cause of surge with locked ignition and valve in warm up.

[Foxbodyguy49]

so in trying to figure out a idle surge i went and put the car in warm up mode and made all the ve cells the same and the timing as well in idle area but im still getting a swing in RPM. ive looked for vaccum leaks and havent found any. what would cause only my pulse widths and AFr to fluctuate and my idle swing.

 

[a91what]

watch the load value move in the VE table, is the AFR table flat in those same cell areas?

The VE table may need to be altered to keep the PW relatively flat when this occurs.

you can also try richening the VE map a bit, sometimes the oscillation will smooth out with a bit more fuel. 13.8ish usually does the trick but smells so I try to shoot for 14.4ish

you may also have an idle valve that is not holding position.. if you remove the valve or make a block off plate for it and it will idle steady with the throttle screw setting then the valve is the issue

 

[Foxbodyguy49]

watch the load value move in the VE table, is the AFR table flat in those same cell areas?

The VE table may need to be altered to keep the PW relatively flat when this occurs.

you can also try richening the VE map a bit, sometimes the oscillation will smooth out with a bit more fuel. 13.8ish usually does the trick but smells so I try to shoot for 14.4ish

you may also have an idle valve that is not holding position.. if you remove the valve or make a block off plate for it and it will idle steady with the throttle screw setting then the valve is the issue

Are you still available for tuning classes?

 

[a91what]

I am, I wont be available until after 8pm eastern during the week. or we can schedule a weekend

 

[Foxbodyguy49]

okey sweet ill PM you tmmrw to schedule