TXPalerider

I have a 2003 Chevy 1500HD w/ a little over 100K miles.

Recently, my Check Engine light comes on (steady) and the truck will go into "reduced engine power." However, there is no consistency to when it happens.

Sometimes it might happen 3 times in 20 miles and then not happen for the rest of the day. Other times, I may drive 100+ miles in a single trip without any problem at all. Just Sunday, I drove 145 miles from out of town with no problems, then it did it less than 1 mile from home.

Any suggestions? Without any consistency to the occurrence, I don't know where to start.

Thank you in advance for your help/input.

adam86107

Sounds like it could be a number of things, best thing to do would be to take it and have a diagnostic ran on it next time the light comes on. Doing so will give you somewhere to start troubleshooting.

TXPalerider

As a moderator on another forum, I know exactly where you are coming from. That exact thought crossed my mind before I posted last night. I truly appreciate this forum and the knowledge it provides. I have found other useful information on here, even when I haven't posted a question. Unfortunately, I don't feel I really have enough knowledge about Chevy repair to be able to make any real meaningful contribution. I will be more than happy to go back later today and see if I can't provide any useful follow up to my previous questions.

In the meantime, hopefully that won't preclude any of the more knowledgeable members from replying to my question.

PS....if anybody has any questions about hunting, fishing, or outdoor equipment, please feel free to PM me.

TXPalerider

Thanks Gary.

A little update on my problem........

It did it to me again this morning, so, I turned right around and headed to Auto Zone to have them check the code. Here is what it showed:

Code: P1516

Definition
TAC module throttle actuator position performance

Explanation
ECM has detected an out of range condition between the predicted and actual throttle position

Problem Cause
1 - Poor connection at the TAC module
2 - Failed TAC module
3 - Check TPP or TPS sensors
4 - Binding or bent throttle plate-failed throttle body

However, the guy at AutoZone said this was a "manufacturer's" code, so, he wasn't real sure what the problem is.

Based on my description of the problem and the information I received from AutoZone regarding the code, can some of you more knowledgeable guys give your educated opinion on what you believe is the problem. Where would you start?

Keep in mind, I have know real clue about any of this.

Thanks

adam86107

I found another forum that talks about this problem and it seems a pretty common fix is to change the TAC. Before doing that though you might wanna check the wiring going to the TAC and make sure it isn't broken or grounding somewhere.

TXPalerider

Thanks for the reply.

I've been planning on checking the connections, but, it has been cold an raining the last couple of days. Hopefully, it will be something as simple as that.

tat2dup81

best thing is take it in. i just did today and my prob was a faulty plug that made wire go bad. so that threw off everything in my system. $100 shop bill better than $1000 in parts replacing. sometimes you gotta spend a lil to save alot.

Dmontray Brown

So I did my own tune up on my 2003 Chevrolet Tahoe and I changed 7 spark plugs instead of the whole eight and now a month after I did the tune-up is telling me that I reduce the power so I read the comment in a dude said something about a spark plug can make it reduce power because it's messing it up yeah let it get that is the problem I feel like that is the problem because I changed all 7 spark plugs without changing one and now all of a sudden is telling me that I have reduced power so when I do go to the mechanic shop and properly get the spark plug change I will update you and let you know if you know things change but right now I am not able to drive over 20 miles an hour and it sucks

jake sorensen

I would test the throttle position sensor iv had many go bad if u dont want to pay a fortune for a new one try a local pick and pull