Thread: Stutter/Miss on higher than stock Boost.

I have an Avenir DET, Stock with aftermarket BOV and IC set up.

I Brought a Gizzmo Boost controller.

The car runs flawless on stock boost, but when i increase it i get a miss/stutter. I can make it happen as low as 8.5PSI

I am not running out fuel as far as consult can tell me, I have ran it at about 12psi and still in the low 90's % duty.

Im running stock ECU and maf.

So far i have:

Changed the coil to a known working one.
Checked the Gap on my plugs - They are 0.76mm
I have examined my dizzy but TBH i have no clue on what to look for under the cap.




I am getting the car tuned soon but i don't think its a stock tune issue as i have friends with similar set ups running up to 15psi on stock ecu.

Does anyone have any ideas on what to check/replace to try fix this problem.

i know your cap needs changing for sure, sorry i dont know whats causing your other issues

Thanks. Will be getting a new cap today.

ill also add:

When im on the high way doing about 100k (60m) set to about 12 psi. If i do a 5th gear pull no stutter. But if i drop to 3rd thats when it stutters so it seems its more of high RPM + Boost = stutter for me :s

are you running too rich?

It doesn't look like it. Readings on consult are fine, colour of the plugs are fine.

what heat range are your plugs?

'iriway 7' They are 1 level colder than stock. They are gapped at 0.76mm

I had the same problem with my Avenir. Later found out the spark plug tip blew off and ended up blowing my 2nd cylinder piston. I don't know what to tell you. Maybe try some NGK7es11's or something, I used those and they work(ed) great

Pull the plugs, check the tips to see if theyre soaked in oil
Then do a compression check just to be on the safe side to make sure everything is good in the block

could be faulty/broken wire going to coil,transistor, etc....