1993 GMC 5.7 TBI Strange Idle/Driveability Problems

[TylerZ281500]

it should not be 4 degrees advanced, mine is built more than most peoples here and its at 0 doesnt always have to be advanced, you habe to play with it

 

[unclegrandpa5144]

So much for your Chevy knowledge

 

[unclegrandpa5144]

When u build it 0degrees, run it at 4

 

[93SierraZ71]

I could try playing with it and seeing if I can find a sweet spot. I will also check that knock sensor. I checked all the wires off the computer and everything looks good. I also checked the wire to the knock sensor and its fine. I put some electrical contact cleaner on the plug to it as well. When you unplug that thing you unplug to time it, it improves the driveability slightly (no stalling or anything)

 

[TylerZ281500]

when you unplug the knock you somewhat disable timing advance, its just guessing that theres no knock counts.

 

[unclegrandpa5144]

Check timing

 

[unclegrandpa5144]

Waiting to hear what u found timing was at

 

[93SierraZ71]

Waiting to hear what u found timing was at

It was at 12 degrees advanced awhile ago but I put it back to 0 degrees when I put distributor in.

 

[unclegrandpa5144]

Thanks 4 reply. OK. 12dgs bit much. It should run strong at 4 dgs. 6 is OK too. That yr motor has a couple of disconnects before u get to set timing. Also did u check for chain stretch. Anyway ,how's it run now?

 

[unclegrandpa5144]

I hope u got a book that covers that year motor controls and related adjustments