99 Ford Explorer Sport 4.0L. CHUGGING and POOR GAS MILEAGE.

[melsten]

If ANYONE can help I have this truck that is getting terrible gas mileage. About 9 miles per gallon and was chugging all the time. Also I couldn't get up to speed very fast. The engine just wouldn't go. We have already done a few things to the truck.
We replaced all spark plugs, air filter, oil and filter, O2 sensor and today did the IV with seafom.
Now I have the pick up and go but just checked the gas mileage and its still terrible and is chugging when maintaining a certain speed.
Please give me ANY advise you have on these issues. I just left the garage and they told me to replace the spark plug wires, the tps and run mass air flow cleaner through it.
Does anyone think these might help?

 

[vroomzoomboom]

couple of things. do you have a lot of black sut, or is the exhaust color really black? how is the temperature, does it also seem to run cold, with minimal heat? i would start by seeing if you have a vacuum line off at the fuel pressure regulator, or see how much fuel pressure you have at idol, and when the truck is not running. you possibly might have a bad fuel pressure regulator.

 

[BrooklynBay]

Welcome to this forum! I've moved your thread into the stock 95-01 section. Clean the mass air flow sensor.

 

[Keeper0311]

Fuel filter?

 

[nostopin]

mine has the same problem, but it didnt start untill after i put a thermostat in it and it started getting up to operating temp. It san cold for a couple months, now that it is getting warm it runs like crap. Have you done any work to the cooling system?

 

[Jeremy71655]

I have a 97 sport with a 4.0 SOHC that is doing the same thing! I have crawled and crawled threads to see what can be done and it seems that this is a common problem with this motor. So far I have replaced the MAF, TPS, plugs, wires, coil pack and fuel filter. I went to O'riellys this morning and ordered a Speed sensor because one thread suggested that it could be a problem as well. The only thing is the sensor I picked up was completely different than the one that was in my X, and wouldnt fit. After taking it back, we looked for over an hour online and could not find one that matched mine. Im kinda curious if the original had been replaced or redesigned due to this problem. Tommorow I am planning on draining the oil to check for cassette damage, as another thread said that that could be a problem too! I am getting fustrated with this thing! The only codes i am getting is a low voltage indicator for the TPS, and an epc solenoid failure. Any help would be greatly appreciated:

 

[2000StreetRod]

fix the TPS first

I have a 97 sport with a 4.0 SOHC that is doing the same thing! I have crawled and crawled threads to see what can be done and it seems that this is a common problem with this motor. So far I have replaced the MAF, TPS, plugs, wires, coil pack and fuel filter. I went to O'riellys this morning and ordered a Speed sensor because one thread suggested that it could be a problem as well. The only thing is the sensor I picked up was completely different than the one that was in my X, and wouldnt fit. After taking it back, we looked for over an hour online and could not find one that matched mine. Im kinda curious if the original had been replaced or redesigned due to this problem. Tommorow I am planning on draining the oil to check for cassette damage, as another thread said that that could be a problem too! I am getting fustrated with this thing! The only codes i am getting is a low voltage indicator for the TPS, and an epc solenoid failure. Any help would be greatly appreciated:

I suggest that you eliminate your TPS DTC before investigating the timing chains. You don't have to be an elite member to start your own thread.