I just picked up my car from the shop. I am getting very low egt's in the 500 degrees C range when im on the highway MAX. What could cause this besides the car running rich.

The CE light is also on, i havent had a chance yet to get the code, i will post it up here where i can get to the car.

 

where is the probe installed?

 

My best guess would be the placement of the egt probe. If you have low egt's then the timing is through the roof, or you are running rich. I still say its placement. Best place for probes is 1" from the head of the block on the manifold.

 

yeah, that probe has GOT to be 1-2 inches from the head of the manifold for a normal reading.

 

running very rich or a retarded ignition setting reduces EGT's due to incomplete combustion.

lean conditions increase EGT's, along with poor charge cooling.

 

Actually, a very rich condition would cause a high EGT reading.

 

why

 

what? why

 

Low Fuel cuases Low EGT

 

Cause the unused gas ignites in the manifold.

 

I was almost positive that a retarding ignition tends to raise EGT's....thats how it is in my car to a point.


[Modified by lshatchturbo, 7:45 PM 3/1/2003]

 

ok so the cylinder temps themselves are ridiculously low in this case, even though the manifold is heating up...i always assumed this was very rare and you'd start to get rich misfire before things got this bad.

retarding timing can raise EGTs. adding fuel lowers EGTs in the normal tuning / operation window of the engine. at the extremes all bets are off.

 

Retrding timing DOES increase egt's. Because the mixture is ignited closer to the point where the exhaust valves open.

 

damn alote of missinformation here
retarding will cause high to very high egt's
running rich will lower egt
running stoich will cause very high egt's
running very lean ,no more fuel =lower egt's
less gapping (spark plug)=higher egt's
i have experienced all of does

 

Hmm, well im my case, the low EGT is along with the CE light. The CE light went away by itself now. But the EGT's r still very low, does not go over 600 degrees C. So i reset teh ecu, but same thing. What could be causing this?

Could a bad distributor cause this in some way? I can tell my distributor is on its last breath, but coudl it cause the low egt?

Or indirectly, coudl the bad distributor cause the CE light which in turn cause the car to run in limp mode and cause a rich mixture?

 

He just explained why!


[Modified by lshatchturbo, 8:56 PM 3/1/2003]