whenever i step on the gas in a high gear like 3rd or 4th even 5th below 2,000 rpms it backfires like crazy then starts missin. sometimes it'll just do it on its own then it lose all power and i'll have to pull over and it'll idle really rough and sound like its missin. then i put my hand over the tail pip and its spittin exhaust in sputters like its misssin but sometimes after idleing for a while it'll correct itself and run fine. i have no clue what it could be anymore.

 

Maybe the coil pack,wires or plugs. Check the connection to the coil pack 1st. If it constantly runs rough, it may be the timing belt has slipped on the gear. Hopefully it is just the coil pack.

 

Did you check the fuel system?

 

im positive its not the coil ive swapped around a few of those but not really plugs or wires would bad plugs or wires cause that only sometimes tho cuz it wont always do it. i have not checked the fuel system other than the time i hada replace the pump. i had 4 psi to the rail and somehow it was still barley running. i went to the junkyard and got one off a 126,000mi neon and it worked for me and i had 49 psi to the rail. i put noid lights on the injector plugs and those were pulsin when they should but would my fuel pump just decide to get weak out of nowhere by stepping on the gas? i thought fuel pumps either worked good or not at all, no in between but idk could it just be weak at times?

 

yeah they can i had that happen in my old windstar that i had sometimes it would work great sometimes i could not even get faster that 45. so it is possible for a fuel pump to be inconsistent, however that might be caused by blockage in a fuel line or fuel filter too so.

 

well thats another thing none of the autoparts stores here have a fuel filter listing for a neon. and the thing mounted on the body says accumulator anyway. and the little clip thing on the assembly is the regulator/filter and no one has one. the only place i saw a regulator/filter is on modern but i dont need a 78psi regulator i just want a oem accumulator and regulator/filter so i know theres no restrcition

 

anyone know?

 

I just went through a similar experence with my 96 SOHC. My engine is re-built with a crane cam, cam gear, head work, etc. I was running the Mopar PCM. I went through all the problems that you have stated. Backfire, popping through the intake, missing etc. It never did throw a code though. After allot of trouble shooting at my friends shop with his snap-on scanner, a volt meter and a dwell meter we came to the conclusion that it was the PCM not sending an adequate signal to the right side of the coil pack. We diagnosed this problem for about 2 hours, testing everything from compression, leak down test, voltage per wire at the terminal and at the plug. Crankshaft positioning sensor and the camshaft positioning sensor. We even checked the continuity in the wiring harness from the PCM to the coil pack..my friend is very **** and thorough about this kind of thing....lololol----but all checked out. First thing we thought it might have been was the timing. It almost sounds like it might be advanced to far and backfiring when the pedal is smashed. My problem though was definitely the PCM....we put the factory one back in and everything is running smooth. Now I'm looking for another Performance PCM. Maybe this will help..........Good Luck

 

I'd double check the timing ... sounds like it jumped a few teeth

 

well i plugged in my stock computer and tried that too but same problem still occurs. and i just replaced my water pump and timing belt too and timing marks are perfect