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I would imagine that you're missing ONE flash.
That would mean 13 ...MAP sensor ..which would definitely contribute to your mileage problem.
Why am I getting 11mpg?!
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That would mean 13 ...MAP sensor ..which would definitely contribute to your mileage problem.
Good call, try that test again, you could be on to something. If the sensor gives a code, shouldn't it set the Check engine light?
Yes, we do have the bad winter gas, however, the '67 mustang and the '01 dakota in my driveway both with big V8s run on the same gas and get WAY better mileage.
It's got 3.55's, which is standard on all with the automatic transmission.
Yep...that's how I do it.
After doing it about 15 times I can see that it might be 1-2-5-5, but definately not a 13. 12 is battery disconnected within the last 50 key cycles, however, I'm 99.9% sure that it wasn't.
ZmOz, pull off the vacuum line from the fuel pressure regulator and inspect it. If it's damp from fuel, you've found the problem; a ruptured diaphram in the FPR. If it's bad, raw fuel will be drawn into the intake manifold and ruin the MPG.
Okay, I do agree that *something* is wrong, and needs to be corrected. Probably some sensor. Lots and lots can decrease mileage.
Sorry 'bout that.
My 89 Cherokee has the FPR on the forward end of the fuel rail. I guess Jeep changed the location somewhere down the line.....
My 89 Cherokee has the FPR on the forward end of the fuel rail. I guess Jeep changed the location somewhere down the line.....
Yeah, they like to move things around like that so it's easier and cheaper to change.quote:
Originally posted by TheLoneRanger:
Sorry 'bout that.
My 89 Cherokee has the FPR on the forward end of the fuel rail. I guess Jeep changed the location somewhere down the line.....
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Well, you've reached the "limited" limit of the user accessable on board diagnostics. There are many more....
Not necessarily. Only serious emissions or operationally disruptive codes light the CEL.
For example ...as the system fuel system degrades over time (clogged, leaking injectors, weaker fuel, pump, etc.) the PCM registers the incidence of lean or rich conditions while in open loop. That is, although the speed density system doesn't change the pulse width according to the O2 sensor while in open loop ...it records the readings. XXX lean readings ...it effects a "correction" to compensate. These are called adaptive cells. These are only viewable with an OBDII scanner.
There are many others.....
Spend the $40 and get a pro to give you a read out..
Do you have the AW transmission?
ZmOZ I was reading all the posts looking for some mention of the catalytic converter. I see it was replaced before you got the truck. Can you be certain it is the right one? (size, flow characteristics etc.) A buddy of mine was really sad with his '95 F-250. He tows the same holiday trailer as I do and he was getting 6 mpg. After we talked a bit he decided to look at the cat (he's a motorhead and spent all his time looking under the hood). To make a long story even longer, a new cat doubled his gas mileage.
I've finally gone through a tank of gas since I replaced the fuel filter, spark plugs, wires, and distributor cap. I've managed to burn 14 gallons of gas in 162 miles!
What could POSSIBLY be causing this??????? I think all those things I replaced had 200,000 miles on them...and they made NO difference! AHHHHHHHHH!!!
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Are you in an emissions state? You've got to be putting out excessive HC or CO or NOX with that kind of mileage (HC and CO surely). There has got to be a shop that has a Sun Interogator that should be able to pinpoint this problem.
Does your lockup converter engage (it should - THIS DOES generate a code ..too much difference between engine rpm and vss output)
I'd start looking for a pressureized leak. For that matter ..a static one.
Does your lockup converter engage (it should - THIS DOES generate a code ..too much difference between engine rpm and vss output)
I'd start looking for a pressureized leak. For that matter ..a static one.
only if you've got ice cold 600Wt in them.quote:
Originally posted by ZmOz:
Yeah, I've got to get it tested this month actually. I'm going to fail...
What if maybe the wrong weight of gear oil was put in the diffs? Could that make this much of a difference? [/QB]
-Bret
Alright guys, just a little update. I reset the computer after changing the spark plugs didn't help. Mileage went from 11 to 16.5!!!!
I also took a trip up to the mountain yesterday, 170 mile round trip - 25mpg!!!
That's with 3 200lb+ men, 2 dogs, lots of beer, and going up a mountain in 3rd gear!
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See? I told you having a relief tube that drained into the tank would help
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