Yet Another No Start Issue
Thread Starter
Intermediate
Joined: Nov 2022
Posts: 34
Likes: 7
From: Buffalo, NY
Yet Another No Start Issue
Sorry, It's a bit long, but I want to give all the info. I'm getting desperate over here and about to just start replacing all the fuel components and call it a day.
I recently replaced the intake manifold on my '89 (TPiS base, AS&M runners, port match plenum). While I was in there, I replaced water pump, gutted air pump (and removed all other parts/plumbing), added an adjustable FPR (with new diaphragm), and replaced original rockers with Comp 1.6 Magnum rollers.
I got it all back together, haven't adjusted the timing yet, but set it to TDC and pointed rotor to cyl #1. Put a gauge on the fuel rail and gave her a couple key turns.
Here's where I think I may have F'd something up - I forgot to prime the fuel system. I wasn't getting pressure (forgetting there's still air in the system), and cranked it a few times until I remembered, and hit the pressure relief on the gauge. Now I was getting pressure, but like 60+ PSI because I didn't know where my new FPR was set. I adjusted it down to 47/48 PSI, still getting pressures inbetween as I slowing adjusted it down.
It WAS holding pressure. Now it will not hold pressure at all. KOEO, it shoots right up to 48-ish, then I hear a click (fuel pump relay?) and it immediately drops to zero. If I KOEO immediately following this, it does nothing. But will do it again if I give it a minute or two.
I've pinched off the return line the best I could (they really dont leave much room where the rubber parts of the lines are) and it still does it. I also pinched off the sending line (also the best I could), and it still does it. Which makes me scratch my head even more, because if I had the send line pinched, it shouldn't have even got initial pressure, right?
Injectors are stock, and fuel pump is stock as far as I'm aware. Both were working great before I did this so I didn't replace either. But now, I'm thinking I "killed" something with that initial spike of 60+ PSI.
I recently replaced the intake manifold on my '89 (TPiS base, AS&M runners, port match plenum). While I was in there, I replaced water pump, gutted air pump (and removed all other parts/plumbing), added an adjustable FPR (with new diaphragm), and replaced original rockers with Comp 1.6 Magnum rollers.
I got it all back together, haven't adjusted the timing yet, but set it to TDC and pointed rotor to cyl #1. Put a gauge on the fuel rail and gave her a couple key turns.
Here's where I think I may have F'd something up - I forgot to prime the fuel system. I wasn't getting pressure (forgetting there's still air in the system), and cranked it a few times until I remembered, and hit the pressure relief on the gauge. Now I was getting pressure, but like 60+ PSI because I didn't know where my new FPR was set. I adjusted it down to 47/48 PSI, still getting pressures inbetween as I slowing adjusted it down.
It WAS holding pressure. Now it will not hold pressure at all. KOEO, it shoots right up to 48-ish, then I hear a click (fuel pump relay?) and it immediately drops to zero. If I KOEO immediately following this, it does nothing. But will do it again if I give it a minute or two.
I've pinched off the return line the best I could (they really dont leave much room where the rubber parts of the lines are) and it still does it. I also pinched off the sending line (also the best I could), and it still does it. Which makes me scratch my head even more, because if I had the send line pinched, it shouldn't have even got initial pressure, right?
Injectors are stock, and fuel pump is stock as far as I'm aware. Both were working great before I did this so I didn't replace either. But now, I'm thinking I "killed" something with that initial spike of 60+ PSI.
Melting Slicks
Joined: May 2003
Posts: 2,078
Likes: 282
From: Dyersburg TN
you did not say so I will assume no visible gas leaking out. if correct pressure at KOEO then quick to zero when pump cuts off it has to have leaked out somewhere. Either past the pump back into tank or past the injectors down into engine. Modern gas is hard on OE injectors and that mega pulse may have been the final blow.
