Feels and sounds like it's out-of-gas

RonzSC

Registered User
Here are the symptoms;

1. Starts O.K. and then as you accelerate, it goes very lean. The valves ping like a champ.

2. As you continue to accelerate, the pinging goes away around 2500 rpm. It bucks like the proverbial bucking bronc when it is in the lean condition.

I have replaced the following;
new factory plugs,
D.I.S.
new hot coil
new camshaft sensor
new crankshaft sensor
new IAC
new Motorcraft battery
cleaned the cold air cleaner filter
brand new gas
new coil pack
new fuel filter

Additionally, I had the gas tank dropped and checked the gas line and it is where a good pick-up should be.

The problem started after I had driven about 2k miles after I did some refreshing of the engine systems.I did remove the blower to get to the valve covers to replace the valve cover gaskets. I spent a significant amount of time checking to avoid vac. leaks.

Am I on the right track by checking the fuel pressure "under load" ? Also, to re-check the I/C sealing areas and the blower sealing areas ?

Your assistance and comments are appreciated.
 
Could be a vacuum leak......:confused:

Are you sure you didn't capture and squeeze the return fuel line when you replaced the fuel filter.....
 
sounds like you may have a vacuum/pressure line off the fuel pressure regulator or the line might be clogged.....................Dan
 
Hmmmm, could be a vac line

sounds like you may have a vacuum/pressure line off the fuel pressure regulator or the line might be clogged.....................Dan

I don't think the fuel line was crimped and I will check that when I put another fuel filter on. Although it ran nicely, for a couple thousand miles.

I like the analysis of the line being of the reg. or the line being clogged. I may have a brittle line and it could have been sloppy when it was re-installed. I can't remember. I know I replaced some 3/8th dia. lines that were borderline brittle.

One other thing that concerns me is that the boost pressure is down. It was running pretty good for having 126k miles.I took the 5% overdrive pulley off after I re-sealed the blower. So I can't tell if the pressure is naturally lower due to the age of the motor and supercharger or a vac leak as described earlier.

Good advice on the line tweak and especially on the re. line.

Thanks
 
When I bought my white 90, the mechanic had replaced the fuel filter.....

He replaced the hose clamp after he installed the little skid pan that protects the fuel filter.....

He ended up clamping the return shut and the engine wouldn't fire because of too much fuel pressure (95 psi)....
 
When I bought my white 90, the mechanic had replaced the fuel filter.....

He replaced the hose clamp after he installed the little skid pan that protects the fuel filter.....

He ended up clamping the return shut and the engine wouldn't fire because of too much fuel pressure (95 psi)....


I am still thinking it could be a vacuum leak somewhere.....
 
Back
Top