RUNS!! but only for 3 to 4 seconds at a time.

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saberry0530
MegaSquirt Newbie
Posts: 10
Joined: Wed Jul 06, 2011 7:00 am

RUNS!! but only for 3 to 4 seconds at a time.

Post by saberry0530 »

plug change.msl
CurrentTune.msq
After numerous adjustments and problems it has now come to the point that it does start and runs but for only 3 to 4 seconds at a time. i have reached the end of my tuning knowledge and need some one to find me that tree cause all I see is forest. Attached is the MSQ and last plug change datalog. Thanks, No Many many many thanks
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WASyL
Helpful Squirter
Posts: 102
Joined: Tue Dec 16, 2008 7:46 am
Location: Warszawa - Poland

Re: RUNS!! but only for 3 to 4 seconds at a time.

Post by WASyL »

I assume that your engine is SBC350 with TPI system so why have you not enabled any Idle Control ? that might be a problem, trigger offset 10.7 ? and max spark duration 25.5? try rather 1.5-2.0 msec
also i would go with a bit more spark advance at idle

best regards
Pontiac Firebird 305 LT1 intake, L82 cam
MegaSquirt II with mod's + TPI adaptor board, MSExtra 3.3
saberry0530
MegaSquirt Newbie
Posts: 10
Joined: Wed Jul 06, 2011 7:00 am

Re: RUNS!! but only for 3 to 4 seconds at a time.

Post by saberry0530 »

WASyL wrote:I assume that your engine is SBC350 with TPI system so why have you not enabled any Idle Control ? that might be a problem, trigger offset 10.7 ? and max spark duration 25.5? try rather 1.5-2.0 msec
also i would go with a bit more spark advance at idle

best regards
THANKS WASyl!! As soon as I get back to the car, I'll make those corrections. I disabled the IAC just in case it was opening too much and causing the car go to lean. I richened the mixture by 30% across the board and WALLAH it started right up. , But it is still backfiring a little bit at idle (1100RPM )and a whole bunch when applying any throttle. I think that it will work itself out once I get the dwell and timing issues corrected. Anyone think that the 25.5 duration would cause the abnormally low dwell (1.2) and the backfiring?
WASyL
Helpful Squirter
Posts: 102
Joined: Tue Dec 16, 2008 7:46 am
Location: Warszawa - Poland

Re: RUNS!! but only for 3 to 4 seconds at a time.

Post by WASyL »

well play with IAC and Warm-up enrichment to make good idle, as for dwell i use around 2.0-3.0ms and it is just fine

best regards
Pontiac Firebird 305 LT1 intake, L82 cam
MegaSquirt II with mod's + TPI adaptor board, MSExtra 3.3
saberry0530
MegaSquirt Newbie
Posts: 10
Joined: Wed Jul 06, 2011 7:00 am

Re: RUNS!! but only for 3 to 4 seconds at a time.

Post by saberry0530 »

Actually running well now. To well and scary. Going to have to get new stickyer tires for the rear-end. Every time I go past 20% Throttle, it breaks them loose. Going around corners is especially worrisome. THe things we have to tolerate.

Still need to take it out on the highway and get some logs and O2 readings for larger throttle positions but overall not too bad. Thanks for all the help.
WASyL
Helpful Squirter
Posts: 102
Joined: Tue Dec 16, 2008 7:46 am
Location: Warszawa - Poland

Re: RUNS!! but only for 3 to 4 seconds at a time.

Post by WASyL »

good to hear, i change my semi-slick Toyo R888 every few days for new ones :mrgreen:

best regards
Pontiac Firebird 305 LT1 intake, L82 cam
MegaSquirt II with mod's + TPI adaptor board, MSExtra 3.3
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