On my way home 35 miles from my mechanic friends house, had a high RPM miss around 5700-5900 (I think) when I would get on it. We had finally gotten the car finished after installing the RK Sport headers and Y-pipe, NGK TR6 platinum plugs, Moroso Blue Max wires and MSD cap and rotor. First time it's been on the road in 3 weeks. Any ideas?

There was no miss previously.

The car is running open Y-pipe at the moment. Does that have anything to do with things? What do you think? My friend will look at it as soon as I get ahold of him, just looking here to get some opinions or ideas I could bounce off of him. He did hose off the front of the car really quick earlier today (there was power steering fluid on the front of the block.

 

ttt

 

just a thought, but are you sure you didnt just bounce off the rev limiter in first or something? the tachs are known to be too slow for the motor when in first gear so it always reads a little low and next thing you know your bouncing off the rev limiter. good luck.

 

did you install an LT4 knock module during the header install? if not you probably should for the extra noise, but i dont think the stocker would cause the miss necessarily. unfortunately thats pretty characteristic of the old opti

 

What about a weak coil?

 

If you just put new headers and plug wires, check to make sure none are hitting or arcing, open the hood in a dark place w/ the car running and look for fireworks. Works for me every time.

 

After my header install, I had a hell of a time with burnt wires for 3 years, untill I installed OTVC wires and high temp heat sleeves. I can now pull from 1500 RPM in 6th gear. I couldnt dream of that for the last 3 years. I would look closely at your wires, and install heat sleeves either way

 

Thanks guys

Well, I don't know if it was hitting the rev limiter, --it never did before (A4). Maybe the new headers and no backpressure is causing it to spool up faster than it's ready for? Hmmm I don't know. I did have that thought that it could have been the rev limiter... But I'm not sure.

Would it spool up too fast and get there? I believe it may just be happening in 1st gear come to think of it.

I'll have to look and see if anything is touching. As far as I know all was well when we finished turning wrenches.

No I didn't install a LT4KM. I didn't even think of that to be a possible reason. Thanks, keep the suggestions coming guys.

 

coil wire....... opti

 

im sorry i was thinking it was a 6 speed in which case i would say it could most definilty just be the rev limiter but less likely with an auto. i would say maybe coil or plug wires.

 

i have this same problem too. i get a high rpm miss right at 5700-5900. and it gets worse when i take the lid off my cutout. i think you may be right about it spinning up too fast for its self.

 

Yeah I installed 8" DEI wire sleeves right out of the gate. We'll have to check all the wires anyway though.

Thanks again guys. The thing that sucks is it's definitely something related to the work that was just done, because it never did this at all until after all these new parts were put on.

 

Just to revisit this thread... It was the transmission starting to slip. A few weeks later, it became very obvious (car refused to shift out at the top of gear).

Just got it back with built transmission, custom kit and stall, and all is fantastic.

 

wow, how many miles on the car?

 

104K