Pontiac Sunfire won't run... running out of solutions?

[Melody]

My Sunfire won't run right. It has a really rough idle, wants to stall out while driving, sometimes has very little power. Today it stalled out while driving down the road and wouldn't restart. It's not the battery (I had all other power working in the car) and it's not the starter (the vehicle turns over, but won't actually start).

My check engine light has been on...even after changing the spark plugs, spark plug wires and the fuel filter. When we hooked it up to a hand-held engine thing to test for the cause of the light, it stated multiple cylinder misfire. Does anyone know what could possibly be wrong with this vehicle?? I don't want to be in the blind when I take it to a garage and get charged an arm and a leg for it.
I probably should mention that the car is a 1996 with 154,000 miles on it. I know, it's old w/ high mileage.. I should expect problems. I would just rather have it fixed versus getting into a 6 year loan w/ the way this economy is going.
My boyfriend changed the fuel filter already (he has changed many, many of them in the past) and a mechanic did my spark plugs and wires last week. I didn't have him check anything else, I just sent it in for new plugs and wires...so I know they are gapped correctly.

 

[vincentmb615]

check fuel filter, you probably didnt gap the spark plugs right, also check the distrubutor cap and inner rotor on it, engine misfire may mean your head gasket is leaking there is various reasons for it but deff double check your tune up

 

[kevusaborn]

When was the last time you had a timing belt done ?
There are a lot of things this could be but it could very well
be that the timing belt has jumped out of position and is about
to break. jumped a tooth as they call it..

I hope things work out at the repair station for the better..

Good Luck to you.

 

[Gobyknows]

Multiple cylinder misfire means that some or all of your spark plugs are not firing when they should. This condition continues after you have replaced the wires and plugs indicates a deeper problem. Your distributor could be tracking. By replacing the distributor cap along with the rotor, you will solve that problem ...if that's whats wrong with it. I would suggest that you have the air filter changed. A clogged air filter will cause jumpy behavior.

The trouble codes need to be cleared from your computer after every part replacement. Your hand held code reader should have a clearing function. There are so many things that can cause the symptoms you are experiencing. Your mass airflow sensor could be dirty, your throttle position sensor could be failing. Your camshaft position sensor or your crankshaft position sensor could be failing as well. Was the code you got about the multiple cylinder misfire the only code you had?

Your computer may need to be rebooted. You can disconnect the battery for 4 or 5 hours and then reconnect it. This will clear old trouble codes and maybe give you a fresh start. I would try the air filter first. Then the distributor cap and rotor. I hope this helps you.