see thats what im thinking but im also thinking maybee something else is causing it like fuel delivery (but i changed fuel filter)or simple plugs and wires, but the exhaust sounds so muffled

 

yes when i drive it at lite throttle its ok but when i want to go i dont....but its worse now i have to give lite throttle to get up to speed but let off to shift up cause high rpm goes nowhere

 

thats definately clogged cat.

 

ok........its worse than i thought...........cat is fine.......so now what....the biggest difference i can see is the noise when i get on the throttle....it sounds like cold air intake u know that noise right? and its not beefy at all....and goes nowhere....a 4cyl would smoke me right now......

 

how was it you were able to find out if the cat was ok or not? if it is ok then replace the plugs and wires, pcv valve, air filter, o2 sensors, all the basic tune up stuff and get a $5 can of seafoam and pour in your gas tank with about a half tank of gas. see what happens

 

ok will try.........and i drove it for 1/2 hour at night no glowing cat.........i think im running on less than 8 cyl

 

If the engine revs and sounds "ok" its not running on less than 8. Itll feel really out of balance (assumingy ou know what the car feels like when its running well).

Now assuming its not running "rough":
-If your high RPM (4500+) accelleration has gone to hell but he LOW rpm feels fine id put my money on the COIL, (possibly a clogged fuel filter or dying fuel pump, but my guess is coil).
-If your power is crappy above 2000 rpm and just feels like total crap from there up, (it can sometimes get progressivly worse over time as well...) its your CAT. On stock manifolds at night (has to be quite dark, not city lights dark) you may see the manifolds glow, you may see the cat glow. I do not recommend trying to do this though! Too much heat can warp your heads if your not careful....

Because you ran it without the maf and the problems persisted you can rule out most of the sensors.

Coles notes: I still think its your CAT.

 

I was reading this thread and I just have to add that the reason the car sounds like it had a CAI as you say is that the exhaust is muffled a lot more than it used to be because of a clogged cat or muffler (something in the exhaust is clogged for sure) and you can hear the air intake now, that's all.

 

Your cat does not have to glow to be partially clogged. My Sunfire daily beater had similar symptoms. It would idle just fine, but would be very choked under load. Full throttle went nowhere. New cat and all is well.

 

If it's laying down under power you need to check your fuel pressure. Check it at idle and if it's within spec for your year then check it under load. Just run the hose between the hood and windshield and tape it to the windshield where you can see it while you drive. As you get into the throttle the pressure should hold or possibly even climb a little from cruise. If the pressure drops 10 pounds or more under load you have a clogged fuel filter or dead pump. I'd bet if this is the problem it will drop more like 20+ psi under load.

This should be the first thing you check if it's laying down under full throttle and not missing like hell. When the fuel pressure is low you'll usually feel a surge like the power comes in and out a bit but not a bad miss.

Later, Michael