Modified 6E code in an 87 Vette. My BLM is 134 at idle, but the exhaust smells rich. I can't hear an exhaust leak. I think I've got all the vacuum leaks sealed up, but I don't think they'd make such a rich condition. I'm working on my WB to sniff the exhaust to find out what it really is, but until then, any ideas?

 

try another O2 sensor.
Or if you have a scope put that on it, and see if it's *lively*.

A dieing O2 can indicate lean so the ecm will add fuel.
134 aint too bad.

 

Hmmmm....
the $6E code seems to have this inherent lean idle problem. I see it often on the scanner myself. However, once you tip in on the throttle it'll snap back to 128/128...at least that's the way mine does it. I have seen 145 and higher @ 750 RPMs (Idle) but I have a feeling that this was done for a reason...namely emissions testing. I could be wrong but everyone I've ever talked to has the same phenomena with the $6E.

One of 2 cures for this problem...
a) make some battery voltage corrections

-OR

b) tweak the MAF scalar table 1 little by little until you get 128/128 on the scanner.

I don't pay it any mind anymore now that I see about 134-137 on the scanner...

HTH,
Brian P
89 IROC-Z 355

 

I have been fighting the same problem except on a greater level.
Mine will slowely raise to 160,but soon as i hit the gas 128.
it also seems crusing and low steady rpm this will also happen
but not maxing out blm - just around 148.
as a quick test ive tried raising FP to 55lbs and still the same.
I have heard that the smallest of leaks after MAF can cause that to happen,I havnt ruled that one out yet for myself.

p.s.
I just got pocket programmer yesterday,ordering zif and flash
prom today.

 

O2 cross counts are good and the sensor is less than a year old. It could be the culprit though, because idle smells very rich.

 

Heated O2? Running headers? Bone stock?

 

Unheated O2 in stock location after stock headers - balanced blueprinted L98 with highly ported heads and intake - 218/226 .510 114 LSA cam. Very choked up exhaust.