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Misfires and a/c causing loss of power when idle

my 1998 hyundai accent has #1 & #4 misfiring. iv’e tried the plugs, wires, and the ignition coil. misfire is still there. now that it’s ,(finally), hot out, i’ve turned on the a/c. funny thing happens then… when at an idle the a/c drains power from the engine. it has even stalled out on me once. i checked out the alternator. it’s fine. now it idles rough and doesn’t accelerate as smoothly as it did. could the misfires and the loss of power be connected? if they are different, what could they be?

really? no one wants to touch this one?

Not all misfires are ignition related.

Has the fuel filter ever been replaced? Are you sure the fuel pressure is OK and the injectors are operating correctly? You could swap the injectors from #2 and #3 with #1 and #4 and see if the misfire moves with the injectors.

Not sure what you mean by “drains power from the engine.” The AC does, indeed, rob power from the engine, but you seem to be talking about electrical power. Can you clarify?

i’m talking power as in accelerating. it sputters then goes. never did that until i turned the a/c on. now it does it regardless of the a/c being on or not. it feels like it wants to stall. i wouldn’t know anything about swapping injector, (i’m just a layman), but the fuel filter has occurred to me. anyways, thanks for the info!

oh, btw… if i can fix the misfire than my little gremlin can pass emissions. i do like getting 36 to the gallon!

Swapping the fuel injectors around is a troubleshooting strategy, to save you money on parts. If the misfire(s) move, that fuel injector(s) is faulty. A garage won’t do it for you. A local lad (novice mechanic) could do it. He could, also, change that antique fuel filter. After 50,000 miles, a fuel filter can start causing problems.

Does this have a distributor? Ignition module? Have the valves been adjusted? Get a compression test.

i changed the ignition coil, as mentioned in the original post. loss of compression would mean loss of performance right? it drives just fine on the highway. city driving on the other hand… as for the valves, i haven’t touched them.

i know just the person who will help my swap the injectors. and i’m pretty sure i can change the filter myself. thanks for the help.

Low compression on #1 and #4 could give the symptoms you’re seeing.

If the valvetrain is the type that needs periodic adjustment [check the owners’ manual] and you’ve gone over 60-90K miles you might have tight valves. A compression test would show this.

Since #1 and #4 aren’t adjacent I doubt it’s a head gasket issue.
Have you changed the distributor cap and rotor?

like i said. i have changed the ignition coil. there is not a distributor on my car. i thought the coil was the culprit because #1 & #4 are on the same side of the coil pack.

“like i said. i have changed the ignition coil.”

To most car people that means one coil. A coil pack is plural: coils.

“there is not a distributor on my car.”

I asked this back at 08/17/2009 3:55:14 PM, but got no answer, so I went with what info I had.