1990 Ford F150 - 4.9L No Power

[LRAMP]

1990 FORD F-150 PICKUP, 4.9L INLINE 6
TRUCK WAS TOWED IN WITH NO POWER AS SYMPTOM. TRUCK WOULD NOT RUN AT IDLE. OWNER STATED THAT TRUCK HAS SAT IN PASTURE FOR QUITE A WHILE. WE STARTED WITH THE FACT THAT THE FUEL WAS VARNISH. WE CLEANED THE TANK, REPLACED FUEL FILTERS, FLUSHED THE LINE AND CLEANED THE INJECTORS.FUEL PRESSURE IS AT SPEC. PLUGS WERE FOULED AND WERE REPLACED. IGNITION CONTROL MODULE WAS FOUND CRACKED AND WAS REPLACED. DISTRIBUTOR CAP AND ROTOR WERE REPLACED. REPLACED IAC. ALL VACCUM LINES WERE CHECKED AND REPLACED. CYLINDERS SHOW NO IMBALANCE.

TRUCK WILL START UP NOW AND RUN AT IDLE. WHEN IDLE IS INCREASED, THE ENGINE BOGS DOWN AND HAS NO POWER. IF A VACUUM LEAK IS INDUCED, ENGINE WILL RUN BETTER BUT STILL SLUGGISH. WHEN PUT IN GEAR, ENGINE DIES.

ANY SUGGESTIONS?

LEO RAMP
RAMP AUTOMOTIVE
LAMPASAS, TX

[steven kiser]

critters. check for restrictions in the exhaust and nibbled hoses and wires. i had one that the plenum was plugged with debris from nests. a quickie would be pulling the 02's and seeing what happens.

[brianp87]

Yes checking exhuast for restrictions should be one of the first things

[steven kiser]

i just had a flash, check the wire that has the timing shunt in it. if that's broken the truck will barely run. oh ya, no wise a** remarks about "steve having a flash". i've also run into fords that have sat for a while having all the injectors stick. sounds like a few that i've had.................good luck. if it needs injectors check pricing with "jeggs". i've had great sucess with them for pricing and performance.

[fortknoxx]

flaming fur balls are a sight to see.

[steven kiser]

amen to that.