I've read posts on here for a while but have never posted. I've searched the posts multiple times to try to find an answer to my problem but have not been able to find it. If I missed it and it's already been answered, I'm sorry.

I have a 2005 5.7 Hemi w/ 75,000 miles. My truck died a couple of times over the last month when I was going up a hill and took my foot out of the gas. So based on recommendations on here, I cleaned my TB and thought it would fix the problem (or at least not make it worse). I put everything back together and now it does not idle right. The first couple times I drove it around it would die at stop signs, red lights, etc. After a few trips it would get better but it would still rev up a few times at a red light and wasn't right. I reset my PCM hoping to fix it. Each time it's a little better but it's still not right. Does it just take a while for the computer to relearn or is there something else wrong? Should I just keep driving it since it seems to be getting better each time out?

Thanks for your help, and again if I missed something obvious or this has been answered I'm sorry.

 

Welcome to the site.

You can try resetting the PCM to see if that helps. Obviously you cleaned the TB correctly because it does work and obviously you do have it installed correctly and the harness connected to it. Other than that, thats it. Do you have any CELs? It could be the front O2s making it run rough or a bad EGR valve. I think we need some more info from you.

 

Thanks for the reply Weed. I don't have any CELs. I did reset the PCM and didn't notice much of a difference. When I'm driving on the interstate or accelerating in general it seems to run great. It's more of when I'm slowing down at a red light or letting out of the gas the engine will some times rev and lurch forward and acts like it may die. It doens't do it every time. It seems like it's doing it less frequently the more I drive so I thought maybe the computer was just relearning.

Would I get a CEL if the EGR is bad or if the O2 sensor is bad?

 

More than likely you would get a CEL if one of those were bad but it takes 3 consecutive trips of a sensor to make the CEL/MIL come on. So it IS possible for it to be bad and not come on. Likewise it could come on and go off if it doesnt get 3 consecutive trips and that tricks a lot of guys thinking their problem went away.

 

After driving for 2 days I thought my problems had gone away. After a few trips the truck seemed be driving better than ever. However, on the way home tonight the ETC light started flashing at me when I came to a stop sign. And then it went into limp mode. I turned the engine off and restarted it and the ETC light went away and it ran fine the rest of the way home. Could a bad EGR cause the ETC light to come on? Thanks for the help.

 

did you reset the butterfly in the tb to the same position as when you took it out, sounds like the truck is getting more air and it wants and its not matching the calculations and it stalls

or could be a bad/lose connection

 

I thought that I had put it back exactly the same. It has generally run great the last 2 days, including this morning. If the butterfly was in the wrong position or there was a leak wouldn't it still run rough after I restarted it?

 

The butterfly cannot be in the wrong position. It is mechanically installed on the shaft and the shaft is is mechanically in place by a coiled spring inside the TB housing. When you first flip the key on without starting the engine the TB is auto-calibrated.

The ETC light should trigger a CEL/MIL though. Do you have a tuner or ODB scanner?

 

I don't have a tuner or a scanner. I tried the key trick but it just said done. I'm gonna take it to autozone this afternoon to see if they can pull any codes. Can codes still be pulled if the check engine light/ETC isn't currently on?

 

The ETC light started flashing at me again last night so I took it in to the mechanic this morning. They said a code for high air flow or vacuum leak was the only code that was coming up. They went over the engine multiple times and could not find a problem. Any other ideas on how to fix this problem? It runs great when it's running and there is no warning that it is about to fail.

Thanks