mstahoo

Not sure on the fuel filter......I had it dynoed a while back and he did say it ran a smidge lean but, not enough to be problematic....it does have an inline fuel guage and high flow pump, and yes a regulator....so maybe fuel filter needs looking at. I cleaned the MAF and IAC a wile ago and things improved but, someone said if the MAF is acting up(its a Granatteli-24lb) it could cause problems along the lines Im having.....
Im gonna look at the things we talked about and get back to you. Thanks again for your input. In the mean time if you think of anything else.....let me know. I check this thing daily.

mjr46

pull them damn iridium POS shat ball plugs out.........are you running a vtec or a jap car?? I didn't think so, the 5.0 tfi system was not designed for such, standard copper core resistor plug is all you need, good chance that'll solve the prob

mstahoo

I may do that last but, the car didnt do this before, WITH these plugs..... Also I noticed a small vacuum line was disconnected from the fuel pressure regulator. I plugged it back in and drove for 5 minutes, didnt seem to do anything but that might have been causing the fuel pressure to change incorrectly at WOT....?????

mstahoo

??..... ALSO!. lol, It got cold over night here(Im in South Florida) so cold means 60 degrees. And the car runs better of coarse in the cold BUT, the misfiring didnt happen so much(or alot less) when it got cold out. TIMING MAYBE?? cause cold air makes the computer advance timing, and if it ran cleaner with the timing advancing alittle?......

eh.....eh!?.....am I on to somethin?....

dawson1112

cold also causes ecm to richen the mix

FrostByte

60f cold, lol. that wont do it. I know the Cubans/hispanics ther wont work below 70F, but not a car, lol

mstahoo

So the richer mix is also making a difference?...hmmmmm.... I may need a re-tune on this thing. I baught it like this(with all the mods) but the guy put it all together like 5 years ago, and it was a weekend car for 4 out of the last 5 years.
Ill probably change the fuel filter, since thats one thing I havent done, and maybe the spark plugs are 5 years old and need to come out of there. They are NGK Iridium, some folks on here think I sould pur some copper autolites in there, what do you guys think?...

FrostByte

Sorry I dont mean to LOL @ you but its 26F here right now & it wouldnt make a diff on how well the car runs except to have about 30 more hp than @ 70F. They LOVE the cool air.

Have a pro that knows stangs take a look @ it.

mjr46

wrong again.........I run a 89 with every bolt on you can think of and a t -trim with 12 psi all on stock ecm and no tune and it runs excellent, a tune will only cover up underlying probs, run a koer test/cyl balance test

mstahoo

@Frostbyte, no offense taken on the "lol", I get that alot about the temps here in S. Florida. BTW, the humidity is 100% today! Saw it on the news this morning. @mjr46, Damn am I wrong that much? lol, . Im embaressed to say I cant seem to do the KOER test properly......ok go ahead and grill me. lol