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I am getting a code 22 (low tps volts) & 33 (MAF gm/sec HI).
I have had this problem keep coming back for awhile. I have replaced the TPS & the ECM because a GM technician at the dealership said they were bad. Even though these parts were replaced the problem keeps coming back.
I just had a guy go through with a scan tool & set everything.
My questions are these,1. Could this be a wiring problem,2. The guy with the scan tool suggested if the codes come back it could be a faulty ignition control module,3. Could this be from the rumored K&N filter problem with MAF.
The code 33 went away for 6 months & I would get only a 22.
I notice before it throws the code my idle seems to fluctuate a little & after the code the car idles at 1000 rpm in neutral &
750 in drive as opposed to 750 in neutral & about 500 in drive before the codes. ( these are according to the tach).
I would deeply appreciate any help I could get, sorry for the length of the post but the length is in direct proportion to my frustration with this problem!!

 

The root of the problem is likely the '22'. A low TPS will cause the '33' very often. Checking the TPS supply voltage and TPS grounding/wiring to the ECM would be a good step.

 

How do I go about checking the ground/wiring for the TPS.
I tried the jumper on the TPS plug to see if you can get it to throw a code 23 & it threw the 23 for high volts. I thought this shows that the reference signal voltage is good. Maybe it is an intermittant problem with a ground or wire shorted.
Any info on what pins to check & any grounds besides the ground on the back of the cylinder head for the ECM it looks good, although I haven't taken it apart yet to check under the connector for corrosion. Any help would be deeply appreciated. This is the first real problem I have had with the car, I bought it new & it has only 31.000 miles on it.
It is always garaged so the engine bay is like new so corrosion shouldn't be a problem.

 

Meter the voltage across pins A and C of the TPS connector. There should be 5.0 VDC or something within 0.15 V of that.

Check voltage between the positive TPS connector (pin C) to a good chassis ground or the negative battery terminal. Also check the negative (pin A) to a chassis. There should be the same voltage from positive of the TPS to the chassis ground that you read across the connetor. There should be NO voltage from the negative TPS pin to chassis ground. Any voltage indicates a poor ground connection somewhere.

 

I have checked the voltage as you suggested. The volts across A&C are 5v. From C to battery ground are 5v.
Now the bad news the A to battery ground is .01 with the ignition off & 32.2 with the ignition on. I cleaned a chassis ground by the air cleaner that comes out of the wiring harness but that didn't do any good. Can you tell me any other liklely places I should check?

 

What The *BEEP*?!!

32.2V from A to ground? Dude (or dudette), that's not a good situation. There is a significant grounding problem or ECM problem.

Are you certain the voltmeter is locked on scale, or is it set to autoranging, and is scaling down to a mV setting to read the ground potential? Try locking the meter scale at some level/scale to be sure.

If you are definitely getting 32V at the A terminal, try grounding it with a jumper directly to a good engine ground and see if the symptoms change. If the ECM is regulating the reference voltage that much above actual ground, it's already FUBAR, so you can't harm it any more.

 

As you suspected I screwed up & forgot about the autorange. I deserve to be severely chastised. I rechecked & got .032 v with the range locked. I am terribily sorry to screw up so bad. I just got this meter & it's my first autorange, so it will take some getting used to!! I have noticed when I drove the car sunday that just before the code is thrown the engine stumbles just slightly. Could the 22 be a result of this? Maybe a bad ignition module? I have been told these have been a problem with tpi cars. Again I am sorry for the bad info!!! By the way it's DUDE. The tabboo is a nickname hung on me at work. I hope this correction helps find the problem. I seriously appreciate all your help. I will always pay special attention to the range on my voltmeter from now on!!! ( lessons learned the hard way are always remembered)