I assume with all the leak stuff you had and maybe still have a clear line on the return off the injection pump to look for bubbles? It just seems odd that the issue is in those mid RPM's, its not like the injection pressure is changing depending on rpm so faster or slower should not really be working around an inector issue. Have you had a pressure gauge on it to make sure its keeping a positive fuel pressure? I have done it just taped to the hood or mirror to verify whats going on.

 

Is your stepper motor working on the IP? What is your timing at w/ scan tool?

 

I assume with all the leak stuff you had and maybe still have a clear line on the return off the injection pump to look for bubbles? It just seems odd that the issue is in those mid RPM's, its not like the injection pressure is changing depending on rpm so faster or slower should not really be working around an inector issue. Have you had a pressure gauge on it to make sure its keeping a positive fuel pressure? I have done it just taped to the hood or mirror to verify whats going on.

I do

I assume with all the leak stuff you had and maybe still have a clear line on the return off the injection pump to look for bubbles? It just seems odd that the issue is in those mid RPM's, its not like the injection pressure is changing depending on rpm so faster or slower should not really be working around an inector issue. Have you had a pressure gauge on it to make sure its keeping a positive fuel pressure? I have done it just taped to the hood or mirror to verify whats going on.

i do have a clear hose on the return line but honestly haven’t thought to check it for air bubbles as the truck had run fine at idle and low rpm’s after changing lines from filter housing back and the tank and pickup. I will look for that tomorrow for sure. I am a little baffled as the truck will sit and idle and runs very smooth at lower rpm’s. The missing starts about 1500 very slightly, but by 1700 I’m getting white smoke and a pretty heavy miss.

 

I do

i do have a clear hose on the return line but honestly haven’t thought to check it for air bubbles as the truck had run fine at idle and low rpm’s after changing lines from filter housing back and the tank and pickup. I will look for that tomorrow for sure. I am a little baffled as the truck will sit and idle and runs very smooth at lower rpm’s. The missing starts about 1500 very slightly, but by 1700 I’m getting white smoke and a pretty heavy miss.

So it starts around 1500 rpm and continues the same as rpm's increase from there?

I would tend to side with those who think there might be some air infiltration somewhere.

Steve

 

I guess we should be asking not just assuming that it does smooth out again at high R's?

 

X2 on post # 3 Re: Stepper Motor. P0216 when cold means the PCM is not seeing the timing it expects. Possible that the Stepper motor may not be advancing timing for cold starts and setting the code. Check connections and for proper operation of the Stepper Motor.

 

It's pretty easy to tell when the stepper isn't working, the 'out of time' clattering is really apparent.

Steve