High RPM Miss....
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High RPM Miss.... So I have been tracking this issue down for sometime now and I am lost. The car runs perfect, pulls hard, up until around 5K then it starts missing and bucking like I've hit a rev limiter. I've checked the plugs, gapped to .045, I have check the wires, one of the boot terminals was corroded, and changed the coil with a new Delphi unit. The Opti was rebuilt by the Ebay guy everyone recommends also. So what else could I check? I've checked the fuel pressure as well, around 40 PSI from idle to WOT (read that with a cam it can be a smidge less due to change in vacuum from the cam?) Anything else I can check before I burn this thing to the ground LMAO!
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I was going to opti but since you say the ebay guy rebuilt it....have heard nothing but good things about his optis
have you tugged on/moved the wires going into the 4 pin connector top of opti with the car running to see if the motor stumbles?
confirm all the grounds on DS head near coil are solid (read wire is not broken under insulation near crimp)
have you tugged on/moved the wires going into the 4 pin connector top of opti with the car running to see if the motor stumbles?
confirm all the grounds on DS head near coil are solid (read wire is not broken under insulation near crimp)
I’m still going to say opti. Had one do the exact same thing only at 6200rpm. Chased that problem for a year before swapping a different one. Changed the cap/rotor prior to no avail.
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yeah exact same thing when I bought the exploding wallet MSD opti several years ago. High RPM breakup
Op
have you contacted the ebay guy?
if you sent it back he could test it...assuming his stuff has a warranty
Op
have you contacted the ebay guy?
if you sent it back he could test it...assuming his stuff has a warranty
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Ok, i'll try and get a hold of the guy. I'll check grounds as well, but to be honest if its the Opti again i'm just gonna do the Torqhead 24X swap and be done with it. I can just get the bare bone kit and fab my own brackets anyway.
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From: connecticut
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^^^^possible. Although valve float feels like the car just stops making power aka "nose over" vs backfire which is more commonly associated with opti fail. But tired springs certainly will make the car feel like a stumble and won't rev higher
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Ahh okay a few years back I was definetly experiencing some kind of backfire and I would always let off the gas because it caught me off guard. That's a good example
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Thread Starter
12 Second Club
Joined: Dec 2015
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I was going to opti but since you say the ebay guy rebuilt it....have heard nothing but good things about his optis
have you tugged on/moved the wires going into the 4 pin connector top of opti with the car running to see if the motor stumbles?
confirm all the grounds on DS head near coil are solid (read wire is not broken under insulation near crimp)
have you tugged on/moved the wires going into the 4 pin connector top of opti with the car running to see if the motor stumbles?
confirm all the grounds on DS head near coil are solid (read wire is not broken under insulation near crimp)
Thread Starter
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Usually valve float presents itself as power quickly falling off and not really sputtering. Ignition breakup and valve float can be easily detected on a dyno, if that’s an option.
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Something else to consider.... If I only give the car say 90-95% throttle, it wont break up and power through where it normally does. pulls strong through it also... This makes no sense to me...
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From: connecticut