Ever since I put in my LT4 hot cam and LT's I have had a miss that won't go away. It is intermittent and very annoying. Yesterday (after I fixed my ABS) I decided to switch my wide band 02 from the pass side exhaust to the drivers side. I have been tuning with the 02 there (on pass side) for 2yr and have gotten the A/F very close to perfect. When I made the switch the readings were 16/1 A/F ratio and even more lean at times on the drivers side. WOT is around 13.7. I figure it must be either an injector not working properly, bad drivers side 02 (both were brand new and heated after I did the LT's) or the computer. Any thoughts?
I have switched injectors from the new ones (bosch III's from FIC) to the old ones and it made no difference. Also I split the pass side 02 wire and ran that back to the computer for a while and also no difference. I am leaning toward something wrong with my ECM. I have a new Delphi 02 on order so I will replace that and see what happens.

that is odd... what is the BLM doing? And what about the knock sensor? Could you be losing timing?

Split blms seem very common in the lt motors, I have read about a lot of cars having that prob. I will research later for you.

I'll check my last data log and see, I know I have a lot of knock counts.

have you considered upgrading to LT4 knock sensors? They are designed to ignore the rattle from the roller rockers.

Quote:
I didn't realize there was a difference, I have the hot cam and roller rockers plus LT's, lots of opportunity for noise. I will check into that.

Well I eliminated one third of the possible cause of the problem, the injectors. I sent them back to FIC to be flow tested and cleaned, they all flowed fine. So it must be either the 02 sensor or the ECM in my thinking, is there something here I could be missing? By the way FIC is a great company with great service.

Quote:

Bogus I did some research on this and I believe that the LT4 knock sensor is really a knock module that was added to the 96 ECM to reduce the sensitivity of the actual knock sensor, does this sound right? Also check me on this; my problem is drivers side very lean (16.0 and up), pass side normal (14.7). If this were caused by timing being pulled why would it effect only one side and not the other? Just asking to see where you are going with you thinking.
As to BLM's they are split but still very close. I can post my latest data log here is that would help.

that is odd that there is such a difference in left/right banks...

and yes, it's am module of some sort, but it can be installed. I don't know the details, tho.

I will have to think more.

Ok problem finally solved. It was apparently the 02 sensor on that (lean) side. It's only 2 yr old, no codes related to it and it was working on the data log but when I replaced it today everything is back to normal, both right side and left side running 14.3-14.7 on my wide band.
Now my service ABS light is on, it just never ends with these cars, haha.

you got that right!

Congrats on the fix!!!