Really poor fuel mileage

[CHEVTECH]

I have a 94 explorer xlt 4.0l 4x4, after truck hits normal operating temp it begins to flood it self when you try to accelerate wont go above 3k or with bog right out at WOT (wide open throttle) now the engine light does come on when the pcm does its enitial check but still runs fine until warm i havent had the chance to scan it b/c i dont wanna pay lol im a tech at a chev dealer and dont have a multi-scan so is there any posible way to get flash codes from this pcm? and does this vehicle have a history with bad ECT sensors? its giving all the symtoms of running in cold start all the with the lack of power and fuel mileage i figured i give this a try so any common probs with these symtoms let me know its greatly appreicated!

 

[lofton316]

I have a 94 explorer xlt 4.0l 4x4, after truck hits normal operating temp it begins to flood it self when you try to accelerate wont go above 3k or with bog right out at WOT (wide open throttle) now the engine light does come on when the pcm does its enitial check but still runs fine until warm i havent had the chance to scan it b/c i dont wanna pay lol im a tech at a chev dealer and dont have a multi-scan so is there any posible way to get flash codes from this pcm? and does this vehicle have a history with bad ECT sensors? its giving all the symtoms of running in cold start all the with the lack of power and fuel mileage i figured i give this a try so any common probs with these symtoms let me know its greatly appreicated!

replace your pcv value and see what happens

 

[L4CX]

If you have an Autozone around you can go there and they scan it for codes....For FREE! I think that's what you meant by Scan it.

So the real question is why do you own a Ford when you are a Chevy tech? Just curious

:edit: I didn't pay attention to the year. I'm not sure if they can do pre-96 models. You can always try though.

 

[CHEVTECH]

HAHA for some reason everyone asks me that! i smoked the trans in my sierra and you know how mechanics are! i wasnt about to fix it! and i got this from a buddy for a good price and he was in ajamb so it worked out good!

 

[CHEVTECH]

do you know what a PCV is or does or even stands for? that wouldnt cause the problem b/c if the crankcase was pressureizing so much that it would bog the motor the PCV valve would blow out of the rocker cover! and when it bogs down its real hard like you almost hit your head on the wheel! 0-100kmh is probably a solid 45 seconds and its only getting about 5-7 mpg!!

 

[L4CX]

HAHA for some reason everyone asks me that! i smoked the trans in my sierra and you know how mechanics are! i wasnt about to fix it! and i got this from a buddy for a good price and he was in ajamb so it worked out good!

Well, I guess it's good that worked out for ya. A sierra was one of my "dream" trucks when I was in High school. I got an S10 instead. Oh well. The Explorer is better then anything I thought if in High School.

You could try searching the site. It also helps to know if you have the SOHC or OHV Engine. It's the 8th Number in the VIN, X = OHV, E = SOHC. That will help people narrow down what it could be. There are a ton of thread on Both engines. Try a search intill someone with more Knowledge takes a look at this thread. hope they can help.

 

[MrShorty]

All you need to get codes from a '94 is a jumper wire (or paper clip or similar). See the stickies in the EEC-IV forum.

I haven't heard of a lot of ECT failures. ECT is a simple thermistor, and is easily tested with a multimeter. I don't think I'd worry too much about the ECT until you get the DTC's from the computer.

 

[ma96782]

Try some fuel pressure readings.....could be as simple as a faulty FPR (fuel pressure regulator).

There is no code for FPR, but a bad FPR will sometimes set an O2 sensor code.

There are 2 tests you can do on the FPR:

1) Locate the vacuum line that runs from the FPR to the vacuum tree. Disconnect the vac line at the vacuum tree and see if fuel drips out of the hose. If fuel comes out, the diaphgragm in the FPR is blown. This causes fuel to be sucked from the FPR into the intake manifold, resulting in a very rich mixture and poor fuel economy.

2) Get a fuel pressure gauge (cost about $25 or $30) and measure the pressure at the fuel rail test port. Pressure should be about 35 psi, increasing by about 5 psi when the engine is revved or the vacuum line is disconnected. If its much higher FPR is bad. If much lower, could be FPR, clogged fuel filter, or bad fuel pump. Example: When my FPR failed, it was reading 80-90 psi and pulsating. With pressure this high, the computer tried to compensate, resulting in a "too lean" code.

Bwana Bob
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Explorer Fuel Pressure Test

http://www.explorerforum.com/forums/showthread.php?t=142801

Aloha, Mark