In 2006 the fuel system changed to a returnless

 

Thanks for the info my manual doesnt have. Ill buy the part this weekend. I dont get the gas smell any more but Im being safe.

 

Have you located the fuel pressure regulator on your truck? The fuel pressure is regulated by the fuel pump in the fuel tank.

 

No I havent looked for it yet. I figured it was up by the fuel rail like normal. When did it get moved that far back in the fuel system?

 

As GregDap said above. That is when they did away with the fuel line that returned fuel to the tank. The Engine Control Module (ECM) determines what the desired fuel pressure should be. It sends a signal to the Fuel Pump Flow Control Module (FPCM). The FPCM then controls the pressure by varying the speed of the fuel pump. The Fuel Pump Flow Control Module is mounted under the bed above the spare tire.

There is a fuel pressure regulator in the tank, but it is for overpressure conditions in case of failure of the FPCM.

 

in 2006

 

So my gas smell I had was nothing to do with the regulator. It cleared up a few days after my post about it but started when I cleaned the maf. Guess it was relearning.

 

Correct, it couldn't have been a regulator leak. There are, however, other fuel line connections that could develop leaks. There is also a test port with cap on it that could potentially leak. With a good part of the fuel lines made out of nylon, deterioration could be a problem too.

 

How bad of a problem is that. Mines an 08 with 110000 on the clock.

 

I believe he was giving you potential sources of fuel leaks. None of the listed are common problems from my experience. However they are possible.

If you continue to smell fuel, you need to give it a visual/smell inspection from tank to engine while running (while system is pressurized). A fuel leak is a fire hazard and a problem.

If you can pinpoint when and where you smell it, you should be able to visually see a leak or discoloration from where fuel has been leaking.

And of course if the smell disappears, you are probably fine. Monitor fuel mileage as always.

 

Thanks extremity. Your post is much clearer than mine. I was just pointing out that the absence of a regulator doesn't mean it is a leak proof system.

 

I smelled fuel on a cold start only. It started after I cleaned the maf and happened for a few days after the reflash now its gone

 

I'm new to the site but I'm going to jump in here. I have a 2008 colorado with about 90xxx miles on it. It started out like a miss or dirty fuel filter kinda stumbled or a little buck once in a while. So I spent about $300 and the better part of a day replacing the fuel pump assy. and it had no effect on the problem. So I replaced the spark plugs and tested all the coils all good still no effect. The truck will run fine then it will start stumbling, bucking and sometimes the reduced power light will come on. I shut the truck off and it starts back up and runs just fine. Oh it was suggested that I clean the throttle body which had some heavy deposits on it, so I cleaned it with the recommended cleaner shiny clean and I still have the intermittent problem. It gets worse when I put the A/c on really bogs down. The auto parts stores tell me they can't run a diagnostic without a check engine light which is not lit, only when it goes into reduced power but when it is restarted the light goes off. Sorry if I'm rambling but this is driving me crazy and not sure where to go or what to do next.
Anybody have this problem and know how to fix it?

 

If you go into reduced power mode, it should store a code in the module whether the light is on or not. They should hook the scan tool up anyways and check for stored or pending codes.

Most of the time it is throttle body related. As in I end up replacing the throttle body for this symptom a lot (after a proper diagnosis with a scan tool).