Engine misfire? *UPDATE*

[07GtS197]

Good luck getting a new screen, sct doesn’t support the x3 anymore.

I hope it is the cam sensor but I’m not totally convinced but depending on the mode of failure it’s possible. Unplug the sensor and take a short drive on a deserted road. It’ll run on waste spark but it will run.

 

[thatsnninety5]

Cam sensor replaced, crank sensor replaced, it still does it, ill crank it over and itll do fine until I get to a stop sign, then itll start to do it again and now its to the point where it barely can go 10ft without it sputterings and backfiring and misfiring like crazy, now if I step on it, itll go through with it and drive normally, fuel pump primes, I dont hear any whining from the fuel pump while at idle or driving. Still havent tested the fuel pressure but i am going to test spark in each cylinder by taking out the fuel pump fuse and taking out each boot with a spark plug on it and crank it to see if i have a clean crisp spark

 

[07GtS197]

If it was spark it would be worse the higher the rpm’s get. Any codes? At this point we’re only spitballing. If it’s only at part throttle I’d look at the o2 sensors like John suggested if there is water in the connectors, maf and tps. Wet or failing cops will do ok at idle but will cause misfires when stepping on the gas but it wouldn’t clear up at higher rpm’s.

 

[thatsnninety5]

If it was spark it would be worse the higher the rpm’s get. Any codes? At this point we’re only spitballing. If it’s only at part throttle I’d look at the o2 sensors like John suggested if there is water in the connectors, maf and tps. Wet or failing cops will do ok at idle but will cause misfires when stepping on the gas but it wouldn’t clear up at higher rpm’s.

The only code im getting is that p0320, I just check the o2s and maf. None of them are wet and theyre plugged in all the way and the wiring on them is good. The car seems to be okay at idle but when im driving like i said it is good and will sputter here and there but once I come to a complete stop and try to go from said stop, it will sputter and misfire and backfire and then if I punch it, it essentially stops the misfiring and stuff

 

[ttocs]

any chance you got some coolant in the motor/trans harness that is around the pass firewall IIRC? It is supposed to be sealed and immune to things like this but if it did leak and some got it you might have some corrosion in there now that is causing just enough resistance to cause a problem. Take it apart and inspect the connections, clean with a wire brush/contact cleaner if needed.

 

[96blak54]

You are saying any part throttle the car runs like crap(missing,stumbling) but when punching full throttle the missing stumbling goes away and runs good?

That is not a spark issue, nor a fuel pump issue, not a crank or cam sensor issue either. That dang P0320 tho......Hmmmmm

 

[thatsnninety5]

any chance you got some coolant in the motor/trans harness that is around the pass firewall IIRC? It is supposed to be sealed and immune to things like this but if it did leak and some got it you might have some corrosion in there now that is causing just enough resistance to cause a problem. Take it apart and inspect the connections, clean with a wire brush/contact cleaner if needed.

There could be I will take a look see what I can find

 

[thatsnninety5]

You are saying any part throttle the car runs like crap(missing,stumbling) but when punching full throttle the missing stumbling goes away and runs good?

That is not a spark issue, nor a fuel pump issue, not a crank or cam sensor issue either. That dang P0320 tho......Hmmmmm

Yeah exactly, it is very weird. Ive never had anything like this happen and its frustrating spending money on sensors when they arent the problem, now lets go back to the beginning of this thread, is there something i couldve done pulling my dash out for my heater core that could cause what is going on?

 

[RAU03MACH]

like i say check all connectors

 

[07GtS197]

Did you damage any vacuum lines?

 

[thatsnninety5]

Did you damage any vacuum lines?

All the connections seem to be nice and tightly plugged in, I know there is those vacuum connections behind my glove box, they are plugged in and tight. Is it possible I could pinched those somehow putting my dash back in?

 

[thatsnninety5]

Just took it for a test drive, came to a stop at a stop sign and it stalled, put it in neutral and crank it, then it died instantly, continued to try to do this about 5 or 6 times and it just kept happening, so I ended up just pushing it into the lot next to me, I put it in park and im sitting here, I cranked and it dies instantly, before this test drive I tested my spark and all seemed good but there was white “powder” on the spark plug ends, im not sure what would cause that.

