Recently purchased a 89 2.3 ranger that ran rough. Smoked a fair amount and would not open up without cutting out and dying. And Would only run with map sensor unplugged.

Dissembling engine # 3 cylinder was scored we had the block bored out. 30 thousands Previous owner had thrown a ton of parts at it trying to get a a failed rebuild to run.

engine is back in the truck. will not start or run with all sensors plugged in. But if you unplug the map sensor it fires right up but obviously will not run right the air to fuel mixture is off. Plug the map sensor back in while still running the idle will clean up. I am able to get it to move with more rpm. But has no power it will die without enough rpm when releasing the clutch. Can drive around the yard and thats it.

new coils and plugs, wires.

New map sensor , egr appears to be new “ previous owner”
throttle position sensor new.
water temp sensor new.
crank sensor new.
new fuel pump and filter
New o2 sensors

I am probably missing more parts any help on trying to solve this would be great

 

Welcome to the forum

Gasoline engines need 3 things to run, single cylinder to V12s
1. Spark, at the right time
2. fuel, in the right mix with air
3. compression, spark can't ignite liquid gasoline, it can only ignite gasoline vapor, compression HEATS the gasoline to make it a vapor

How old is the gasoline in the system?
Gasoline only last 4 to 6 months in an "open" container, if its older drain as much as possible and add fresh fuel, 10% ethanol is best to deal with older gasoline
"Open" container in this case means gasoline has contact with alot of air in gas tank, so WILL evaporate and change to a "non-fuel", lol

On the engine is the FPR(fuel pressure regulator), it has the fuel return hose attached AND a Vacuum hose, check the vacuum hose for gasoline, if found replace FPR it's leaking and engine is flooding out

Pull the computer and open it up and have a look at the circuit board, usually problems are easy to see, leaking capacitors are common after 20+ years and under $5 to fix
If computer looks good then you can look at other issues
The computer runs the fuel system

Test compression on 1 or 2 cylinders, 160+ psi is expected if timing belt is aligned correctly, this takes compression off the table

These will take fuel and compression issues off the table

Whats left is Spark
1989-1994 2.3l Rangers used an ICM(ignition control module), it runs the spark system, doesn't need the computer
Crank sensor, ICM and coil packs are the separate spark system
ICMs were a known issue when older

The computer is sent the crank sensor signal to time the injectors
And computer does send the ICM spark advance changes for engine load, like Vacuum Advance on older distributors
But ICM controls base spark timing
You can put a timing light on the engine, should see about 20-22 BTDC at idle