Gents,

I have had an issue that comes up about three times a year, since I bought the truck. I start my truck and always let it idle for a couple of minutes. Today I did just that and when I put it into gear everything seems fine. When I back out of the driveway, everything seems fine. Put it into drive, and no power. The truck will move, but very slowly and the engine stays at a low rpm. The throttle doesn't help this. Part throttle, wide open, and still no difference. I usuall stop, give it about 1/3 to 1/2 throttle fast, usually she hesitates and suddenly takes off and runs fine for the rest of the day adn usually months after this.

I have no codes. I never see any boost in this situation, but there is little rpm for boost either. I have cleaned the MAP. I have checked my harness for rubbing many times. I have a hose under it to protect it. I don't think its an Ice pick fix, but I have done this before. It has done this before and after I added a lift pump. The fuel filter has never been the issue. The time before this, I ran the fuel filter another 5K+ with no issues. I change all fule filters every 8K.

The truck has been warm and it has still happened. I think it happens more when it is warmer out than cold but it does it at any temperature. It is really hard to troubleshoot becuase it is running fine now and I have no codes etc.

I am thinking either the FPR valve or the Turbo vanes are sticking and or its Turbo related. My exhuast noise has changed a litte over the years. Sometimes it sounds like the turbo stops at an idle, then starts. It used to slow way down, but not actually stop, but it comes to a complete stop now.

Any Ideas. The truck is fine now, but I would like to figure out what is causing this. Any help is appreciated.

turbo bushings going bad?

I've never had the trubo apart. I would have thought it had bearings not bushings?? It does seem like the trubo is stuck or the vanes are sticking.

Any ideas???

It did it again last saturday. I started the truck, backed up, no gas needed. Put it into drive, went to take off and nothing. The truck went up to about 1600 rpm. I had it floored. It made about 4 pounds of boost. It did this for about 10 seconds, then took off like I stole it. It has ran fine since the incedent. No codes. I didn't look for smoke, so I don't know if it is fuel or boost.

If it is fuel, I need to hook up my predator and leave it so I can see if the rail pressure is really low.

If it is the vanes, it should be puffing smoke.

As it is getting more frequent, I should get more information.

Does anyone have any ideas??
I have searched and searched to no end. Any suggestions would be appreciated.

was going to say injectors but you say it does fine in reverse just when you put it in drive after your out of your driveway....so yea maybe not enough air, id check the turbo and possible if your curious do something to clean your injectors....i know you dont have a lb7 tho :)

Just a thought but have you check the wiring to the throttle position sensor or the sensor itself?

Just a thought but have you check the wiring to the throttle position sensor or the sensor itself?

I was thinking that the throttle wasn't working or sticking.....If I remember these are drive by wire and don't have a cable that goes between the pedal to the throttle body

I was thinking that the throttle wasn't working or sticking.....If I remember these are drive by wire and don't have a cable that goes between the pedal to the throttle body

What about a gas pedal that's failing? Maybe you could try one from a Toyota, they seem to go to WFO pretty easily. :p:

What about a gas pedal that's failing? Maybe you could try one from a Toyota, they seem to go to WFO pretty easily. :p:

LMAO

It did it again today, but this time I did get a soft code. P0101 Mass Airflow sensor.

I've cleaned it several times, but I will clean it again. It does seem air related. I'll check the trottle sensor as well. The Mass Airflow seems a little expesnive when I just briefly looked for one... pushing $300.00 I have looked at GM Parts direct, Rock Auto and OEHQ. All pretty close in price. Is there a better source for a MAFF??

Don't do like I did with the Maf sansor and replace it without checking it. I think I paid $365 for the stupid thing only to not fix my problem with that code. In my case the finger stick had failed sending a constant voltage reading to the ecm. Once I got that thing out of the way all my probs were solved minus the $365 sensor of course (they wouldn't take it back).