Looking for opinions on this issue.

Discuss General Motors (GMC, Chevy, Pontiac, Hummer, Cadillac, etc) tuning topics here. Request definitions, discuss parameters, etc.

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damanx
Posts: 8
Joined: Mon Mar 18, 2013 4:14 pm

Looking for opinions on this issue.

Post by damanx »

This past weekend, I installed a new complete distributor on my truck that has a 3.4 60v6 with a 2.8l TBI system sitting on top of it. The original distributor had a little bit more of vertical play in it than the new one, but seemed in good shape in regards to "rotational slop". (can't think of a better way to describe it.)

Got the initial timing set on it and started the tuning process again since it's been a while and there is more that needs to be done.

In any case, the 1st thing I noticed right off the bat is that the knock counts are doing something strange. One particular instance is starting the engine, TunerPro reporting 4 counts and all is good, but then after a few miles of driving, the knock counts reset to 0. I've never seen the ECM data stream reset the knock counts to 0.

I've also noted that I can't get the engine/ECM to knock. Not sure exactly what might be going on here. Not reporting any fault codes in TunerPro, check engine light isn't flashing.

One other thing I also did was install the latest version of TunerPro RT, but I can't seem to pin it on that because uninstalling and reinstalling a previous version seems to have no effect.

One thing to note is that I can get a knock count when I tap on the engine block near the knock sensor, so I believe the circuit is working correctly.

I can't help but wonder if there might have been an issue with the ICM in the old distributor in regards to the timing, or, maybe there's an issue in the new one that isn't setting any codes?

Has me scratching my head....
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