2010 Silverado coil ground locations help (Misfire)
07-31-2023, 01:28 PM
#1
2010 Silverado coil ground locations help (Misfire) Hey folks,
I began tuning this over the weekend after the owner got the trans harness sorted out. The 4L80 swap seems to be working perfectly.
His main complaint about the truck was a stumble at heavy part throttle. The truck has seen a couple different tuners apparently.
Well, it wasn't a stumble issue, it was an obvious misfire situation.
Added misfire to the data log, all 0's. Hmmm. Look at the tune and the tables had been maxed out.
After restoring those tables, I can see that the driver's side cylinders all have multiple misfires. The other cylinders do as well, nowhere near as many, but the cam is rather large, the tq converter is lighter etc, so not unexpected.
Turns out this truck was LS swapped from the original 4.3L. The new ECU is from a 2010 4.8L. The engine harness is supposedly new.
So where are the grounds for the coils on these? I don't have access to the truck currently, so I can't look. He tells me he can't find them either. Just one ground bundle on the front of the pass side head. I believe that bundle normally goes on the side of the pass head and there is a single wire that is supposed to go to the rear side of the head, and another single wire on the driver's side that goes to the back of the driver's side head.
I'm thinking this is likely a loose ground for the driver's side coils. Especially since this is a swap situation.
Any ideas guys? Its certainly possible GM moved these around depending on the year of the truck.
Thanks,
Ron
I began tuning this over the weekend after the owner got the trans harness sorted out. The 4L80 swap seems to be working perfectly.
His main complaint about the truck was a stumble at heavy part throttle. The truck has seen a couple different tuners apparently.
Well, it wasn't a stumble issue, it was an obvious misfire situation.
Added misfire to the data log, all 0's. Hmmm. Look at the tune and the tables had been maxed out.
After restoring those tables, I can see that the driver's side cylinders all have multiple misfires. The other cylinders do as well, nowhere near as many, but the cam is rather large, the tq converter is lighter etc, so not unexpected.
Turns out this truck was LS swapped from the original 4.3L. The new ECU is from a 2010 4.8L. The engine harness is supposedly new.
So where are the grounds for the coils on these? I don't have access to the truck currently, so I can't look. He tells me he can't find them either. Just one ground bundle on the front of the pass side head. I believe that bundle normally goes on the side of the pass head and there is a single wire that is supposed to go to the rear side of the head, and another single wire on the driver's side that goes to the back of the driver's side head.
I'm thinking this is likely a loose ground for the driver's side coils. Especially since this is a swap situation.
Any ideas guys? Its certainly possible GM moved these around depending on the year of the truck.
Thanks,
Ron
