I've been searching this site (and the whole damned net) for three hours now, and found hundreds of code 22 threads for TPS low voltage. However since none are duplicates of my problem, and some don' even have resolutions, I thought I'd throw this out there.

My problem is a code 22 tps low voltage. When I check voltage, I get the 5 volt from the ECM like I should, and it is adjusted to .55. Then, when I start the car all the voltage drops, and then the ECM throws the code 22.

I'm not sure what's going on with the voltage drop, but I have no idle, the motor sputters, runs rich, and dies. Takes about 3 seconds for code 22 to set.

I've already followed the code 22 diagnostic tree to the end.(jumper, code 21 yadda yadda) Then reset the ECM, readjust the TPS, get it perfect! Start it and poof! Problem reappears, car dies.

It's a new painless wiring harness, and new TPS. Like I said, adjusted to a tee, ECM is giving me 5 volts, and it's adjusted to .55 at idle, 4.2-4.5 at WOT.

I guess I just don't understand why when the ECM is reset and I have the TPS adjusted perfectly, the voltage drops when I start and run the car.

Any thoughts?

 

Ok so you could have one of many problems but first thing first.

1) check circuit 416, it sounds like to me its an open circuit or it is shorted to your ground. if this checks out check 417

2) 417 could be open, shorted to ground, or shorted to sensor ground circuit if circuits are fine...

3) check ecm connection, loose wires or bad connections will result in low voltage.

4) disconnect your TPS and with a meter, connect circuit 416 and 417, voltage should read 4V

If all checks out it could just be a faulty ECM in that case... well you know what that means... email me at kcooks12@yahoo.com if you have any questions. Hope this helps =)

 

Ok! So, I checked all my wires again, as as I would have expected from a new harness, no problems. Checked all ecm connections, cleaned the connections.

I got 4.6 volts when testing 416 and 417. Still getting a 5 volt reference at the tps, but now I can't even get .100 volts at ckt 416. Can't adjust it any higher. Even WOT barely changes the voltage reading, and I'm getting good contacts with my meter, so I am at wits end.

I just wanna replace both ECM and TPS, but that's just frustration.

 

Ever have one of those questions you feel dumb for asking? Here's mine...

Does the case of the ECM need to be grounded? I have the ecm ground wires grounded to the block, but not the ecm case, it's just laying on my floorboard.

 

I found that when my idle went hay wire that my tps bolt had stripped and was broken that I had to adjust it like you did but that it wasn't tightening as well as it should have been since the threads in the hole were stripped so it would 'self loosen'. I had to drill and tap the hole and I went with some hex bolt screws to sort of keep the same idea.

Tightened it to .54 and now my idle is good.

 

no the case of the ecm does not have to be grounded. Is there a chance that the cars over all voltage drops? The ecm will have probs if it drops below 10 volts and thats stretching it. 12-11 is the min. Other than that i would agree with the above post sounds like there is a open or shorted circuit. I have never had good luck with painless harnesess, use a volt meter and read out the wires from one end to the other.

 

I did figure this much out.

I checked the pinouts at the ECM...all are receiving the right voltage at the ECM. So, the ecm is getting the proper information. I guessa new ECM is on order?

 

I'm not sure if you've resolved this yet, but I had a similar problem when I put a painless harness and 350 in my Jeep. The jeep would start and then quickly die. I did not check the codes, but I ended up finding out that the 12v power wire I had feeding the ECM was not big enough. Seemed ok but when I started it up, the extra draw from the computer seemed to reduce all of my voltage output. I installed a larger gauge wire for the feed and I haven't had a problem since.