 

[ttocs]

almost sounds like fuel. To test this, prime the pump 2x. Turn the key on, count to five, then turn the key off and then back on and again count to 5. This time at 5 start the car and see if the additional priming made a little more pressure and if it lasts longer

 

[thatsnninety5]

almost sounds like fuel. To test this, prime the pump 2x. Turn the key on, count to five, then turn the key off and then back on and again count to 5. This time at 5 start the car and see if the additional priming made a little more pressure and if it lasts longer

I just did that and it still shuts right now, I also tried priming it about 5 times after I did what you said and it starts then shuts right off. I also have a code for a bank being to lean. The guy I bought it off of, I ran into him about 4 days ago and he just asked me how the car was and I explained to him the issues and he said when things get changed like spark plugs I need to make sure the tune of it is right, that flash tuner I mentioned before has the tunes on it, a street, a track and a drag, but the screen on it is broken and I wanted to get a new one so I could see if the tuning thing was the problem but unfortunately I cannot

 

[95opal]

I just did that and it still shuts right now, I also tried priming it about 5 times after I did what you said and it starts then shuts right off. I also have a code for a bank being to lean. The guy I bought it off of, I ran into him about 4 days ago and he just asked me how the car was and I explained to him the issues and he said when things get changed like spark plugs I need to make sure the tune of it is right, that flash tuner I mentioned before has the tunes on it, a street, a track and a drag, but the screen on it is broken and I wanted to get a new one so I could see if the tuning thing was the problem but unfortunately I cannyou have a code for an entire

I just did that and it still shuts right now, I also tried priming it about 5 times after I did what you said and it starts then shuts right off. I also have a code for a bank being to lean. The guy I bought it off of, I ran into him about 4 days ago and he just asked me how the car was and I explained to him the issues and he said when things get changed like spark plugs I need to make sure the tune of it is right, that flash tuner I mentioned before has the tunes on it, a street, a track and a drag, but the screen on it is broken and I wanted to get a new one so I could see if the tuning thing was the problem but unfortunately I cannot

You have a lean code for an entire bank? I assume this is a 98 and under car? If so that banks coil pack is shot. Pull the plugs on that bank and you will find they are fouled and soaked.

 

[thatsnninety5]

You have a lean code for an entire bank? I assume this is a 98 and under car? If so that banks coil pack is shot. Pull the plugs on that bank and you will find they are fouled and soaked.

The code is lean for the entire bank, the reason I bring up the tuner is because when I use to be open headers, when I put my exhaust on with no cat and mufflers, lean code popped up. This is a 98’ and my plugs are okay, just changed the spark plugs last week to see if it would help my issue but it didnt and the boots were in good shape.

 

[lwarrior1016]

Lean codes when open headers is from fresh air on the oxygen sensors. You need like 24” of exhaust after the sensor so it doesn’t lean out from fresh air.

You don’t change a tune when you change spark plugs. You don’t even change a tune when you change sensors. The only thing that might need a tune is if you get bigger items like injectors or mas airflow sensor. That is only if you deviate from stock spec

 

[07GtS197]

You have to check fuel pressure to rule out the fuel system.

 

[95opal]

new crank position sensor and 8 new spark plugs (my old ones were all black on the ends)

So old plugs were fouled now new plugs in for a week. You should really you pull a plug on the lean bank to look at it. Without knowing the specific code it could mean the o m is at it's lean adaptive. Basically it can't lean out the rich state enough it's past its adaptive limit. It's worth a 10 second look.

 

[thatsnninety5]

So my car has been in the shop the past 3 days, it seems like the issue was way worse than I even thought and I want your guys opinion, so the shop said it is my PCM with my crank sensor. They said they cant fix it because they just dont have the software for older cars like this, they only have stuff for the newer 5.0 and coyotes. Now all the other shops I am calling are saying they could just replace the PCM but it would obviously cost me an arm and a leg, now do yall think itd be best to set my car aside, find a PCM and replace it, or let a shop do it, or continue the search for a shop that has the software to be able to fix my PCM. This one has really stumped me. Out of all the issues ive posted about on this forum, this one is the real kick in the ass.