My car is running horrible under heavy throttle.

[melquiades]

mine is having the same problem after I washed the motor on saturday

[eDoog]

so I went to a GM mechanic today and he said it's most likely my wires. He told me if a coil was bad it would definitely throw a code. He said one of my wires could have a tiny hole in it causing the spark to arch to the exhaust manifold or the block grounding it out before it reaches the spark plug. He was telling me that this may be the reason why it 's not a consistent miss. Anyway, I am getting just my wires replaced on thursday and I'll tell you guys how it goes. Thanks for the advice though. oh, and for anyone who needs ignition coils, Autozone has them for $28.99 ea.

[mike h]

Originally posted by eDoog:
could have a tiny hole in it causing the spark to arch to the exhaust manifold or the block grounding it out before it reaches the spark plug

i think i have that too, its a white mark on the manifold where the wires rest right?

[eDoog]

I don't know about seeing a mark. I tried looking while it was dark to see if I could see any light but I didn't find anything. Hopefully it's just a faulty wire.

[Camaro2k]

Bad or faulty COIL will not throw a code (a dead one may). take off the rubber connectors and make sure they are clean (no visible corrosion or rusting on it). as long as you have proper length sockets and wrench you should be able to unscrew all 3 of em. not very hard to replace those buggers. make sure you route the cables properly.

plug combination

Motor:
6--5
4--3
2--1


coil packs:

1
4

5
2

3
6

[Speedin96]

replacing the coils is difinatly not hard at all

it's only 2 bolts per coil

and its like plug and play

just keep the wires in order like ^^ he said when mine did the EXACT same thing i replaced the wires/plugs and all 3 coils with MSD double tower coils. good stuff...

omg those coils were truly plug and play lol it was so easy

[Need4Camaro]

Also check your Alternator, seeing as though your belt fell of you might have damaged it...

[InsaneCamaro]

Try checking your fuel pressure if it just bogs under WOT and runs alright at half throttle or less. If you everything checks out on pressure and stuff then check the fuel pressure regulator, if u pull of the vaccume (sp?) and u feel wetness then change that. A junk wire will throw a code and flash the check engine light. It happened to me n flashed.

[Jtownrook99firebird]

Mine does the same thing. I think you have water in your gas. Try running some Heet or some alchohol and see if it goes away. Mine did but comes back everynow and then and I run some more... goes away. It MAY also be the coils.. if it was a wire it'd go in2 a dead miss and throw a code~mine has done that also. I haven't replaced my coils yet... but I most likely will just in case that has 2 do w/it also. A plugged cat... I doubt it~it'd prolly run hot b/c tha engine would be suffocating and tha rods would eventually go~I've been through that. I don't have one now by tha way [img]smile.gif[/img] Good Luck

[eDoog]

Well, I took my car to my mechanic and he inspected all of my wires and said they were fine. He then ran a full diagnostic and noticed that cylinders 2, 4 and 6 were running leaner than 1, 3 and 5. Well, on the way home my car FINALLY threw a code so I went to Autozone and had them scan it. Cylinder 5 was missing so I pretty sure it's probably a faulted plug. THe plugs have more than 50k miles on them so I'm going to change them (hopefully by myself if it's not too hard.)

Thanks for all the suggestions though. I'll know that when I replace my plugs and it still does this that my coils are bad or at least the one connected to #5.

Actually, should I replace the coil first or the plugs? If I should do coils first, can I just replace the one that's connected to #5 or should I do all 3?

[FunkZ]

Replace the plugs first. That coil fires 5 and 2 although it's possible only one side is bad. You can always swap two of the coils and see if the miss jumps cylinders.

[tdz16]

If your saying that cylinder number 5 is missing and threw the code, yet #2,4 and 6 are running leaner, that doesn't make sense. If you have a miss on a cylinder, its going to make that bank of cylinders run lean. Therefore 1,3,5 should be lean, not 2,4,6. I'd check that alternator. If its not getting your ignition full juice you could have problems. If not that, then look towards the fuel system. Hook up your multimeter to the battery while the car is running, see if you're getting 13-16 volts...if your only gettin around 12....get yourself an alternator. I hope this helps in some way.
~Tom

[eDoog]

No that helps a lot Tom but I thik Funk Z has a good idea of switching the coils. On and by the way, my mechanic said the passenger side cylinders are running lean but #5 has the miss (driver side bank). Couldn't it therefore be possible that it's the driver side that's running rich do to the missfire?

I know it's not the alternator, I just had it replaced 2 months ago (Bosch). It works great and I got it brand new.

[tdz16]

I need to say that when I said what I did, I was under the assumption that he is just using his scanner to watch the O2 voltages. If this IS the case, and there is a miss on cylinder number 5 (in drivers side bank), then that bank would run lean according to the O2 sensor. Think about it. You are measuring oxygen content with the O2 sensor, not fuel content. When you empty out a cylinder that hasn't fired through the exhaust, it now has a lot more oxygen than does a cylinder that just burned all of its oxygen during combustion. Therefore you end up with a "lean" condition where your miss is. If he is old school and reading the plugs to come to this conclusion, then your answer is right there, no guessing about it. Its a weird concept to understand as far as what I said earlier but if you think about it long enough, it makes sense. I know this isn't really helping with your problem but at least it takes away from the possible problems. Just keep workin at it and you'll figure it out.
~Tom

[eDoog]

haha, even if it didn't help, I still appreciate it. Anyway, It turns out it was the ignition coil after all. He checked the plugs and the wires and everything was fine so he popped a new coil in and it runs like new! Thanks for all of your help though.

-Casey