Posted: 4/3/2003 8:37:05 PM EDT
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A bit of a question about my vehicle (94 Ford Explorer, 100K+ miles, Fuel Injected 4.0L Engine): Stalled out a week ago, started after a couple of minutes--my initial thought was I stalled it myself by trying to start at a stop light in 3rd gear, and flooded it, so I didn't think much about it, just filled the tank (it was about 1/8th of a tank at the time) and forgot about it. Today, drove about 5 miles in city driving. Parked the car for about 20 minutes, came out and started it. It caught, ran ROUGH at about 300rpms (instead of the normal 800 at warm idle), pushing the gas pedal repeatedly did nothing (no change in idle at all). Stalled. After trying to start for 10 minutes off and on, it started and ran fine, as if there were no problems. Drove the 5 miles back home in start/stop traffic with no problems at all. Went back out to the car about an hour and a half later, and the damn thing wouldn't start again. Cranks fine, just didn't seem to be getting gas. I tried a couple of things in the parking lot--disconnecting the fuel pump cutoff inertia switch and turning it over, checking under the hood for loose vacuum hoses, etc. I couldn't hear the fuel pump whining, but the parking lot is very noisy, so there could have easily been noise without my hearing it. I pulled the fuel pump fuse (was fine) and the Fuel Pump Relay, and it started fine after I plugged them both in back in. I went out and bought a new fuel pump relay (a sticking relay?). I am at a bit of a loss--the car runs fine, good strong accelleration etc. when it is running, at idle it is perfectly fine (smooth 800 rpm idle), no problems with poor gas mileage, has new (<5 months) plugs and wires, a new fuel filter, and runs good gas. I did add a bottle of Alcohol (Gas Line dryer/antifreeze) just in case some water had gotten into the gas tank. The weather is not warm enough to have a vapor lock (it was about 45-50 degrees today). No Check Engine light came on either during the problems. My first thought was the fuel pump went out--but it runs fine AFTER it finally starts, and, I was under the impression that fuel pumps are pretty much On (works fine) or Off (broken and permanantly dead), not intermittent like this. The pump is an in-tank unit, so it is not something easily (or cheaply) changed out to see if that is the problem--I'd rather get a good idea of the problem before I take it to someone for service. Thanks for any ideas!! AFARR |
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next time it happens go to gas tank and listen for the fuel pump to see if it comes on.had a 94 ranger do pretty much the same thing and the fuel pump was not coming on.had it towed home and it started right up.never replaced it started having transmission/rear end problems so i got a new truck.but listen for the pump when you turn the switch on but not to turn it all the way to start. |
| I work on cars for a living - though not Fords. It sounds like either the crankshaft position sensor or mass air flow sensor is starting to go out. Sometimes when a sensor is failing it happens in such a way as it won't trip the check engine light. But it may still set a code in the ECM's self diagnostic memory. Might have your mechanic see if he can pull a code. |
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Sounds like maybe an air/fuel sensor! Don't know as my only truck is carbed. After back reading I see you have replaced filter,maybe injector probs. Just adding the fuel treatments may not do the job if it is the injectors,they make a kit where you more or less disconect the fuel lines to the injectors and run the cleaners right through the injectors! Some one will be by shortly with the right way to do it! Sorry if I can't be of more help! Bob [:D] |
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Not sure if this is what you're seeing, but 4.0L Explorers had a widespread problem with leaking intake manifold gaskets – as the leak got worse, the idle and low-speed drivability suffered, due to leaning out the fuel mixture. (At higher speeds, the engine was taking in enough air anyway to not result in any noticeable loss of power.) Two other items to check would be the cold start sensor (if your vehicle has one) and the throttle posistion sensor (may be noisy or intermittent). |