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MSJHWT
03-03-2005, 05:07 PM
Okay, I've been having some 'surging' issues, at higher RPMs, in 2nd and 3rd gear, the car will go-stop-go-stop-go-stop. Took it in to the dealership, and the guy who was cool about mods is there no longer.
Was told it threw a misfire code, and that to diagnose it it would have to be returned to factory -- didn't feel like fighting it.
So looking for common misfire causes, I'm thinking bad plugs/wires? I also think my MAF may be acting up, and I'm getting one from a member on here just waiting on it.
Anything else I should check for the cause of the misfires??

Infernall
03-03-2005, 09:35 PM
My 2001 SE did this when my fuel filter was very clogged. Happened between speeds of 60 to 100 KM/h or so.

Fuel filter was apparently causing the engine to run lean, thus starving the engine of fuel.
I was also throwing a misfire code, and the dealership wanted to replace the O2 sensor ($$$) before they simply checked the fuel filter and found the real problem.

In the end, O2 sensor was just fine, but I needed a fuel filter. Problem has not returned, and it has been about 6 months.

GAGTSCTGuy
03-04-2005, 03:29 AM
Returned to the factory? That is crazy talk! (oh yeah, they might not like that little bottle you've got hooked up) And hey, didn't they just close the factory or are about too, but anyways. What code was through? Just a general misfire code or were there more. Find out the codes and post them and maybe you can get some more help. Like Infernall said have you replaced everything, fuel filter, plugs, wires, o2 sensor, all that good stuff, not sure how old your car is (mileage/age wise) but you might want to check those things out.

Also didn't you just get the first PCM program from DHP for a SE, or was it a custom? regardless, You may want to take a scan dump (I'm not sure what people use most the time, but they end up in excell spreadsheets) and send it off to charles, maybe something is not right with the re-program.

edit: You should have left me know about the MAF, I could have possibly rode over one weekend and let you test it with mine, atleast I think an '04 would work in an '02, wouldn't it?

iceman
03-04-2005, 03:51 AM
It's illegal for them to deny you service solely because of the presence of aftermarket equipment; the burden is on the dealer to prove any malfunction is caused by aftermarket equipment NOT assume the problem is caused by its presence. Go read up on the magnuson-moss act.

Anyways - fuel filter, injectors, plugs, wires, coil packs, etc... could be anything. Was the code reporting a specific cylinder? If so start there.

Panacea
03-04-2005, 09:35 AM
Yeah, clogged fuel injectors was causing a missfire on mine.

elim
03-04-2005, 09:37 AM
I had the same hesitation, surging, that you describe. It would get to third for me, then it wouldn't shift into over-drive, it would just get up to the correct RPM then shoot back down, and then keep doing it repeatedly. Turned out to be a bad TPS for me.

MSJHWT
03-04-2005, 03:42 PM
Thanks for the replies everyone.

Swapped plugs/wires today -- no go, next step is fuel filter tomorrow like Infernall first suggested I guess. I've never done one so going to have my girlfriends dad help me out on that one.

GAGT -- They've actually never seen the Zex kit haha ;) Everytime I go in there I take out the control, bottle and line so they've never seen it. Cars not that old milage wise, it shouldn't NEED the fuel filter, it's just 34xxx miles on it, but hey, going to do one anyway. D'oh, yeah shoulda said something to ya, but I got a pretty good deal on the MAF, $50 shipped, so it's not too bad.
As far as the DHP goes -- my PCM isn't working with the car. Been trying to just get a hold of someone at DHP has been a nightmare...I'm sure when its figured out it will be worth it....but using the stock PCM right now.

Ice -- I had a really cool guy at the dealership, but he left, and this new guys an ass :/ I figured I'd just let it go this time and try to solve it myself, if all else fails it will go back in there and they will fix it, and I made sure I didn't pay $97 for the code they pulled (walked out of there with a 0.00 balance ;) ) He didn't give me a specific code, just a message on my answering machine saying it had a "General Misfire Code in it's history", I think it's time I bite the bullet and buy a scan tool.

I'm going to hope it's not bad injectors, Pan, that dosen't sound like fun to replace, but if it's not the fuel filter I'm going to be going back in to the dealership first, I guess.

Elim -- I'm not really having a problem shifting into any drive, even overdrivel but not going to rule that one out, either. I've still got my old TPS-TEC laying around here somewhere, maybe I'll throw it back on and see if it does anything...

We'll see if the fuel filter does anything, I'll let ya'll know tomorrow...

Panacea
03-05-2005, 02:06 PM
Fuel filter needs to be replaced every 2 years or every 30,000 miles.

Also, like I said, clean your fuel injectors. Get some sea foam and feed some through the PCV valve.

Go to another dealer and have the code read. Mine told me what cylinder was misfiring and how many times it'd misfired.

