When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Hey guys, I recently purchased a truck that has a L98 from a 86 C4 swapped in it. The engine turns over and idles fine, but when you give it gas it sputters bad and had a strong smell of fuel in exhaust. After hours of researching I narrowed it down to a possible faulty fuel pressure regulator. Pressure gauge helps confirm that it's bad (getting 58 psi instead of the 43 psi with no change when pulling vacuum hose from FPR).
Any way I have purchased a new FPR and when I began to take apart the intake and throttle body, I seen a vacuum line staring me in the face and I don't see where it would connect. It's on a bracket that has another line going to EGR valve. Should this be connected to anything or did it go to something that's no longer needed since it's been swapped? It looks like it has not been connected in a long time. Thanks for your help.
That vacuum line connects to a port on the bottom of the throttle body. It supplies vacuum for the EGR valve, which is controlled by the EGR solenoid, which is where the other end connects. This is what mine looks like:
Thanks. On the bottom of my throttle body, that fitting is capped off with a rubber plug. Should this have not ben capped off?
it should be connected, GM would not gone to the trouble to design not to use. also some of what you have discribed could be EGR related. so do your Fuel system repair with the plenum out of the way take a good look for monkey bussines. as you said its a upgraded pick up. So some of what should be and what is out the window.
Need help identifying vacuum line.
