Still sucking fuel...

[JTH1972]

-Plugs and wires are replaced.
-Air filter replaced
-fuel filter replaced
-PCV valve replaced
-MAF sensor cleaned
-IAF sensor cleaned
-used injector cleaner at least 3 to 4 different times since I bought the vehicle in July
-battery disconnected and cleaned, computer reset.

Still getting around 13 MPG when I used to get around 17 MPG.

Replacing the fuel regulator has been suggested, but my parts guy says they've never had to replace one in any of the Explorers they've worked on. If your experience says otherwise, please say so! Any other advice is appreciated.

 

[Half-cocked]

Sticking brake caliper(s)?

 

[Maniak]

FPR on the explorers do go bad. When they go bad normally they rupture the diphram. When that happens you suck fuel into the vacuum line which goes right into the upper intake. When its severe you actually get fuel into the oil.

Its easy to test FPR. First take the line off the FPR and make sure there is no fuel in there.. Assuming there isn't, hook up a Fuel pressure tester to the schrader valve on the FPR and make sure your getting the 32-38psi.

When our last one went bad we were getting 50psi all the time (with no fuel in the vacuum line). With the 50psi our fuel mileage dropped and it idled like it had a big cam.

~Mark

Edit: I almost forgot. For cleaning the injectors, don't bother with the stuff you drop into the tank. What you want to get done is a motorvac. Its a machine that you connect to the fuel lines and it runs your engine off this cleaner mixed with fuel. The cleaner is strong enough that you can't run it in the tank.

 

[JTH1972]

Idle's been OK on it. Acceleration has been so-so, but I don't punch it anyway.

Thanks for the info on the injectors. I want to get the tranny flushed before winter really hits so I'll look into that too.

 

[merryc3]

I just brought my 94 explorer in for new shocks. I asked my mechanic to check over the truck....mentioned a rattle that sounds like it's coming from under the truck on acceleration....been hearing it for years. My ex-husband told me it was the speedometer cable...duh! starts @45mph to about 55 mph.
My mechanic told me that my air intake hose was in terrible shape and my injectors were filthy. He installed a new hose and cleaned the injectors. The rattle is gone. I hope my gas mileage improves! my mechanic prioritized my repairs. New shocks can wait. Anyway....those gas tank additive cleaners are not powerful enough to really clean the injectors when they're really dirty. I have a good feeling about the service done on my truck today.

 

[JTH1972]

So where can I find the tester to check the fuel pressure? One of my local parts places sells a professional kit for like $200 to $300, and I aint spending that much!

 

[Maniak]

Around here the chain auto parts stores sell them for well under $50.

Basically your looking for this http://www.amazon.com/gp/product/B001R97XFS?ie=UTF8&force-full-site=1

~Mark

 

[JTH1972]

Well, so far the cheapest I've found a tester for locally was $80, and that's just for the gauge. The FPR is going to cost me $108. Hmmm...

I've noticed my temp gauge fluctuating on occasion too. Going from half way (which it rarely sits) to just above the "L", it normally sits just around the "C". I still have to change the thermostat, but it looks like it's going to be a real PITA to change. Thoughts on what could be causing this and will it have an affect on mileage?

I was talking to a parts guy the other day and he said that he's heard of O2 sensors going bad and causing the computer to default to a "rich" setting without throwing a code. Possible too?

Any ideas are appreciated. The full tune up had to be done anyway, but now I'm getting to the point of throwing money at problems without knowing an exact cause.

Edit: My father in law was saying that it sounded like a cylinder is missing when I was driving past him going up hill. I haven't noticed anything myself, but he's got a real acoustically tuned ear, so who knows. Could an injector be bad?

 

[Half-cocked]

I had a misfire in one cylinder last year, but I felt it rather than heard it (felt like the transmission was momentarily dropping out of overdrive). New wires and plugs didn't help, but it cleared up and ran good as new when they replaced one of the coil packs.

But if your temp is fluctuating, it's probably a sticking thermostat. A cold engine doesn't run efficiently. I had to have mine ('99 Mountaineer V8) replaced at about 90K.