MSJHWT
03-05-2005, 04:58 PM
Hmm really? I thought it was a 50k mile thing?
Well seems it needs replacing then anyway. We didn't do it today because my GFs dad had to work, we'll be doing it next weekend (as I don't drive the car during the week anyway). It dosen't seem that hard to do, and he got me the part for $11.50 from a friend at a parts store.
The injectors were "power cleaned" a while ago by the dealership. My dad got talked into it because I had "Performance Equipment" on the car at the dealership around 4k miles ago, cost him like $100 or something. Ah well, I didn't pay for it, but that should rule out the injectors. I'll update when the fuel fitlers in -- hasn't thrown another SES code yet, but I'm also not pushing the car hard when I drive (no flooring).

Panacea
03-05-2005, 05:01 PM
I had my injectors cleaned about 5-10,000 miles ago and they needed a good cleaning again. I took it to the dealer the first time because it was causing a misfire. Cost $100 and some change. Now I just use SeaFoam every oil change to clean out the injectors. Runs like new.

iceman
03-05-2005, 05:24 PM
Ah well, I didn't pay for it, but that should rule out the injectors.

No it doesn't, they can easily clog again in under 5k..

MSJHWT
03-13-2005, 04:48 PM
Well today I replaced the fuel filter and added Sea Foam to the gas tank....actually did it like 30 mins ago I still stink like gas after a 20 min long shower lol
I did it alone, and it was actually pretty frikin easy, I was surprised. I'm letting the car sit a bit just to make sure any gas that came out of the filter dosen't ignite on the bottom of my car because...yeah that would suck. So I'll update here in about a 1/2 hour.

MSJHWT
03-13-2005, 05:22 PM
Bah didn't help :(
Did the same thing, time to take it back to the dealership and bitch I guess :/

GAGTSCTGuy
03-13-2005, 06:39 PM
Did you check the coils too? And I was under the impression that changing the injectors wasn't that difficult, just costly.... What is happening now that you've changed the filter, still the surging issues, is it still only when you push the car hard?

You still under warrenty? If so, try another dealer if those guys are being jerks....

If not, remember that MD Mod day we were talking about, sounds like it might need to be a rebuild day... :(


Someone said something about the TPS, new TPS, GM PN: 17123852, $24.85. Might be something to check out

MSJHWT
03-13-2005, 07:34 PM
It actually got worse since I did the filter. I feel dumb, but it might be the Air Filter, I recharged it 1000 miles ago...but hey, simple things are normally the culprit eh?
Anyways I'm going to take it back to Anderson and just tell them I want it figured out, no ifs ands or buts next weekend. Going to school away stinks since I can't do anything to the car 5 of 7 days. I've got emissions coming up soon, too, so I need to figure this out :/

Edit: I'm going to try to take a video of it next weekend and upload it.

GAGTSCTGuy
03-13-2005, 07:53 PM
It actually got worse since I did the filter. I feel dumb, but it might be the Air Filter, I recharged it 1000 miles ago...but hey, simple things are normally the culprit eh?
Anyways I'm going to take it back to Anderson and just tell them I want it figured out, no ifs ands or buts next weekend. Going to school away stinks since I can't do anything to the car 5 of 7 days. I've got emissions coming up soon, too, so I need to figure this out :/

Edit: I'm going to try to take a video of it next weekend and upload it.

The air filter, that would be alittle strange, but who knows. It would have to be really dirty I would imagine. Well good luck at the dealership, let us know how it goes.

elim
03-13-2005, 07:54 PM
Someone said something about the TPS, new TPS, GM PN: 17123852, $24.85. Might be something to check out

:whistle:

geldartb
03-13-2005, 08:01 PM
my friends car did something like what you described in your first post turned out to be his coil packs

GAGTSCTGuy
03-13-2005, 08:13 PM
:whistle:

Sorry about that, I forgot who said it, and I didn't feel like reading the other posts to give credit, :boogie:

H.O. Driver
03-14-2005, 11:57 AM
Did you check your plugs? With the sauce and mods they should be gapped a bit less than stock, you might have fouled one up, or if they are the stock plugs they should be changed by now. The other possibility is the injector, my sister's 02 had the injectors flow matched by the dealer, less than 5k later the #5 one was clogged up again!

Hopefully your dealer will take care of you this time, just tell the guy to put the GM service manual down and walk away if he doesn't know how to work on cars and works for a dealer. lol

MSJHWT
03-15-2005, 03:04 PM
Plugs are AC Delco gapped to stock, I have a pair of Bosch gapped differently for nitrous runs, but took them out for the winter, these plugs have less than 5k miles on them :/
I think I'm just going to go bitch at them until they fix it :/
I really do hate going to school away/not having my car here, all this wasted time and then the weekend is so rushed.

MSJHWT
03-19-2005, 07:41 PM
Oooooooooooooookay, lets see where to start.

I replaced the air filter.
I replaced the MAF with the new one.
I went and cleaned some engine stuff.

Car runs fing amazing. I did some highway 40-80 runs, HOLY ****!
Car hasn't felt this good in a WHILE.

