Need a little tech help with my 91 ranger 2.3 86,000 miles
I just got it running after it sat for a couple years I've replaced fuel pump and filter after removing tank and cleaning it out. Replaced fuel injectors sea foamed the fuel system and engine.replaced clutch etc. It ran great for a few days and then it started hesitating and sputtering I would be pressing the gas pedal and it would act like it wasn't getting fuel but I would back off the pedal it would keep building speed slowly. But if I pull over shut it down and restart it and it's fine for a few miles then do it again.I have checked all the vac hoses changed the air filter cleaned the throttle. I can not figure out what is causing this iissue.I'm thinking it has to be electrical since it seems fine after I shut it down and restart it. Or maybe the catalytic converter? I'm confused anyone have a clue?

 

I would check or change the fuel filter again, could have got plugged with stuff still in the line.
Or check fuel pressure while holding engine at 2,000RPMs

Yes, quite possible the exhaust is getting a build up of back pressure.
You can test for that with a vacuum gauge or you can remove the down pipe from exhaust manifold and see if engine revs OK
You can sometimes tell by having some one rev the engine while you feel the out flow at the tail pipe, if RPMs are increasing but tailpipe flow doesn't you found the issue.


Most electrical parts are ON/OFF, if engine was dieing outright electrical might be the issue, the limited or slow RPM reads more like a flow issue, in flow or out flow.

 

I thought about the filter going to replace it again I forgot to mention that I also replaced all plugs and wires.my temperature gauge doesn't work. I heard that could cause an issue with the fuel mixture not sure though.

 

No, not the temp gauge, it is hooked to a 1 wire sender that is just used for the drivers info, find the 1 wire sender, remove the connector, turn key on, ground that 1 wire, gauge needle should go to full Hot, if that happens then replace the sender, if it doesn't happen then there is a wiring or gauge issue.

There is a 2 wire Sensor that looks similar to the sender, it is used only by the computer.
It is called the ECT(engine coolant temp) sensor.
Yes, computer does use this sensor to set a Rich fuel mix when engine is cold, like the choke plate did on a carb engine.
When you cold start the engine the idle should be about 1,100rpms, then as engine warms up the idle should start to drop with coolant temp going up.
When engine is fully warmed up, above 1/3 and below 1/2 on gauge, the "target idle" should be set, 700 for manual, 800 for automatic.

If the above happens the ECT sensor is working.
If ECT is not working you could have cold start and running issues when cold, or poor MPG if computer thinks engine is cold all the time, it wouldn't cause your current described symptoms, and computer monitors ECT sensor so it would turn on the Check Engine Light(CEL) if sensor wasn't changing when engine was running.

 

I changed the fuel filter again I also replaced the fuel pressure regulator and it didn't help still having the same issue. replaced the temperature sensor it's working now. I'm not sure what to do next.

 

And the exhaust system?

You can test that with a vacuum meter, under $25, and a nice tool to have.

 

Tank had trash in it most likely from the sea foam cleaning my fuel pump would such it up and truck would start acting start spitting and sputtering I would shut it down and debri would fall back down until sucked it up again would fall Down. I cleaned the tank out again and it running like a champ. I didn't have to pull the tank this time since I cut out a access panel in the bed above the tank.

 

Hey, good work on finding that, and thanks for posting the final fix.