Hello all, I have an H2 with a problem and hopefully you all can help me. I've read some of the posts and this has been asked before but not with my specific problem. So, a couple of weeks ago I was driving along, been driving fine all morning, when the engine bogged down and I got the reduced engine power message. I pulled over, turned it off and started it back up with no problems. I checked everything and I did notice the coolant was a bit low so I topped it off and drove it daily until yesterday. It did the same thing only this time I can't get it to run or get the check engine light off or the reduced engine power message to go away. The fluids are all good and I haven't done any work on it. Any ideas on what I should do next? Thanks.

 

Need to get the codes read, wouldn't be surprised to see a knock sensor code. Also what year, mileage, length of ownership, where and how you drive would help. You may get evrything to reset by removing the negative battery terminal for about 10 minutes. Check your coolant again, too.

 

It will go into reduced engine power when accelerator position sensors don't match or throttle position sensors don't match. Does that due to not knowing which of the sensors is correct. Need to read codes. If you have a p2135 you need a throttle body. Could simply need a throttle body cleaning and idle reset for some other codes. May need throttle pedal if p2138 is set. too many variables without knowing which dtc is set.

 

ive had a lot of experience with this on my old silverado ss. it was 90% of the time throttle body related. could also be a loose connection from any major wiring harness under your hood.

if you do not have any engine codes just double check and make sure you dont have a harness that is coming loose or making poor connection. if all is good just drive it

 

Thanks everyone, I went down to Auto Zone and had the codes read. I got two readings, throttle body sensor and throttle circuit B. I guess i'll take it to the shop and have it repaired. It's going in for a coil spring conversion anyway.

 

BTW, the codes are: P0220 Throttle/Pedal position Switch B circuit, and P2135 Throttle Position Sensor 1-21 Correlation Error.

 

I would suspect a broken or partial broken wire at the throttle body connector. One way to tell is to grab each wire about 1 inch or so away from connector and pull on them, if insulation starts to stretch and change to a white color that means wire is broken inside the insulation. Keep in mind if you break it it will need to be repaired or towed to someone who can repair it. Once its broken it will be in reduced power mode till its fixed. Ive seen many shops replace throttle body as soon as p2135 is set, most cases that's what it is. Would suck to replace perfectly good part for a wiring problem though. Just a heads up

 

BTW its the p0220 that makes me lean towards wiring issue