Hey guys... I posted this on TPI and Tech, but noone answered, so I guess Ill try here.
To make a long story short, my car isnt running good. It has a constant rough idle, nomatter what I do. Ive thrown coded 43, 44, and 34 previously.
I finally get the car on a scanner, and heres what I get.
-Blms are right around 128-131
-O2 is @ 795, WOT. Pretty lean.
-Knock is being detected.
-16* of total knock retard.
-HERES THE KICKER... 39* SPPARK ADVANCE NOMATTER WHAT THROTTLE. IDLE, OR WOT DOESENT MATTER, STILL 39*.

Does my ECM sound shot? Beings that the 92 ECMs have the EST's built in, thats the only thing I can think of. Is this controlled by the ECM itself, or the acual Prom? Something on my prom doesent look right, but beings that this is the only SD car Iv had, I have nothing to physically compare it to. Now, Ive gone over EVERYTHING except replacing the ECM, because money is tight at this point.

Hopefully this makes sense... Im sick, and the medicine is makin me a little goofy, but any help is appreciated!
-Rob

 

Hmmm, this don't sound right. I think 43 and 44 are lean and rich O2. Also, 34 is high MAP? But you say BLM's are fine. The SA not changing doesn't jive either. I would say the data is corrupt in the prom but that is just a wild guess. Might be a bit of a reach, but not impossible. And I'm being picky but EST is spark timing which is controlled in the ecm by the prom in every car. ESC is also in the ecm but on the 730, the ESC module is mounted to the memcal. EST= spark timing, ESC= spark control (knock).

 

You say its mounted to the prom... When I look at the prom, theres an extra chip ontop of it, that isnt there on an older style prom... is this what your talking about? If so, there seems to be something wrong with this chip, almost like burned terminals, but as I said, i dont have another SD chip to compare it to... anyone have a pic of a good one?

 

oh yeah... 43 is Knock Sensor, 44 is o2, and 34 is EGR. I had a Hyperjunk thermomaster in there, and I removed it, but that didnt help any.

 

I guess I also should mention that after about 10 minutes, the scanner could no longer communicate with the ECM. It would keep freezing, and I got a corrupt data error once. Sorry for the choppy replies, but Ill keep adding things as I remember them. I think I just about covered everything.

 

Ok, heres something to better help. This is a pic from Traxxions archives. Now, I have marked off, in red dots, what I see on my chip. Im seeing purplish specks where I have marked in red. What do you think these specks Im seeing are?

(origonal pic) http://pic3.picturetrail.com/VOL18/9...45/1138119.ptp

What Im seeing...

 

Well, I went ahead and ordered a brand new chip from GM for $40 and change... Ill post the results when the stuff gets here... Any other ideas meanwhile?