 

[JTH1972]

But if your temp is fluctuating, it's probably a sticking thermostat. A cold engine doesn't run efficiently. I had to have mine ('99 Mountaineer V8) replaced at about 90K.

Any tips without having to tear half of the motor apart? There's not a whole lot of room up front.

 

[smcgee1979]

your thermostat shouldn't be that hard to get to. the outlet is right on top next to the alternator. should be 2 bolts.

 

[JTH1972]

I know where it's at, it's just a mater of getting to the two bolts!

 

[MrQ]

your thermostat shouldn't be that hard to get to. the outlet is right on top next to the alternator. should be 2 bolts.

SMC you are running a V8 not a V6. The thermostat housing is located under a AC line which cannot be removed.

JTH, I believe the easiest way to get to it would be to remove the fan shroud. Unfortunately, to completely remove it you have to take out the fan which requires a $20 tool. With it out you should have enough room to get the housing out. Be careful with those bolts though. They can strip since the the timing cover it is bolted to is aluminum

 

[mustangsrus]

pics of this FRP on the V6 4.0`s please !! mine only avg`s 13 MPG

 

[JTH1972]

pics of this FRP on the V6 4.0`s please !! mine only avg`s 13 MPG

I'm having the same issue.

MrQ: Yea, a $20 tool for you guys seems to work itself to around $50 up here! lol (hey, what the hell am I laughing about?!?!?!). I got access to some flex shafts that may do the trick. I was thinking of flushing the system too, but there's two lines that "T" into one line that goes to the heater core (and not much space on that line) so I'm not sure which one I would install the flushing kit on to.

About the O2 sensors, I've had two parts guys tell me that they show only one sensor for the Explorer, but I thought I saw two under there?

 

[MrQ]

Whoops, I didn't see that you lived in maple leaf territory.

IIRC, 91-92 explorers only had one O2 sensor. 93-94 had two. As for the flush check this thread out here. It might be able to answer your questions.

 

[Maniak]

Lets see if I can kill 2 birds with 1 stone here..

Here is a pic I found on EF which shows how/where the thermostat is (and why its a paint to take out) and the FPR.

You can see the FPR just up and left of the thermostat. It has a braided line on the top of it.

As for pulling the thermostat. It is easier if you pull/move the fan shroud. I use a 1/4 ratchet with a an extension. When I'm putting the bolts back in I put a dab of RTV in the socket to hold the bold as I put the bolt back in.

Also, 1991 and 1992 STOCK A/c lines ran around the back of the motor. If they were ever replaced they would be in front, under the TB just like it is on the '93 and 94.

~Mark

 

[JTH1972]

Got the thermostat changed (what a PITA that was!) but the same results. Gauge dropping to just the right side of the "C" from around the "N" in "normal". With the truck in park and the needle on the "N", I reved the motor to 2000 RPM and watched the needle drop to just before the "C". Huh?

The thermostat I put in was rated for 195F. So what could it be now? Coolant sensor?

 

[huntman58]

On my 93 with the factory tow package that is about were mine runs also. That seams to almost be normal with the auto tranny tow package when it is a bit cold out side as it seams to be getting now days in your area. I know it is warmer here (in the 70's) and I run about the N on Normal during the day but hard pressed to even hit the N at night or evening time (temps are in the high 50's). Then it’s between the C and the N
Hope that helps you a bit

 

[shaggymane]

Got the thermostat changed (what a PITA that was!) but the same results. Gauge dropping to just the right side of the "C" from around the "N" in "normal". With the truck in park and the needle on the "N", I reved the motor to 2000 RPM and watched the needle drop to just before the "C". Huh?

The thermostat I put in was rated for 195F. So what could it be now? Coolant sensor?

those sending units do weird things when they go bad. Talk about *huh?* Mine suddenly started pegging the gauge all the way to the right as soon as the engine was running. As the motor warmed up it would move to the center.

Harbor Freight sells Fuel pressure testers for about $10 bux when they are on sale. I paid $40 at O Reilly's. With a new FPR my tester shows 28-30psi idling, which should be just a bit too low. They probably aren't the most accurate tools but good enough to show 90psi ....ergo, bad FPR