded I think.

Saw it before when the drive pin in my distibutor broke loose. That one was a little hard to find.

Answer 5

good answer by ironhand, i say the car has no cat, what did you do with the o2 sensors? there are a few dummy sensors u can plug into the system to fool your computer, they are not desined for long time use, great for the strip but for normal driving they are not good, the engine will slowley go eather extreamley ritch or lean, and that can caus your problems

Answer 6

When timing and fluid levels are where they should be then your fuel to air mix is too lean. If it is a fuel injected computer controlled it could be everything from the fuel pump to fuel pressure reg to one of the sensors(right now their names escape me) Carburated engines need only to have the screws adjusting the air / fuel mix adjusted

Answer 7

maybe the Exhaust manifold is old and needs replacing...Usually a sign that something is going to happen to the engine

Answer 8

the intake is still gettin too much gas

Answer 9

you have a severely retarded engine, ( ignition timing )