Only bad parts, it the idle now?
Idle does this:

1000RPMS, drops for 400 and almost stalls out.
Jumps back up to 1000RPMS like I put my foot on the gas, drops back down to 400. Repeat. Lights gets dim, it's like it's about to stall out. But as soon as I give it gas, Woooo hooooo!
Maybe Alternator?
Fuel Pump?
Something?

GAGTSCTGuy
03-20-2005, 06:59 AM
Oooooooooooooookay, lets see where to start.

I replaced the air filter.
I replaced the MAF with the new one.
I went and cleaned some engine stuff.

Car runs fing amazing. I did some highway 40-80 runs, HOLY ****!
Car hasn't felt this good in a WHILE.

Only bad parts, it the idle now?
Idle does this:

1000RPMS, drops for 400 and almost stalls out.
Jumps back up to 1000RPMS like I put my foot on the gas, drops back down to 400. Repeat. Lights gets dim, it's like it's about to stall out. But as soon as I give it gas, Woooo hooooo!
Maybe Alternator?
Fuel Pump?
Something?

Well I'm glad it is almost running, what did you clean up?

I doubt it is the alternator, maybe the fuel pump, did you clean the injectors? I guess you don't have a fuel pressure gauge, or a scan tool?

I would imagine if there is a problem with the fuel pump it might be causing the lights dimming, (motors take more energy to start than to run usually), I'm not a professional though. Just a guess considering how motors and stuff work.

If you have a volt-meter you can test the alternator, just keep an eye on it, it would be >13V. If you have a scan tool or fuel pressure gauge you could see if this is dropping or something (which would probably suggest a bad pump)

Hope something in this helped, keep us posted.

MSJHWT
03-20-2005, 01:39 PM
Yeah cleaned the injectors, no Fuel Pressure Gauge or Scan tool unfortunately :/
Let me go price fuel pumps from GMPartsDirect....well at least after this every maintance piece on the car will be good for a while haha :)
Actually just went to show it to my dad, and it was being wierd, idled at 1200 consistantly.

GAGTSCTGuy
03-20-2005, 01:49 PM
Yeah cleaned the injectors, no Fuel Pressure Gauge or Scan tool unfortunately :/
Let me go price fuel pumps from GMPartsDirect....well at least after this every maintance piece on the car will be good for a while haha :)
Actually just went to show it to my dad, and it was being wierd, idled at 1200 consistantly.

That is kind of high, mine idles at 600. I think the pump is around $170 but it says the level sensor is not included so I'm not sure if you have to transfer hardware or order another part number.... Are you planning to do this install yourself?

MSJHWT
03-20-2005, 02:04 PM
Well hopefully with the girlfriends dad, hes a mechanic so he knows his ish, he does his car, my gfs, her sisters and thier moms, but trying to get him avaible is kinda hard, but hopefully Friday or Saturday...

GAGTSCTGuy
03-20-2005, 02:26 PM
Well hopefully with the girlfriends dad, hes a mechanic so he knows his ish, he does his car, my gfs, her sisters and thier moms, but trying to get him avaible is kinda hard, but hopefully Friday or Saturday...

Cool, it doesn't seem difficult(Never done it myself though), but just seems like a PITA.

MSJHWT
03-24-2005, 09:45 AM
Okay....everyone laugh at me now. When I replaced the MAF and all...I didn't plug the IAT sensor back in, reason for my rough idle and SES light. Since fixing it, no SES light, normal idle, it *seems* all is right. We'll see how the track runs go :)

GAGTSCTGuy
03-24-2005, 09:49 AM
HAHA, there....


Are you going on the 1st?

MSJHWT
03-24-2005, 09:54 AM
Yes, I'm going this Sunday, and then going the first as well :)
EDIT: Running N/A on Sunday, and then I'll be running juiced on the first.

GAGTSCTGuy
03-24-2005, 09:58 AM
Awesome, I have yet to see a bottled GA, actually I haven't seen a fast GA at capitol yet, should be interesting. Mine and ravens are the fastest I've seen....

MSJHWT
03-24-2005, 10:04 AM
I've only seen two other GAs there out of all the times I've gone, Vintalage was one, I can't remember what he was running, but it was a baaaad day, humid and no traction at all for anyone on the track.
The only other GA I've seen there was a GT running 16.3s or so, dunno what was up with his car?
EDIT: Oh and 02Pontiac!, but he didn't run, he just came to watch my runs.
and one more EDIT: Hopefully I'll have my purge setup by then to come out from the hood scoops :)

GAGTSCTGuy
03-24-2005, 10:09 AM
I've only seen two other GAs there out of all the times I've gone, Vintalage was one, I can't remember what he was running, but it was a baaaad day, humid and no traction at all for anyone on the track.
The only other GA I've seen there was a GT running 16.3s or so, dunno what was up with his car?

I've seen a few running 16's, I was confused myself. They were impressed with mine (running low 15's :doh: ) and I only had CAI and Jet(And they are not suppose to knock .5-1 second off the 1/4.... Even in D with ETS on I ran 15.8, stock....)