Misfire, low idle and low voltage oh my!

[calliph]

I have a 2001 firebird. My car constantly runs rough due to misfire. It runs Worse uphill and smoother down hill. When I'm at stop lights my voltage drops and fluctuates and the car comes close to cutting off (lights and gauges dim at night). I replaced plugs and wires to no avail. I then took it to autozone and they say it's a cylinder 5 misfire. I'm not sure what to do. I'm thinking altenator and ignition coil but not sure. Could it be fuel related?

[Need4Camaro]

Re: Misfire, low idle and low voltage oh my!

I doubt its fuel related - your lights wouldn't go out if your car wasn't receiving enough fuel because even if the car completely died, your battery would keep all of your lights working. You might have a loose ground. Check to make sure no corrosion around battery. Alternator probably could cause that too but from my experience an Alternator either worked or it didn't but I won't rule it out.

The coil packs are only $20 a piece and if you haven't already replaced them then now wouldn't be a bad time to do so.

[firebird19_99]

Re: Misfire, low idle and low voltage oh my!

where did you buy your coil packs for $20 what brand?

[calliph]

Re: Misfire, low idle and low voltage oh my!

Thanks, I will try the coils first and see what happens.

[Pewter02Camaro]

Re: Misfire, low idle and low voltage oh my!

Dont throw parts at the problem, if you really want to trouble shoot the issue the right way, mark each coil pack. Then swap locations so that the one that is for cyl number 5 is in adifferent location. Then see if the misfire follows the coil pack to a different cyl. If you do this and it stays on cyl 5 my next step would be to look at the coil tray module that is under the coils. The alternator only operates above a certain RPM so if our RPM dips due to the misfire and drops below that threshold you alternator turns off. That is the dimming you are seeing. Bottom line fix the misfire first then go from there.

[Fin]

Re: Misfire, low idle and low voltage oh my!

Sounds like a bad coil. You can take a spray bottle with some water and spray it on the coil while the car is running. If the car runs worse as you do this, you have a bad coil. I'm sure there are other ways to test for a bad coil, besides that. As far as the other issue, sounds like your alternator is going out. Take it to a local automotive parts store and get them to test it.

[CFreed11]

Re: Misfire, low idle and low voltage oh my!

I'm just throwing this out there too, I had a rough idle and intermittent misfire. Turned out it was actually a defective AutoZone plug wire. When I went to check the plugs, one wire literally snapped about 3 inches above the plug boot.

[calliph]

Re: Misfire, low idle and low voltage oh my!

Thanks for the help. I had surgery on my right hand which made it a tough one hand job (which I put off until last weekend) lol. I swapped the coils around and that's what it turned out to be. I replaced 2 of the 3 last summer and thought the 3rd was fine I guess not lol.

I still have slight voltage drops and a loud ticking noise but she runs like a champ now. I guess there is more work ahead

[Fin]

Re: Misfire, low idle and low voltage oh my!

Go get your alternator tested. The regulator inside your alternator may be on the way out. As far as the ticking sound, do you have headers or the stock manifolds? If it doesn't sound mechanical, it could be a leaky header or exhaust manifold. You can get a mechanics stethoscope and listen to various places around the engine compartment with the engine running to isolate the noise. I hear a flexible piece of rubber hose works, too.

[calliph]

Re: Misfire, low idle and low voltage oh my!

I'm pretty sure I have an exhaust leak but the ticking noise is louder than previously. So I'm not sure if it's bigger or something else new, but once it's running for some time the noise is gone. I've been planning to get pacesetters and a stock t/a dual exhaust when I get a chance to.
It almost sounds like it did when the egr was off (sea foam cleansing)