I have an intermitent miss that is driving me crazy, as well as, poor fuel economy(12-13MPG Hwy). Sometimes it backfires thru the intake, surges @ a steady cruise, stalls when coming to stop, spark knocks(not all the times), falls on its face when pulling away from light, etc. I have checked the timing(10btdc), codes(none), tried running on either tank, cleaned throttle body & iac, changed computer. I don't know what to do next. HELP!

 

Maybe its the o2 sensor

 

Try cleaning your O2 and your TPS...also check the routing of your number 7 and 8 spark plug wires.....sometimes when they get too close they'll cross on each other....check for bad/cracked plugs too...or bad plug wire connections...may even be a faulty coil......Luck

JR

 

Assuming that all the other items are functioning, build a restrictor plate out of some metal stock (16-18 gauge) and install inbetween the EGR and the manifold. Reduce the holes to 3/8" diameter and that should take care of it. Very common problem with the I-300 cid's when fuel was chnged to blended methanol!

 

What Flareside said, X2. And, look here.



Your symptoms are very familiar.

 

Thank you for your suggestions. I will look into each when I get 2 minutes to string together.

 

I replaced the cap, rotor, plugs, coil & re-routed spark plugs wires (FMS wires less than 8 mos old). Runs better, but intermittent miss is still present. Need help, please. The guys that I work w/ want to put a SBC in it, I want to keep it all Ford.

 

My EGR valve has the metal hose on the bottom & the 2 bolt flange on side, where would this restrictor plate go? I think I know but want to make sure.

 

Where it bolts to the manifold.

 

Thanks, I give that a try.

 

Hey Brett....I'd like to see some pics of your ride dude...sounds like it looks pretty sweet.....

JR

 

It is a work in progress. I have been meaning to post some pictures of my truck in my gallery, I jsut haven't had time with work, remodeling house, life in general, but I am going to try to get it done soon. Thanks.