I have posted a couple of times on this but here is an update. High RPM miss, 5500-6100.

REPLACED:

IGNITION: Optispark, plugs, wires, ICM, Ignition Switch, Coil, Coil wire.

Fuel: Racetronix fuel pump kit


Now the only other things i can think of are
1) Fuel Pressure Regulator
2) Fuel Injectors
3) Valve Float


I am having the mechanic pull a valvespring and have it tested to see if maybe that is the problem. Besides what I have listed, and assuming that none of the new parts that I put on are faulty. What else could it be!!!??? As always thanks in advance for the help.


Very frustrated and broke,
Chris

 

Im going to start working on mine next week. I hope its just a bad opti or wires (got new ones already). I will be checck back to this thread and i hope you find out what the problem is man!

I bet its something stupid like the lash is set wrong.

Best of luck and post up what the Mech. says

 

damn i was hoping you figured yours out by now... so you could give me an idea on mine.


my next thing is is borrowing a wiring harness.

 

Thanks guys I will definitely post it up when I figure it out... Is it a realistic possibility that my LT4 Valvesprings have gotten soft after 25k-30K of mileage on them and are now causing valve float??

 

I had a high rpm miss and it turned out that the screws holding the rotor to the base of the opti under the cap had backed off and one actually came all the way out. It wasn't even a year old and I bought it directly from the dealer

My advise to anyone that is changing or has the opti off is to pull the cap off and check the rotor to make sure it is tight. I Used red locktight on mine just to be sure. From now on I am even going to do it with brand new ones also.

to take it apart you do need a special GM torx socket and a very small torx screwdriver.

 

Well I would try that but I doubt that 2 opti's back to back were bad... That would not say too much for GM parts... Plus a shop is doing the work.

 

i feel your frustration i'm in the same position i would have to say valve float or opti......



here's what i'm doing i'm going to buy the delteq or ltcc setup and and pray all night and hope it fixes it or mybe just i'll burn the fu**':n car that should solve it huh

keep us updated on your progress

 

Damn seems to be a common problem... The guys at the shop its at are stumped too.... ****in LT1's.... Gotta love 'em and hate 'em. I'll keep you guys up to date.

 

Did the sho check for valve float and spring compresstion?

 

They had to order the tool to do it and its supposed to be in tomorrow(tuesday). So we'll see.

 

I had the same high rpm miss. After the head gaskets start to leak. I did replace the spring and new opti. since then I haven't had any trouble. I will tell you this, a small amount of oil gets in the opti from the opti driveshaft. There was a small amount of oil contamition in my when I pulled it apart. The guys over at Delteq told me about it.

 

did they check the injector's under load?
-b

 

I have the same proublem even got worse with all my lt4 up grades i think its my opti too. i have had so many proublems with my car this year its not funny i would like to burn mine too! Im going to be running Ltcc kit on mine im thinking

 

Any update on this yet

 

STILL waiting on the valvesprings, locks, retainers, and seats from Thunder Racing... I ordered them on thursday...