2000 ranger 4.0 been sputtering,noticeable at idle. Had a PO141 code so I changed O2 sensor, plugs ,and plug wires and cleared the codes..Still sputtering the same. I took carb cleaner to check for any vaccum leaks and found none.And it is NOT throwing any codes as to why the miss Any ideas gents?

 

Maybe try cleaning your MAF, changing fuel filter, air filter.

 

will give that a shot in the morning and let you know how it goes...Thanks!

 

Well cleaned MAF sensor and changed other filters. Still sputtering.... more ideas? Again No codes

 

My truck (even though it is a 2.5L) was showing very similar symptoms and it turned out to be one of the fuel injectors gone bad.

I also did the same thing as you. I checked the fuel filter, the fuel pump, the MAF, etc.

If you checked everything you said you did, I'd try check out your injectors.

 

I also had a bad sputtering that couldn't locate for a long time. Ended up being my spark plugs. Don't know if your truck is the same but mine will ONLY work with Motorcraft plugs that are correctly gapped.

 

yeah I used autolite plugs...man...I guess I'll give motorcraft a try

 

I'm worried it may be injectors...gah I sure hope not

 

Honeywell owns Autolite and the autolite factory in Ohio makes motorcraft spark plugs so they are fine to use if motorcraft aren't available, but they are not the same as motorcraft.

OEM factories build parts to the specifications of the company that orders the parts, in the case of Motorcraft they are built to Ford specs, Autolite may choose to use the same specs, if they are allowed too, or alter them because of cost or.........??
And because of Fords coil pack and waste spark system no matter what brand you use it should be Double Platinum if you want them to last.



P0141 Ford - O2 Heater Circuit Bank 1 Sensor 2
Sensor 2 is the sensor behind the Cat converter, and P0141 usually means a wire is bad or fuse is blown.
O2 sensor has 4 wires, 2 are for computer and 2 for the heater circuit which is fused in engine bay fuse box.
O2 sensors are heated so they can be used sooner, they need to be above 600degF to read oxygen levels.
Sensor 2 is used to monitor if the Cat Converter is working, it isn't used in trimming air:fuel ratios, so won't effect engine operation.

Sensor 1's are near the engine, "upstream sensors", these are used for air:fuel trims.


Does it run OK at higher speeds, RPMs?
If not check fuel pressure, should be 65-70psi on a '00 Ranger when running, increase RPM to approx. 2,000rpms and hold it there while watching fuel pressure, it should stay above 60psi.
Shut off engine and watch pressure, it should hold above 55psi........basically forever.
If pressure starts to drop then you could have leaking injector or bad fuel pump check valve.

After engine is warmed up, unplug IAC(idle air control) valve, it will close and idle should drop to 500rpms or engine may even stall, either is good because that means no vacuum leaks.

If idle stays above 700rpms then you have a vacuum leak.

Double check firing order on coil pack, I mess that up every now and then, either at the coil or at the spark plugs
3 4
2 6
1 5
Front

I know you know it is correct, so did I every time it wasn't, lol.
So trace each wire from coil to spark plug.

 

Yeah it runs ok at higher speeds I can occasionally feel a little buck, I changed sparkpug wires one at a time so I think I'm ok there..I'll check fuel pressure and the IAC and get back to ya ...Thanks for the input so far!!

 

Ok cleaned the IAC valve. . Still sputtering ugh

 

Ran a scan KOEO and got P1000 code and ran KOER and got P1000 and P1127 codes does this help?

 

Ok guys I am at my wits end with this truck! I have changed plugs and plug wires. New O2 sensors new fuel filter air filter cleaned MAF sensor cleaned the AIC valve unplugged it and it died.Ran an entire can of Seafoam at 1/4 of gas through it. I tried a used coil pack and it is STILL missing and sputtering. Ran diagnostics and NO CODES...what else could it be? HELP!!!!!!!!:frown

 

I'm still gonna say it is a fuel injector.

 

I guess that's next

 

The only reason I say that is because I also checked almost everything you did and I had very similar symptoms despite being a 2.5L

It might only be one of them going bad.

Does the truck feel like it is running on one less cylinder? Does it feel underpowered when you start to accelerate?

 

no it isn't missing like it would with a cylinder down...just sputters like it's not missing all the time...the CPU isn't detecting a miss..not really underpowered feeling..but it does buck sometimes but I can give it hard acceleration and it will quit....Man it's driving me NUTS

 

Damn man. Sorry about your luck. Post up what it was when you find out. I'm very curious as to what your gremlin is.

Maybe an injector is just clogged up?

Best of luck.

 

Would you be able to measure your vacuum at idle and let me know what the reading is?

Thanks, Mike

(hope I did not miss this somewhere in your posts)

 

This might be a shot in the dark but try some seafoam in the gas tank and in the oil and also the brake booster

 

what gap are the spark plugs at

ford mechanic said to gap no larger than .054

 

My 97 ranger 4.0 auto trans was doing the VERY SAME thing and I done the same things that you did . I then changed the crank sensor and the problem was gone !

 

Check for air leaks anywhere along the air intake system.
This will effect the MAF sensor signals to the ECM.
May not be your problem but it is always nice to check the easy things first.
Had a problem similar to yours with a Ford Escape, then I noticed that the air filter cover latches were loose. Even this upset the MAF signals.

Mike