Yes injector clean is safe, But is PM and is not a fix! You have spent enough im sure, So save your money as far is this goes! Im not saying im right or trying to be a hero, But I have been working on these engine for many years. From reading your posts you have covered most of the system witch is pretty simplex. But Diag can be very complicated as you see. I dont have alot of time to login to this site latley.. (Its motorcycle seasion) But from reading your post 3 things come to mind... EGR, IAC and Base gasket.. Are these items new, Have they been dissasembled inspected/tested? might be some what trival but didnt see it covered in your post nor did I see mention any other testing leakdown/comp..etc

Again,
Best Wishes

 

Have you replaced the pcm? something seems off with not using the same year TBI then keeping the older pcm setup I tend to think the problem lies there.

 

He just tried the throttle body off a newer truck and then he put mine back on. It was just a trial thing. He swapped alot of parts with no luck. The egr has been replaced twice, the IAC actually has been replaced 3 times, and the tbi gasket has been changed 2-3 times with no change. My truck has a ecm with the calibration chip. The computer from the newer truck would not work in my truck so he put it back. So I got a new one from gm and we tried that and it didn't work. I am thinking about trying to find someone who has a throttle body that is not using it to let me take it off and try it but I guess it needs to be from the same year. That might be hard to find. I have a friend that gets me parts from gm at cost which helps but the whole assembly is like 800.00. This is the 2nd new engine with the same idle problems exactly so the engine is ruled out. Even my old engine did the same thing that came in the truck. That is what I have been trying to fix for 21 months. We thought because the compression was low on some cylinders that it was the engines fault but it didn't turn out to be fixed and the guy that put the engine in wanted to blame the new engine so I had to leave him. He wouldn't give me any of my money back and he is the one that messed up my old tbi housing.

 

If I were in your shoes I would have driven the ****** off a cliff then blown it up a long time ago.
Sounds like something is wrong with the engine managment I wouldnt sink any more money into count your losses and trade it in.

 

21 months of time in this thing and you havent gotten that ONE problem fixed.....blow it up

 

I have had this truck for 14 years with no trouble and then this idle thing came along. I have wanted to show this truck for along time and finally I am able to do so. I am attached to the truck and it is a nice one besides this problem. I know someone can figure it out.

If it is something with engine management then it should be able to be fixed. People take cars completely apart and put them back together and they work after that.

 

have you had the pcm reflashed, make sure they throw in all the updates.

 

dang... this is weird than, at this point you can only hope its something simple, lol but it doesnt sound like it.

what about those cats/o2's? still didnt solve anything... bc you say this exhaust odor is going hand and hand with the idle and drivability issues right? i guess what im trying to ask is if you noticed the exhaust being pungent like it is when you noticed the idle issue, like did they occur at the same time?

 

Make sure you have the right injectors ! I did that , and it will run like crap. They are color coded and have a # on them. Also try another dealership . They might not be as good as thay think thay are.

 

The injectors are the original ones.

The ecm showed to not have any updates for that year.

The smell did seem to happen at the same time as the idle problems. I have been saying that to all these mechanics I went to but nothing rings a bell. I don't know if the dealer has the diagnostic tool to read exhaust backpressure or not. They told me they had to take the cat off to see if something was wrong with it. So I don't know.

When you barely give it throttle either sitting at idle or going down the road you can feel it missing or something. It is not smooth whatever it is.

I am suppose to take it back to the dealer in a few weeks. He is suppose to get a friend that is a driveability expert to help him. I wonder if I had a tech 1 tool if I could figure out what is going on. I just don't have the diagnostic tools they should have at the dealer. I hope they are using at the dealer and not just standing back and guessing.