My 1993 Jeep Wrangler has been down for a bit

ANONYMOUS

MEMBER
1993 JEEP WRANGLER
150,000 MILES

My 1993 Jeep Wrangler has been down for a bit. It is the "S" model, with the 2.5l inline 4.

It will turn over, but will not run. If I keep tapping the throttle, it will keep sputtering, but it will not run. I am not getting any fuel out of the Schrader valve, and I can hear the pump prime when the key is turned. I replaced the fuel filter and TPS. Both to no avail. When I am continuously tapping the throttle, I do get a distinct fuel smell, but no fuel to the rail. I am not seeing any leaks from the visible connections, hoses, or lines.

What is the most likely problem? And how can I go about tracking down the problem?

-Jason

1 Reply

CARADIODOC

MECHANIC
33,743 POSTS

Try a new map sensor. The clue is the engine will run well enough to drive it into the shop as long as the gas pedal is moving. It will stall when you hold the pedal steady in any position. You may not get a diagnostic fault code for it either. It is fed with 5.0 volts, and the acceptable signal voltage is between 0.5 and 4.5 volts. The sensor can report the wrong voltage when it begins to fail, and that will cause miserable running problems, but as long as that incorrect voltage stays within that acceptable range, no code will be set.

Check the vacuum hose going to it too for cracks and leaks.