91 Grand Am Started Running Rough, Severe Lag, No Power

[hotcon67]

I Just Boutght A 91 Grand Am, And Within 3 Days, It Started Idling Really Rough, Won't Accellerate (0-60 In About 30 Or 40 Seconds),
And Shifts Hard. I've Been Told It Could Be The Ignition Coil Module, A Blown Head Gasket, A Bad O2 Sensor? But The Drop In Performance From Driving It Home (ran Smooth, Lots Of Pep) To Now Is Extremely Dramatic. It Has The Dohc 16 Valve Quad 4 Engine (not The Ho Though. Please Help! Any Suggestions, Advice Would Be Good. I'm A College Student, And Need To Keep It Running As Cheap As Possible.
Thanks, Everyone

[J-Ri]

Check the fuel pressure and condition of the ignition system.

Why was the head gasket given as a possibility? Was there coolant loss or smoke from the exhaust?

[Big-Z]

yes, collage, I get what you are saying! I am literally pulling my pontiac apart to fix some dinkie gasket. ummm, try the throttle position sensor (tps) how are the rpms wile ideling? I know that effects power.

it you dont have enough fuel pressure, it could effect ideling also

look for any leaks in any thing.

I really am wondering about the tps though, cuzz on my truck before, when it was not working, I jambed the pettal to the floor and it would just slowly putput up to speed. so check that. idk if it is adjustable or not, but you might want to have somone look at it, a friend, or maybe check with your collages automotive program if they have one, and maybe they could look at it for free (mine does that if the probelm is apart of what we are studying )

-Zack

[hotcon67]

Yeah. Checked the coils and module, both are good. It is pushing too much gas, as the exhaust pipe is wet, and the sparkplugs were wet with gas when we changed 'em. Still trying new stuff. Next step is checking the injectors and fuel pressure module (?), then possibly the catalytic converter? Hard to run a diagnostic scan though, because the freaking dummy light isn't on!! As far as the head gasket, I haven't checked it, as I haven't seen any leakage yet, but it does smoke when you start it and rev it. And it revs fine in park, but chokes to death in gear. I know you can pull the dipstick and see if there is gas in the oil, but it's at a friend's while he checks things out, so.... I will keep you all posted, and I appreciate the replies.

[yamahaiswitit]

Its not gas in the oil its Antifreeze, IF you dipstick is milky looking to to full Chances are you have a head gasket problem and they are not fun to change, I had to remove my whole engine in my 96 to fix it. Same problem Start good response in park once you put in in gear and hit gas Boggs for a sec then goes but Exactly takes a hour to get 60 mph, If there is not alot of collant in your oil ITs probably your intake gasket but if you get that far you might as well and change them all, Ebay the complete head gasket set for 70 with shipping.

[J-Ri]

Originally Posted by hotcon67

Yeah. Checked the coils and module, both are good. It is pushing too much gas, as the exhaust pipe is wet, and the sparkplugs were wet with gas when we changed 'em. Still trying new stuff. Next step is checking the injectors and fuel pressure module (?), then possibly the catalytic converter? Hard to run a diagnostic scan though, because the freaking dummy light isn't on!! As far as the head gasket, I haven't checked it, as I haven't seen any leakage yet, but it does smoke when you start it and rev it. And it revs fine in park, but chokes to death in gear. I know you can pull the dipstick and see if there is gas in the oil, but it's at a friend's while he checks things out, so.... I will keep you all posted, and I appreciate the replies.

It's probably not the catalytic converter, that wouldn't cause the unburned fuel. Did all the spark plugs have fuel on them? Check the Coolant Temp Sensor, if it's reading much lower than the actual temperature, the computer will increase the fuel. Also check the Intake Air Temp sensor, it will affect the fuel a bit, but not to the extent that yours is. Does it run bad all the time, or just cold, or just hot?

I can guarantee you that if there is coolant in the oil, it's not from the intake manifold. Inline engines don't have any coolant or oil passages in them. It could be a head gasket, but if the coolant is not low I wouldn't expect it, especially happening suddenly.