TABBOO

I keep getting a code 22 (low tps volts) & 33 (MAF).
I have replaced the ECM (chevy garage said it was bad) & tps
same deal. The garage was wrong. I keep having this problem. Could the MAF be bad? Could I just need to reset the minimum idle? anybody got any ideas? Help!!!!

GMTech

Make sure minimum idle is correct, then double check the adjustment of the TPS. Do you still set TPS codes with the new one installed?

doc

If you paid the Chevy dealership for a new computer, and you still have the same problem, I would take the car right back to them.
Where did you go, to Ewing (sp).

TABBOO

I paid Progressive Chevrolet, last fall. They wanted $400.00 for an ECM, $75.00 for a tps & $200.00 to install & set them.
I told them to forget it & bought the same ECM for $150.00 from an AC Delco parts dealer & the new TPS for $40.00.
I installed them myself & the codes went away for awhile.
I did this last September & drove through October & put the car in storage. I didn't get the codes again until I brought the car out this spring. I don't drive daily, the car only has 31,000 miles since new. It was a little late to go back on the chevy garage about a bad diagnosis. After taking the car out this spring I started getting code 22. Now the last few times I am getting 33 also. I had a guy with a scan tool set the TPS & check out the operation of the ECM. He said everything was OK when he had the scan tool on & he didn't get any codes.
The second time after I drove it the codes came back. (no going back on him, he did it for free). I will try to set minimum idle & check timing & recheck TPS to see if it goes away.

doc

I use to get the 33 error code, also. I reset the TPS several times, but the code kept coming back. I had to program my own Eprom chip to get rid of the 33 error code.

The 33 error code is set when these three conditions are met simutaneously:
1) under 2000 RPM,
2) over 45 gms/sec reading from the MAF, and
3) less than 25% throttle (this value is gotten from the TPS).

After porting the plenum and installing large tube runners & a ported intake manifold, I would meet the above conditions when in overdrive at about 60 mph.

So, where are the cruise-in places in Canton these days?

TABBOO

Did you also get the 22 in conjunction with with the 33?
My car is completely stock. I do have a K&N and I did remove the screens from the MAF.
By the way the big cruise in in Canton is at Arby's in North Canton on the north side of town, every Sunday. It is a real informal cruise in just show up & show what you got.
Do you know anywhere to get a chip to stop the code?
My car runs perfect right up until the code shows up.

TABBOO

Thanks for the help. The problem turned out to be a couple bad pins in the ECM connector & a frayed TPS wire. I had to take it to a wiring specialist but it is fixed now. Thanks again!!!

Jackman5003

well lets get this post going again. i have the same problem. i have replaced the MAF, TPS, and the two MAF related releys. it only throws these 2 codes when idleing for, say, 5 minis. and then again when i'm crusing along on the highway. i'm clueless now. i KNOW my tps is set right, timeing does seem to make it a bit better but its set at about 10 advanced now because it throws the code less then at 6-8 degrees???

i do have a significant exhaust leak. but its been doing this since the leak was pretty small like. but maybe thats throwing everything off? it does idle kind of rough with the codes showing or not.

what else is on the MAF and TPS circut?

TABBOO

Check your ground on the passenger side behind the cyl. head. This is the ground for the ecm. I found that I had a TPS that was shorting internally. This really sucked cause it was a new TPS from AC Delco, not some cheap piece I thought ( still made in china!!). I hope this will help you.
Also check the throttle plates on your throttle body to make sure they are moving OK & not gunked up or bent.
GOOD LUCK IT COST ME $500.00 TO FIX THIS PROBLEM!!

Jackman5003

that ground is fine. i cheaked it and i know its fine because its also grounding other various things from the wireing harness out.

i JUST put on a rebuilt throttle body that was sandblasted and had new blades put in. so i know thats good...


and ok, i went outside and went STEP BY FREAKING STEP from the manuel i have to set the minumem air, then the TPS voltage. now, i went to start the engine, first time it didn't want to but i gave it a bit of gas and she started right up. then i shut it down to try and start it again to make sure everything fine. she started right up. but the idle, OMG, it was at about 1600. so i said screw the book and just brought in the minemem idle screw till the idle went down to around a grand. then reset the TPS voltage. well ok, its fine now, i even disconnected the battery for 5 minis to clear everything and start from scratch. well guys, now its got code 21. the connecters reconnected and all(manuel told me to dis-connect it). i also didn't really take the car for a spin, just around the block a bit. think that would be enough to set the codes 22 and 33 again? hopefully so eh?

so why would i have code 21 now? i didn't fry anything you think did i?! could it jsut be that the timeings off. i did set it a couple weeks ago but that distributers SORTA lose in there. i did fiddle with iot a bit trying to shut the code up but didn't do anything...


sorry for the long post...