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Stuck valve?? Exhaust is pulling backwards

4006 Views 16 Replies 6 Participants Last post by  Chief2Horses
What all makes the exhaust suck backwards.

I have no exhaust leaks. Im figuring a stuck valve, but which side intake/exhaust?

Compression test was bad, but could it be anything else. All cylinders pumped up about the same.
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Compression ring wouldn't do that would it?

Im not worried about which valve really, just got a valve job on spare heads and all new top end valve train is gettin put on.
Im do a compression test again. With a different gauge.
Well, I ripped the heads off and replaced the entire valve train with all new parts. Rebuilt/surfaced heads, new springs, lifters and everything. It doesn't pull the dollar bill backwards anymore but still runs rich. Still same gas mileage.

I replaced MAF(runs 5% better) with junkyard one 2 days ago. Seems not as rich now. New CAI also, EBAY $40!!! My exhaust is "tinging" now from where its getting hotter(leaner) and the smell doesn't run you out of the garage as quick. Also warms up faster.

I think the MAF was makin it run rich tho. I thought it was a bent/burnt valve or spring or something as well, with it suckin a dollar backwards it would have had to been, but it --is-- possible for this to happen and it run ok, im pretty sure, idk. I bet a lot of cars a dollar bill will pull backwards and be fine. I wanted to make sure a valve train component wasnt the culprit tho. I watched while the mechanic drove it while the Scan tool was plugged in and the MAF was movin around so I skipped it. He said it looked good too.

Im gettin a new MAF just to see what it will do. Im gonna fill up gas tank and see what the junkyard MAF -MPG- gets me compared to the new, out of the box one.
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Brand new. Bosch. They read fine(scan tool) before I replaced them as well.

It just runs like it takes too much effort. Trans shifts way too soon and won't downshift like its supposed to. Idk anymore. Its for sale, lol!!! Low miles, swapped heads with no wrist pins knockin!! Sounds mean, runs real good with your foot half way in the pedal. The car is very quick don't get me wrong, 110mph in second gear. Just auto trans and those air plane gears are killin me!!

I'll see what this next full tank gets me. Mite be solved-MAF. Ill post with results soon!!:bigthumbsup
Lol, Ive done everything!! Just about every sensor already replaced. I replaced all vacuum lines with rubber hose. I even did a smoke test(push smoke thru engine to check for leaks.)

No MIL either. Once it came up with a fuel pump somethin but it only showed up once. Open circuit/ground or somethin like that. Prob a false code I was told by the mechanic since it doesn't show up in every scan.

All new igntion components, new press regulator. Timing at 14* base. It runs good, just won't putt around.
New VSS lol. Shifts premature. There is no adjustment on AODE trans right? Just a throttle cable and cruise control is only cables up there. 95' GT conv.
Im thinkin chip too. I want one written for it tho:)
Mass Air Flow MAF got it runnin right. Not the junkyard one that I wasted money on. I swaped with a used one and still ran wrong for me. So I got a new NAPA one. Sounds and runs totally different. Getting in and out of gas pedal, recovering momentum, letting off pedal. Much better now. Sounds good too. I probed MAF and it was within ranges. Maybe just lazy or not so far out.. Idk?? Ford Junk!!!!!!!!!!!:shigrin Ill report back with MPG increases to see if this car has fooled me once more.
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