here is something about egr valves that i have found,, cleaning might not cure problem...!! i cleaned mine four or five times and i keep getting a egr code from ses light ... i installed a used one (instead of wasting $200) and it maid a WORLD of difference...... just a thought.

 

Sorry having a rough week. Sounds like a common ground issue. Check the wires on the frame above the gas tank (drivers side). A scan won't recognize a ground problem but multiple codes will tell you where to look or atleast a starting point. Dont start replacing stuff until you know the ground is good. I've done it twice and still have the same issues.

Mine started with the snow, road salting, and wetness. These coupled with electric components is almost a guarantee (atleast for me) that it is a ground issue.

I'm going to try to get to it in the AM tommorrow. I'll let you know how i make out.

 

I'm 95% sure your problem is the throttle positioning sensor. That will ALWAYS screw you over on hard accel and always screw with your tranny shift points. Get a new one and put it in, they aren't expensive.

Second guess for me is ignition coil. Mine was pretty gutless when the coil went bad.

 

Hmm...that sounds pretty quick and simple enough to replace. I'll have to look into that.

 

It might sound quick and simple, but it rarely ever is as simple as it sounds. I would think if the TPS went bad then it would stutter while accellerating, shake the entire vehicle. I had a bad TPS in a achieva once and thats what it did to it. It would drive fine until it hit round 35-55 and then it would shake and stutter like crazy and almost stall out unless i let off the gas then mashed it all the way down.

does it have any of these symptoms:

• Bucking and jerking of the vehicle
• Idle surging
• Sudden stalling of the car engine
• Hesitation while the driver of the car is trying to accelerate
• Sudden surge in car's speed while driving on the highway

If any of these or all of these symptoms happens then yeah your tps is shot.

Question though, have you changed the plugs, cap and rotor? I know it might not seem logical but sometimes the simplest things that you over look can be the answer.

Low Acceleration: Another symptom of a bad spark plug is low acceleration. If you find that pressing down on the gas pedal yields very little rise in speed, or if it feels like the engine isn't 'pulling', you may want to check for signs of a bad spark plug.

Mileage Drop: A common symptom of a bad spark plug is a drop in mileage. If you haven't changed the fuel you use, but are experiencing lower averages, take it as a warning sign. A noticeable drop in mileage can indicate a malfunctioning spark plug, or could be one of the signs of a clogged fuel filter. Use spark plugs recommended for your car for optimum mileage and performance.

Rough Idling: This is another of the signs of a bad spark plug. When your car is stationary, and the engine is idling, a sputtering noise, or a feeling of increased vibrations can signal a bad spark plug.

Sudden Surges: Sometimes, you might experience a sudden surge in power without a discernible cause. This could also happen when your car engine problems show up by not accelerating properly, or responding to continuous pressure on the gas pedal in fits and starts. This kind of inconsistent engine performance is an indication of bad spark plugs.

Engine Stalling: Bad spark plugs can cause the engine to sporadically stall. This may happen at frequent intervals, or just after the engine is idling.


If you haven't changed the plugs then do that. It might be the underlying cause of your problems and if you have, then id look more at the coil. But from what i've read thus far, you were more or less concerned with the muffler, cat, and fuel filter/pump. I was always told to change the plugs, wires, cap, rotor when you first get the vehicle (unles sit is brand new off the showroom floor) then change the plugs every 6 months to a year.

 

Well i went over most of my grounds, 5 of them, 1 on the rear crossmember 2 drivers side radiator support and 2 off the battery. I have also thought the TPS, MAF, MAP, IAT sensors could be at fault. But most of them have recently been replaced without success.

I will finish cleaning and replacing grounds, and then i will be bringing my 2000 to the tranny shop to have the torque convertor and tranny checked.

After I am done fixing it will be close to a brand new truck $$ wise.

 

It's gonna be a lot cheaper and easier to try the TPS.

Senshi, try reading the first post bud, its incredibly obvious the problem isn't anything to do with plugs.

 

i dont know if you fixed the problem yet and Im not sure what its called but try unplugging the sensor right off the air box hose I did this when I replaced my air filter and forgot to plug it back in and my 99 runs great until i plugged it back in

 

i had this same problem almost from new. i took it back and the said their was no problems. then it became hard to start for a long time. finally at about 70k miles i thought i might ruin the starter so i went to a shop and they replaced the fuel pump, i did the filter with no joy. well holy crap that fixed the starting and the power slump. this thing huals *** still 90k miles later. over 160k miles now on the clock.--dan