Hello all, first post here.

I have a 95 Ranger w/ 2.3L, 145,000 miles. Been driving it for a bit over a year and has always had a rough idle. I finally made the time to try to smooth it out. First step was to change the plugs. Well, they had apparently NEVER been changed and one of them broke off in the head.

SO..I pulled the head. Figured it'd be a good chance to look at things, clean up any carbon, etc.

Just got it back together last night and started it. Couldn't run it long because I found that the thermostat housing had a small hole in it (probably from using it for a handle while placing that heavy back on the block!)and started spitting coolant (oh yeah, my exhust manifold didn't seal either...grrrrrrrr ).

I did notice though right away that the idle was still rough, and possibly a bit worse than before. I know that all the throttle body cleaner in there needs to burn out, but thinking that the 2-3 minutes that it ran would've burned it out and idle should've smoothed out if everything was up to par.

It now has new plugs, wires, and PCV (not to mention all gaskets and head bolts).

The CEL did not come on nor has it ever been on since I've owned the truck. I have an ODBII code reader but I believe that 95' is still ODBI???? Would it do me any good to hook this up and check for any pending codes?

I did not clean or replace any sensors. If this looks like a sensor issue, which would be the best to start with? At $50 and up per sensor I sure don't want to go replacing everything if I don't have to.

 

Welcome to FTE!!!

Did you change the plug wires?

I'm sure the other users will have more ideas.

 

Yes. New plugs, plug wires, and PCV valve.....and shortly a new thermostat housing.

 

Try cleaning the MAF. There's loads of threads in here that will tell you how to do that.

 

Thanks Nate, that'll be the first thing I do after I replace the thermostat housing. It's on order, hoping it'll be here for me to work on it this weekend. I'll post any info as I get it.

In the meantime, if anybody else has any ideas I'm all ears (err...eyes actually).

I've read alot about the IAC, although I don't have that howling noise everybody talks about. Is that noise always a symptom of a bad IAC, or only sometimes?

O2 sensors aren't providing any information while the engine is warming up from what I understand. Is that correct?

 

The pcm ignores O2 data until all of the warm up criteria has been met.

I also have a 95 Ranger with the 2.3L. Things I have done are plugs (Platnium plugs), plug wires, ignition coil packs, injector cleaning, fuel filter.

It doesn't hurt to check to see if there is any codes . And it is obd II , I use my shop's genisys scan tool to retrieve my codes, which uses the obd II dlc connector.

Let me know how you make out.

 

Finally received the new thermostat housing at got to it.

The motor is running pretty darn rough, not only at idle but throughout the RPM range.

I cleaned the MAF, and also removed and cleaned the air bypass....which was actually pretty clean to begin with.

I removed the timing belt cover and double checked to make sure that all my timing marks were lined up, which they are.

I pulled the #1 plugs out to look at them (remember, they were brand new). The intake side plug was carboned up more than I expected. The exhust side looked good....just a little bit of black.

Since I don't have a spark tester, I thought I'd see if I could remove wires one at a time and run the engine....each one that made things worse would then be put back on, then test the next one. Well, I started with the intake side coil pack, and removed the #1 wire.....NO CHANGE. Hmmmm. So I then simply removed the wire harness connector from the whole coil pack....no change? Then I put everything back together and removed the harness connector from the other coil pack. Then engine ran, about the same but the CEL did come on right away. From this I concluded that my test wasn't going to work very well because of the fact that there are 2 plugs/cyl.

My next step is to get a spark tester to verify that each and every plug is getting voltage from the coil packs.

If everything looks good there, i'm not sure where to go next? Check compression, injectors?

 

Just moving this thread back to the top....since nobody replied :-(

....any ideas???

 

Check your firing order! Back in January I did just like you did replacing things that go along with a tune up cap, rotor(mine is a 94), pcv, plugs wires, cleaned my k&n, fuel filter, cleaned the MAF, etc. My problem started after I did all this! Long story short my engine would backfire and pop and hesitate when driving in gear(manual tranny)! I got the wires and plugs replaced under warrenty thinging that might have been the problem, but when replaced only made things WORSE even though they all went back together the same way they were taken out. It gave it a hugely rough idle, was still driveable, but horrible to even try and drive. I checked my firing order on my intake and found it to be 142536 (3.0 v6). I had cylinders 2 & 3 backwards! Smoothed it right out, fixed my hesitation/popping/backfiring, and fixed my gas mileage issue!

Good Luck!

 

The idle was never right either from the get go! So yeah this fixed it for me.

 

I will certainly double check the firing order. I don't think it's running bad enough to be that but hey...it's worth a double check.

My big concern right now is, since I had the head off, that something didn't seal right and I am losing compression on a cylinder?? I guess I always expect the worse though.

If I check for compression, what would be the proper way to do so?

 

Double check the all the intake bolts and retorque them again.

 

I picked up one of those induction type spark testers, just so I could be sure that each plug was getting something from the coil. The test did verify this for me.

I also double-checked my firing order/plug wires. Everything is as it should be. Cyl one in front, then two, three, and four in rear.

I went through all of the intake bolts and re-torqued them. All were dead-on except one was able to go about 90 degrees further.

Also, I went ahead and did a compression check.

#1 - 157 PSI
#2 - 165 PSI
#3 - 160 PSI
#4 - 157 PSI

Still runs like crap....idles like it's got a radical cam!



Here's one thing that I'm starting to think about:

 

My cylinders that were reversed weren't in the worst of positions when they fired. Either one or both fired when the exhaust valve was open, hence the popping i was getting! So idle and running wasn't as bad as say if it was trying to fire in the middle of the compression stroke.

 

Is that the twin spark plug engine? Coil Packs? or distributer?

Put a wrench on your crank and watch (with spark plug out and looking through the hole) and see when your piston is at TDC Top Dead Center and see if that plug would fire. I know for an engine like mine with a cap and rotor you make sure that the rotor is pointing at the #1 spot on the cap. Not quite sure how to check with coil packs but someone probly knows in the forum!!!