Hello all, I just bought a 99 Ranger 3.0 L. Truck runs great while cold. After it warms up however it has a misfire. I knew that when I bought it, and bought it cheap enough that I figured even if its down on compression or something serious, I could afford to throw a long block in it. It also is throwing a check engine light. I have not read the codes yet, waiting on a scanner I purchased. Ive got new plugs and wires for it, not yet installed. Also, have not checked compression yet. Been too busy to work on it much so far. Just curious if there is anything I can look at before the new scanner arrives. In other words, anyone else had this issue? What did you find? TIA

 

I've got a '98 3.0 Ranger that I've had less than a year. It was owned by my cousin who died and I got it really cheap because his siblings didn't want the thing.
My advice is to buy an OBDII code reader and pull the codes. (As I type this, Amazon has a code reader for ~$15 if you are a prime member) Your local auto parts stores can read the code(s) also.
Since they are cheap, start with spark plugs and possibly new wires. Before you dump a bunch of parts into it, you need to find out what is causing the problem. But if it runs good when cold, I'd be willing to bet the mechanicals of the engine are okay. Find out that the engine is good before dumping more money into maintenance parts.
BTW, my truck was so neglected that it had about six inches of cigarette ashes and butts in it. I had to open both doors on a windy day, park the truck side ways from the wind and I took a three foot air gun to blow all the ashes out. What a cloud I created!
Good luck.

 

Yeah. probably going to run compression on it today. Then install new plugs and wires. I forgot to include that it is mainly misfiring at idle. I'm like you, I don't think there is anything seriously wrong mechanically. I did replace a leaky water pump on it, just hoping that the PO didn't over heat it. No coolant in the oil or steam out the exhaust, so I'm thinking I'm OK there. Worst case scenario, I may have to have the heads reworked if the compression test shows up some bad valve seats. I should have my code scanner Monday. That will be my next step after running compression. It's got 220,000 on it and the rest of the truck is tight and nice. It did have a tree branch fall on the top and hood but that is the least of my worries, Truck appears to have been very well maintained. The guy I bought it from says that the CEL is a O2 sensor code. We shall see. I was a diesel mechanic professionally for over 25 years so none of this is out of my league, just not that familiar with the newer OBD2 stuff. Have owned 2 previous Rangers and 2 previous Explorers but never really had any serious issues with any of them that I couldn't find easily. I will get it figured out, just wondering if anyone had had similar problems and what they found.

 

Just a bit of an update........After running compression on it I found #5cylinder had a misfire code and was at 60 lbs of compression. I added a couple of teaspoons of oil thru the spark plug hole and it came up to 120 lbs. Ok.....Im thinking I must have some broken rings or something on #5 but still had the valve issues that these 3.0's are known for in the back of my mind. Pulled both heads and other than 220,000 miles of normal wear, the cylinders didn't look too bad. No scoring or anything on #5 to indicate broken rings. I turned the heads upside down on the workbench and dumped some diesel fuel in the domes of the heads. They all allowed some leakage past the valves but #5 leaked down quick. I decided since the rest of the truck was in pretty good shape and my wife and I both liked it, to go ahead and just put a long block in it, since it did have 220,000 on it. It should last us a Looooong time now. Pulled the rest of the motor out and then when I swapped the pan I dropped one main and one rod bearing just to see what they looked like, glad I did, I didn't see brass yet, but they weren't too far from it. Also, just looking at the way the inside of the block looked, (crunchy cooked on oil residue) I'm pretty sure it had been hot at some point. Im now in the truck a little over $3000. But doesn't bother me. The long block I put in has a 3 year unlimited mileage full replacement (labor and everything) warranty. I got it all put back in last night and ran it for about 1/2 hour (to break the cam in) in the shop. So far so good......no runs, no drips, no errors, no CEL. Going to put the hood on it this morning and swap some tires around off the old Explorer and drive the **** out of this thing!

 

I wouldn't do too much worrying about camshaft break-in on this engine. It's got roller lifters. About the only thing this engine needs on break-in is the piston rings and if it's got moly rings, it's almost broke in by the time you start it. (Now my 4.0 Jeep that's getting a new engine this week has sliding lifters and it's a different story)
ANYWAY, enjoy your ride and it sounds like you've got all your problems fixed.

 

Sounds like you have a good grip on your Rangers resurrection!!!

 

YEA! another Ranger lives!

 

Running like a top!!!! I only had one small leak and that is where the hose attaches to the bottom of the coolant recovery bottle. I cant tell if it is leaking from the bottle or just the hose. Going to cut the end of the hose off a bit today and see if it quits. If not, I picked up a new bottle from the wrecking yard a couple of days ago. This thing should last me and the wife a long time now, it had a new clutch already in it that I discovered when I had the motor out. The body and interior are in exceptionally good shape for having 220,000 on it (besides the dents in the roof and the hood where the PO told me a tree branch had fallen on it) Steering is tight, 4x4 works .......someone had taken good care of this truck for a long time. This is the 3rd Ranger Ive had; a '91 a '06 I bought new and now this '99. We've also had 2 Explorers, a '91 my wife bought new, and an '01 which the '99 Ranger is replacing. I sold the '91 Ranger to my brother, it now has what we guess to be 350,000 on it, Sold the '91 Explorer to the kids, it went well over 300,000 and now the same brother bought the '01 Explorer for his 16 year old daughter. It currently has 200,000 on it. With some care these things run forever!!!!

 

Just a little update........Had put about 200 miles on it after getting the long block installed. Yesterday, I went out and fired it up to let it warm up and thaw the windows out (it was about 10 degrees that night and fresh snow) The wife and I went to leave in it about 10 minutes later and I noticed antifreeze in the snow. (Dammit) Upon further inspection, I found it was leaking from the radiator where the tanks attach to the core. Off to town in another truck for a radiator......... I had flushed the cooling system prior to deciding I needed to put the longblock in. Just used some off the shelf flush from OReillys. (don't remember what brand, I normally use Permatex but they didn't have any) I don't know if the flush caused it, the radiator that was in it didn't look that old and was definitely an aftermarket rad. I had this exact same thing happen on a '91 Ranger years ago....... flushed it, it held for a few days then started leaking between the tank and core.......guess I wont flush Ranger radiators anymore.....LOL Threw the new rad in and all is well so far!