Missfiring, Need Help !
08-13-2006, 08:26 PM
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Missfiring, Need Help ! I just bought the car and on the 7 hour drive home it ran fine and didn't mis one time but had the SES light on the whole time, the first time it did it was the night i got it home (after the SES light turned off) home and since then it keeps happening, at around 2500RPM moslty in 3rd the tach and speedo with both begin to "bounce" the SES light will flash on a off quickly and the car with "buck" all at the same time. The code it is throwing is p0330
The car is NOT tuned for WOT and the cruising tune that is on it know was done by an "expirienced" but not proffesional and I am wondering if maybe something could have changed in the tune during the 7 hour ride home?
I am going to be doing a Head/Cam swap soon and have the car dyno tuned by Rapid, but I would really like to know if anyone has any ideas on it now.
Thanks, Matt
The car is NOT tuned for WOT and the cruising tune that is on it know was done by an "expirienced" but not proffesional and I am wondering if maybe something could have changed in the tune during the 7 hour ride home?
I am going to be doing a Head/Cam swap soon and have the car dyno tuned by Rapid, but I would really like to know if anyone has any ideas on it now.
Thanks, Matt
08-15-2006, 08:50 AM
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You have a misfire at this RPM & load, maybe too
much advance (for the fueling and/or fuel quality)
at this load-point. Do you know if this is closed
loop (likely a timing surplus then) or open loop?
Might check over the engine for any hung-on
"voodoo mods" that can be removed and get a
little less advance or more straight-up air/fuel, at
least get you more drivability until you can get it
tuned right. Maybe clean the MAF, etc. and check
the plugs & wires. Especially if there are also any
issues at higher load / RPM (where misfire detection
is on a smoke break).
much advance (for the fueling and/or fuel quality)
at this load-point. Do you know if this is closed
loop (likely a timing surplus then) or open loop?
Might check over the engine for any hung-on
"voodoo mods" that can be removed and get a
little less advance or more straight-up air/fuel, at
least get you more drivability until you can get it
tuned right. Maybe clean the MAF, etc. and check
the plugs & wires. Especially if there are also any
issues at higher load / RPM (where misfire detection
is on a smoke break).
08-16-2006, 08:32 PM
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I have HPtuners and know how to use the program. although i am unsure of how to tune the car. If you are saying to pull the timing back a little(how much?) or change the air/fuel I could do either with the tuner but I just dont undestand why it would be fine for the 7 hour drive and then begin to act up?