V6 Silverado 1500 Very Rough Idle & Oil Pressure Varying
 

Hello Everyone,

I've looked all over the web trying to figure out what my problem could be, and now I ask you.

I have a V6, 2001 Silverado 1500 LS, 136k miles, new spark plugs and fuel pump.

About a week after my change oil light came on (just short of 3k miles actually), it started idling very rough. Just recently, I changed the oil (Pennzoil synthetic) hoping that would fix it, but it's only gotten worse. Every few seconds while idling it shakes, and it sure feels like it's coming from the left (driver) side of the truck. When the shake occurs, the oil pressure dips about an 8th of the way. Once the shake stops (it last about a second) it goes back up to halfway on the dial.

From what I've read, it could be either a clogged fuel filter (I honestly don't remember the last time it was changed), problems with the fuel pump relay, or maybe a bad oil pump. I don't quite think the oil pump is bad, because except when that shaking occurs, the pressure is fine. The truck isn't running hot either, but maybe that screen that filters the oil has gotten clogged.

I don't see the pressure move too much while driving, and although the truck isn't shaking like crazy, I think it's still kinda rough. May be the rough though, not sure. The problem lessens a bit when I put the truck in park instead of just holding onto the break, but it's still shaking roughly every few seconds. If I accelerate during a rough spell, it takes a second to get going, but otherwise accelerates fine.

Any ideas? And thank you very much. If you think it is the fuel filter, can someone help with ideas on how to replace it myself?

look under drivers side of frame, tucked inside of channel of frame, you should see the fuel filter. round canister, bout 3" or so long, fuel lines on each side (in and out). pair of wrenches (i believe a 3/4" and a 5/8", but i could be wrong) also may have to loosen or remove the retainer bracket. just loosen the two lines, replace filter. be ready tho, you will more than likely get fuel spill from filter. have new filter ready. pull old one and immediately get new one in place. or to make things a bit easier, get front of truck in air, putting filter above gas tank. should eliminate the fuel pouring out of lines too much. good luck.