runs like poo

[hac_gagt]

I have a 3100 V6 in a 94 grand am. Lately the car has no power, it hurks & jurks, like to stall, idles high, shifts really bad, give it alot of gas it just stumbles, let off a little and it accelerates better. When it goes when giving it lots of gas it is slow as hell. I have replaced: plugs, wires, air filter, PCV valve, fuel filter. Pleasa help.

[bszopi]

RE: runs like poo

Coil packs would be somewhere to start looking.

[SappySE107]

RE: runs like poo

Yup, that is what I would have guessed as well. Same issue I had when my coil packs were going to shit. Check your fuel pressure as well, as a fuel pump going south or a FPR thats broken can cause similar conditions.

[hac_gagt]

how do I chack the coil packs?

[corning_d3]

The easiest way to test the coil packs are to start the engine, and grasp the plug wire boot and pull it off the spark plug. You'll see fire flying from the plugwire to the plug. For the back 3 cylinders, you can pull the wire off the coil and test it the same way. I'm pretty sure autozone can test them, also.. Something else worth mentioning...have you checked the throttle position sensor?

[hac_gagt]

I haven't checked the TPS

[Juglenaut]

Another way is to check resitance of the primary/secondary side of the coil.

[series8217]

The easiest way to test the coil packs are to start the engine, and grasp the plug wire boot and pull it off the spark plug. You'll see fire flying from the plugwire to the plug. For the back 3 cylinders, you can pull the wire off the coil and test it the same way. I'm pretty sure autozone can test them, also.. Something else worth mentioning...have you checked the throttle position sensor?

Never do that with a DIS motor.

If the coils charge up but can't discharge (because there is no connection between the two terminals via the block, i.e. when you pull off a connector) you will almost certainly destroy the ignition module.
You can also hurt yourself.
Just take off a coil and check it as Juglenaut said. Resistance should be close to a known good coil. Obviously should be no shorts or open windings.

[Juglenaut]

I have only had a few bad ICM in my day.. I used the sparky test too only if I had a person to start and kill the engine. The sparky test works best on DOHC engines.

If the spark is trapt without a ground it will sink through the coil negative to ground on the primary side. NEVER pull plugs off at the coil while running.....

[corning_d3]

I meant pulling the wire away enough to get a good 30-35kv firing line (useful with a scope)