• Welcome Visitor! Please take a few seconds and Register for our forum. Even if you don't want to post, you can still 'Like' and react to posts.

MPG off


masanders

Well-Known Member
Joined
May 16, 2016
Messages
218
City
Greenville, SC
Vehicle Year
2000
Engine
2.5 (4 Cylinder)
Transmission
Manual
Tire Size
235/75/15
My credo
Don't get louder, improve your argument.
I just revived my dad's 00 ranger and it is a blast to drive. The only real problem I'm having right now is the gas mileage is about 17mpg when it should be higher around 22mpg. It has new spark plugs, one new injector, new fuel pump, new coils and has had injector cleaner ran through it a lot since it first started up. Not sure what else to do. I'm not driving with a lead foot or doing the one wheel peel.

Any suggestions?

2000 Ranger XLT 2.5 MT 4x2
 
Any check engine light on? Could be a vacuum leak. Unmetered air makes the computer compensate with more gas. It will usually throw a lean code. Does the exhaust smell like unburnt fuel or come out black?
 
Could be a lot of things. Dirty MAF, failing 02 sensor, dirty throttle body, clogged fuel filter, clogged air filter, vacuum leak, low compression, dragging brakes, poor ground connections. and the list goes on and on. If you have not changed the air and fuel filter since getting the truck back on the road do it asap. Especially for the amount of time it was sitting. Also did you replace four or eight spark plugs.

1.Clean MAF with approved cleaner (not carb cleaner) this is cheap easy and could be the issue.

2.Use a vacuum gauge and test vacuum at idle and 2500 rpms. You should have around 18hg at idle

3.Check fuel pressure. You should have 40 psi with the key on and engine off and 32 psi or more at idle.

4. Check engine compression. It should be above 160 psi on a 2.5L

And you are correct with your set up I wouldn't be surprised if you got 26+ mpg on the highway.
 
Just took a quick look and didn't find any vacuum leaks (yet), no CEL, exhaust doesn't smell funny or come out black. The only thing that my scan tool indicated is the fuel trim is around -3 to -6. O2 sensor voltages are all over the place. I'll be getting a vacuum/fuel pressure gauge/tester after payday.

2000 Ranger XLT 2.5 MT 4x2
 
Lots of time miner vacuum leaks or a 02 sensor that is on its way out will not throw a code until the system can no longer compensate for it or it is so far out of tolerance the ECU knows it way off.

Just a heads up. But most parts stores have loaner tools for free. You put down the cost of the tool and get it all back when you return it. If you are short on cash this might help save you a few bucks.
 
Was doing more investigating with my scan tool tonight and everything looked about the same. Then I started to think about the processes I had to go through putting the intake manifold back on after replacing plugs and one injector. I remembered having issues with the pcv valve area. Sure enough when I shone my flashlight at that area, the entire pcv valve was out of the crankcase. I put it back in, took negative battery cable off, and waited. Once everything was reconnected the short term fuel trim seemed to not be as erratic and stayed between +/- 2.3%. Note: I didn't leave the pcv unplugged on purpose.

Bottom line question...Would having the pcv valve off like that have caused the issue I've been talking about?

2000 Ranger XLT 2.5 MT 4x2
 
PCV off ... leaks big time ... to affect one cylinder more than the others... creates a flaky exhaust gas for the O2 to read for excess/lack of unburned O2's... misfire==extra O2s==lean... so it adds gas .. to ALL cylinders where just one was being fed the lean mix. OR some similar explanation will work.
Betchur mpg goes up again as the computer can now adjust for all cylinders cooking along.
tom
 
Yes PCV valve can be a huge vacuum leak. On my 93 I found it off not to long after I got the truck and it would struggle to go up long hills even in 3rd gear.
 
If anybody still follows this thread I wanted to give an update: gas mileage is getting better!
77ddead81f733cf635819456ec2f81c3.png



2000 Ranger XLT 2.5 4x2 MT
 

Sponsored Ad


Sponsored Ad

TRS Events

Member & Vendor Upgrades

For a small yearly donation, you can support this forum and receive a 'Supporting Member' banner, or become a 'Supporting Vendor' and promote your products here. Click the banner to find out how.

Recently Featured

Want to see your truck here? Share your photos and details in the forum.

Ranger Adventure Video

TRS Merchandise

Follow TRS On Instagram

TRS Sponsors


Sponsored Ad


Sponsored Ad


Amazon Deals

Sponsored Ad

Back
Top