I just purchased a 2000 Ford Ranger with 68,000 miles on it. I was told be the pervious owner that it had been sitting for a while. I got it running and replaced Ignition coils, wires, and fresh spark plugs. Replaced MAF sensor, and O2 sensor behind the converter. It idles good. When driving it runs rough whenever I am trying to maintaim speed. If I add more gas it runs fine, if I slow down it runs fine, but if I try to maintinan speed it runs rough. Any suggestions???

Buy a code scanner and try to catch pending codes. This can take out a lot of the guess work and save you a ton of money in the long run... hell, in the short run too!

So you didn't replace the front O2 sensor, just the back one, is that correct? Note that the back O2 sensor does not feed back to the ecu, it's more or less a dummy light.

Curious. Why did you replace the coils, and how much did they cost?

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I replaced the coils because Hanyes Manual recommended a complete tune up including replacing the coils. It cost $102 for the parts, as it is 2 coils, and about 15 mins in time. For some reason it has 8 spark plugs.

Yes I only replaced the rear O2 because it through a code, according to the guys at advance.

Maybe check to make sure throttle body & intake gaskets aren't sucking in extra air. People say starting fluid is good to spray on gasket areas to check. And maybe one of your spark plugs are loosened?

Otherwise maybe partial plug in injecter, maybe try a can of seafoam?

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current - 2001 2.5 5spd 3.73 XLT reg cab short box 165K
dead - 2001 2.3 5spd 3.73 XLT reg cab short box 70K

Offy, what is Seafoam?

Its a cleaner that has a good reputation behind it. All auto part stores stock it.

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current - 2001 2.5 5spd 3.73 XLT reg cab short box 165K
dead - 2001 2.3 5spd 3.73 XLT reg cab short box 70K

and considered snakeoil by some. Might as well tell both sides. Please don't derail the thread with Seafoam stories. Start your own thread if that is your wish.

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That is true. But since it has sat for some years the gas could have turned and left green deposits and it is a cheap/easy alternative that may help the issue. He asked for help so I made my suggestions and said he could try it. I certianly have no personal gains from people purchasing seafoam or like products so wesley can make that call himself.

When I said it was a cleaner I lied about that also, it claims other benefits such as a gas stabalizer, etc. You can read reviews from frf members here: http://www.fordrangerforum.com/gener...ally-work.html

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current - 2001 2.5 5spd 3.73 XLT reg cab short box 165K
dead - 2001 2.3 5spd 3.73 XLT reg cab short box 70K

Code reader a great idea.

You could be having a TPS issue or a clogged orifice in the Throttlebody that is needed for part throttle operation. Putting Seafoam or any other gas treatment/cleaner might dislodge clog. I have used Seafoam in a S10 Blazer I had and it cleaned up the fuel system and I got a little better fuel mileage with that tankful.

I dont think its the fuel lines, as my brother in law and I replaced them, along with the fuel pump, fuel rail, and cleaned the injectors. I am going to replace the forward o2 sensor tonight and hope that works. Someone told me my drive train may be unbalanced?? What do you guys think? This is my first truck so I dont know all the in's and out's.

Wesley, invest in a code scanner, unless you prefer changing out random expensive parts hoping eventually you'll change the right one. Last time I'll suggest it. If you have access to an Android phone or tablet, the "ELM 327 Bluetooth OBD2 scan tool" is like $25 and a popular item.

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If its in the drivetrain the code scanner won't pick-up a code but I agree that it is a very good tool to have for future use. Try going under the truck and shake the driveshaft. It shouldn't be able to move, if it does your probably looking at replacing (hanger bearing if it has one on the driveshaft but I don't think rangers ever had them) or u-joints but they would have to be really bad shape to cause an issue like that.

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current - 2001 2.5 5spd 3.73 XLT reg cab short box 165K
dead - 2001 2.3 5spd 3.73 XLT reg cab short box 70K

I see you have changed out a whole bunch of parts and still have the same issue, I dont see any mention of changing the fuel filter, or whether or not you have added "dry gas" to the gas tank. Because the truck sat for a while, chances are the gas tank has water in it and will cause the symptoms you are complaining about.

Like the others said you should buy a scan tool to prevent from buying unnecissary parts. Hope this helps

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'95 Yellow 2.3 liter, 5 speed manual Splash Edition
'11 Mustang 5.0, 3.73's, 6 MT, Hushpower axle-backs, Eibach Pro springs, CDC Center Fog Grille

When I purchased the truck It wouldnt start seemed like it wasnt getting gas. So I replaced the fuel lines and fule rail, also added a fuel pump and filter. Only after that would it start. I did buy a Bluetooth OBD II reader today.
I have never heard of Dry Gas, what exactly is that and where would I find it?

are you replacing these parts with oem motorcraft parts?

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