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Could the o2 sensor make it run rich and miss? Mine was getting really bad fuel economy and I read on here that the o2 sensor should be the first thing to change. I disconnected the old one and started the car and went for a drive and it runs exactly the same....so im guessing it was cactus. Havnt had a chance to drive it yet with the new sensor.

o2 sensor has nothing to do with the on load fueling only around town. It is possible it is the cause of poor fuel economy though. Get a consult cable and find out what sensors have failed.

Actually an air leak will make the car run rich hence rich misfire, it will also cause bad fuel economy.

boost gauge goes to 7 psi max. dont go over that. holds boost too...

The gauge isn't in psi, it is in mm of mercury. What does it read in that?

If it is 7x10mmHg it is 14psi which absolutely explains the misfire.

Edited by Rolls

i manually fitted a boost gauge so i could see what boost i was running, i achieved 7 by doin the high boost mod form the to do section on here, and that made it 7 psi, i thought that could have been the problem so i reversed what i did today ,and it still does the same

ok.....so it seemed like the problem went away but it is now back...

I tried changing the plugs out too some .8 gapped copper plugs but it is still there.

I have found that the problem is worse when going around big sweeping corners or up hills...weird..

Ive also noticed it isnt only up high in the rev range but also down low...like the moment I jump on the trottle it starts to cut...

Next step is to re solder the AFM and clean with contact cleaner

Any ideas what else I should try?

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