2.3L ('83-'97) 96 2.3 misfire I cant diagnos

[Geddes84]

Hi everybody! I'm new here but, ofcourse I've read lots of posts helping me solve my problems here through Google searches for many years.
I'm having a misfire issue with my ranger.. I've done all the basic things, plugs, wires and I was giving up on it being electrical until recently hooked my timing light to give it a shot. So with that it was apparent I was having a random misfire from every plug wire. Oddly tho, the misfire will clear up when i take the wire off of the coil and let the arc jump for a distance this happens with every plug wire. I've checked my coils and both primary and secondary resistance is in spec. I'm swapped plug wires, coils, and computer with ones that worked fine from my previous ranger now parts car that ran great when I stopped driving it.. Nothing changes the issue.
The symptoms are. It will miss slight at idle which I'm pretty sure it has always done, but more recently and more of an obvious issue it will noticeably misfire after I accelerate then let off the gas without accelerating, like when I'm shifting and getting up to speed, this miss doesnt carry on forever it will clear itself upon a few seconds. It doesnt seem to miss under load. Also if I rev the engine up and let it go back down to idle it will stumble and die.
I guess this could be a compound issue but I'm not sure. Im really stumped as to what would make the misfire apparent through the timing light only to correct itself when I lengthen the arc between the coil and wire.. Anyone have any pointers? Thanks you guys

I almost forgot, no codes...

 

[alwaysFlOoReD]

What do you have the spark plugs gapped at? Maybe open the gap up a bit?

 

[Geddes84]

I didn't check the gap. They are fresh motorcraft tho, I looked at them and they looked like they were where they should be. I dont think that is it, I recently changed the plugs with no change in the issue. I know gapping is important, I use to do it but I've given up doing it on anything that isnt a small engine like my motorcycle or chainsaw, I've never had it give me an issue, doing it or not. I'll give it a shot tho, I just don't think they are that out of spec from the box. Thanks

 

[Geddes84]

I had time with the ranger today and looked into the injectors. I put my timing light on cylinder one and it had a noticeable misfire, I then unplugged the injector for that cylinder and the flashing of the light didn't indicate a misfire anymore....
I'm cleaning the injectors from my other truck now and I'll install them tomorrow they all seem fine.
Problem in my mind is, I also uninstalled the injectors from my current ranger and they seem fine too (pass cleaner fine, healthy clicking, resistance is within spec)
So I hope these known working ones make a difference but, I'm beginning to think they wont.. pressure regulator possibly? The vehicle seemes like its getting too much fuel, not running lean..I haven't checked pressure but, I'm interested now.

 

[Flounderguts]

Seems like this is a pretty common problem on the 2.3. Mine also misses a bit, or stalls if I run it hard and then let off the pedal fast.

My guess is the HLA system on the rocker arms is getting pressurized with oil, and then keeping the exhaust valves open a bit too much...esp on a higher mileage motor that might have worn/recessed exhaust valves. I'm going to try running a lower viscosity oil and see if it helps.

 

[alwaysFlOoReD]

Seems like this is a pretty common problem on the 2.3. Mine also misses a bit, or stalls if I run it hard and then let off the pedal fast.

My guess is the HLA system on the rocker arms is getting pressurized with oil, and then keeping the exhaust valves open a bit too much...esp on a higher mileage motor that might have worn/recessed exhaust valves. I'm going to try running a lower viscosity oil and see if it helps.

"HLA system"
What is?

 

[Flounderguts]

Hydraulic Lift Adjustment

There are oil filled lifters on the end of the rocker arm opposite the valve. They fill up with oil and automatically adjust the valve lash. Way cool, after you've spent hours and hours adjusting valves on your 22RE Toyota...

 

[Geddes84]

Seems like this is a pretty common problem on the 2.3. Mine also misses a bit, or stalls if I run it hard and then let off the pedal fast.

My guess is the HLA system on the rocker arms is getting pressurized with oil, and then keeping the exhaust valves open a bit too much...esp on a higher mileage motor that might have worn/recessed exhaust valves. I'm going to try running a lower viscosity oil and see if it helps.

Hey, thanks for replying. I've been going back and forth with a fellow over at the ford truck forum for a while now. Very knowledgable guy but I still haven't gotten anywhere with my issue. Randomly one evening I ran across a YouTube video where a guy was having basically the same exact issue I explained and it turned out to be receding valve seats.. So taking that into consideration I was also thinking maybe it's the Hydraulic lash adjusters. I have not tested for this at all yet, but I plan on it soon when I get some time. I'll post the video when I have a chance. I really think this could help a lot of other people. I'll do what I can to keep this updated with my findings.

 

[Geddes84]

That's the video I ran across.

 

[scoutaddiction]

Did you come up with a solution?

 

[scoutaddiction]

I know it's an old thread, I'm currently fighting a similar issue on a 1997 2.3l. Very intermittent misfire on cylinder 4 but I think it's only logging about a 10'th of the misfires it's experiencing. The computers on these old trucks aren't very smart.
Basic troubleshooting with a vacuum gauge indicates that it intermittently has a sticky valve or broken valve spring. My next step is to get it to misfire, shut it down and immediately check compression. It currently takes less than a minute of idling to clean itself out and stop misfiring. Some reason I get all the weird ones, lol

 

[scoutaddiction]

Ok, i verified compression was ok when it was not misfiring, i then ran it at 3000 rpm for about 10 seconds, dropped off the throttle and it was missing as usual. I quickly installed a compression gauge on #4 and verified i had minimal compression pressure, about 25 psi. I then let it sit about 5 minutes without touching anything then checked compression pressure, back to normal 150+. This verified this is a HLA problem. The first thing I'm going to do is try some Seafoam. Previous mechanic replaced the head, lifters and who knows what else. I'll post my results ASAP.

 

[Shran]

@scoutaddiction read through this thread: https://www.therangerstation.com/forums/index.php?threads/1990-2-3-odd-misfire-issues-new-engine.201461/

and watch this video series:

Dunno if your issues are the same as his and many other people's (including mine) that all seem to originate with recent head work. The head gets machined, valve seats are cut in, valve sits deeper in the head than it used to, and the lifters keep the valves open slightly when they should be closed under high oil pressure because the valve stem wasn't shortened to compensate for the recessed valve.

I just learned to live with it. I wanted to replace the lifters with these just to see if it helps, one of the reviews mentioned something similar and apparently it was an improvement:

High Performance 2.3 Ford Hydraulic Lifters

Get the most power from your 2.3 Ford with these anti-pump up hydraulic lifters.

www.speedwaymotors.com

I have never got around to it because in my case it goes away for the most part when the engine warms up. Easy & cheap to swap those out, lot easier than pulling the head.