I have a 2004 coupe just did wires and plugs Bc the car had a mis and was throwing multiple misfire codes, The misfire codes are gone but now it’s back firing thru the mass airflow I can here what sounds like a pop that’s happening here and there. Also the car is running rough and trying to stall out the rpms are under 500 rpms. Can’t figure this out help. I did new wires new plugs, replace fuel filter, some vacuum hoses, new mass air flow. And also the exhaust is getting really hot fast I’m thinking maybe clogged cats?

Steve thanks for the reply. None of the wires are crossed, believe me that’s the first thing I checked. The MAF is brand new, I wanted to eliminate that right away so I replaced it. The vacuum lines are all secured and on. The car has 120k on it I’m wondering if the cats are clogged because it kinda seems like a exhaust backfire, and it’s only happening when the rpms drop really low, why I think that is because the exhaust is getting hot fast which doesn’t seem right to me. I was trying to find a post about anyone having a misfire with bad cats but couldn’t. So as of right now I have a misfire, no codes, rough idle to the point it stalls out or try’s too, I don’t know if that backfiring is happening because the car wants to stall or what, but I am gonna try to run a scan to see what all the sensors are telling me.

I replaced the housing not just the sensor, if that’s the housing ur talking about? The pcm I pulled when I first got the car which was in December and redid the solder just in case Bc when I bought the car the skreem module was bad and didn’t know what it was at first. I got a good deal on the car Bc of the skreem and the prior owner didn’t know what was wrong with it. It was a dream car for my mom so I purchased it for her to repay her for all the years of hell I put her thru .

Thank you for helping Steve figured it out!! Wait until you here this.

Thanks for your help but figured it out today as I started digging into it further. Lets just say if ur not mechanic don’t try to fix car related issues. So I did a soap and water test the other day to see for vacuum leaks and replace hoses and I noticed some silicone which I thought was silicone and heard a bad intake leak, so I replaced the map sensor today and started moving somethings to realize that so called silicone was actually jb weld and there a huge hole patched on the intake manifold actually cracks all over the intake manifold. The mis I thought I had was actually a real bad intake leak causing to much air to be sucked and causing a mis and bad fire. Someone did great mechanic work!!! Off to find a intake. Will post pictures of the intake when I pull it out.

Will post pics when I pull it out the hole is 4in x 4in hole, patching isn’t gonna help. I found one for 175.00 used just have to have it shipped.

Flex seal lol

https://cimg8.ibsrv.net/gimg/www.cro...74ba585f1.jpegHere is the notorious jb weld intake manifold thanks again guys for your in put and help, I have to rebuild the injectors and then I will let you guys know how it runs.

I know lol as you can tell.

Steve it’s all back together runs better then ever. Someone’s gonna be a happy camper just in time for summer.