Hi everyone. I'm new to the forum. I just bought an 01 GMC with 212,000 miles and I am having some issues. This is not my first Duramax. I had an 04 Chevy. I also had two VW diesels. Anyway, this truck is new to me. I've been searching for info about some problems I've been having and stumbled on this site. I've liked what I've read. The site seems more friendly than a lot of the others I've belonged to.

Okay, so the problems...A couple days ago the Service Engine light came on. The truck has been running rough at idle. Sort of a surging. It also has a strong smell of diesel when I park it in the garage. I know diesels smell, but this is unusually strong. It has had plenty of power when I ask for it. It just runs rough at idle. I took it to have the code read yesterday and it came up p0089. I read on here that my symptoms as well as the SEL indicate a bad FRP. It looks like this is something I could do myself even though it will take all day. The weird thing is I went to drive it this morning and the SEL was off and it was idling perfect.

Is the FRP something that can be intermittent like that? I'm deathly afraid of my injectors going bad. I bought this truck to get rid of a lot of debt. I know it is pretty high miles, but for a diesel it is not that bad and I now have a short commute and will only be putting about 7000 miles a year on it. I figured I could get at least 5 more years out of it at that rate. Based on what I've read it seems like I would have some performance issues if it was the injectors. There is no excess smoke. In fact I've tried to get it to smoke and can't. The oil doesn't seem to be overfilling...Sorry for all the rambling. Any advice would be appreciated.

Oh, there are a couple of mods that I bought it with. It has a K&N intake. I know these suck, but I haven't had a chance to change it yet. It also has the muffler removed. That is all that I know about.

Thanks!

 

Update: The light came back on. It started idling rough again. Based on threads I read on here and elsewhere I thought it may have something to do with the FRP Valve. I read that lack of lubricity can cause it to stick. So I went out yesterday and bought some Power Service and some Two Stroke Oil. I put 16 ounces of PS and 8 oz of two stroke in a full tank and drove around for a while. The light went out and it is running like brand new. I guess it could be coincidence, but I hope it fixed the problem. I definitely will be putting in the Power Service and Two Cycle in my tank from now on.

 

check your oil for fuel in the oil....for sure sign of bad injectors. How does it do when you tow? There is an easy mod to increase your fuel psi with some washers here on the boards. I did it a few years ago and it was easy, but did not fix my problem. I had a bad fuel pump

 

You need to check bal. rates on injectors, frps can be intermittant and stick ocassionally usually you can check by unplugging the fpr while its acting up and see if the idle smooths out.