1994 Sierra Fuel Filter
 

I have a 1994 GMC 1500 4.3L and I'm loosing power when I get up around 65-70 mph on the highway. I think it might be my fuel filter or fuel pump since I had a new engine put in it last summer. I was just wondering if anyone knows where the fuel filter is located on this model of truck. Thanks.

RE: 1994 Sierra Fuel Filter
 

its under the truck,on the left framerail..pretty much under the driver

RE: 1994 Sierra Fuel Filter
 

Ok, thanks. I figured that I would see if that needed replaced before I messed around with the fuel pump.

RE: 1994 Sierra Fuel Filter
 

more then likely its either your 4.3 itself or your rear end gearing.

RE: 1994 Sierra Fuel Filter
 

I thought it might be the engine but I bought a completely new one by Jasper Engines and they supposedly fixed the problems that the 4.3 had. The engine idles good at rest and accelerates good from a stop so I kinda thought at higher speeds it might be a fuel delivery problem. but im no expert just a college student trying to fix things on my own to save money. Thanks for your help.

RE: 1994 Sierra Fuel Filter
 

did the truck originally have a 4.3 in it?

RE: 1994 Sierra Fuel Filter
 

Yeah it had a 4.3 in it. It idles and perfoms ok at low speeds it just has trouble when I get up at higher speeds over 60. My mpg has dropped a lot over the last week or so also. I was driving around town today and I used a 1/4 take of gas, but i only drove 30 miles. I figure its either getting too much fuel or not enough. Im not sure though.