I am trying to figure out this issue. The engine will start and run although sometimes it’s hard to start and sounds like it has no compression. Compression test is good, timing is good, head rebuilt, new plugs wires and injectors. New exhaust. It’s been at a mechanic shop for almost a year and he is stumped. Fuel pump new. Any help would be appreciated.

 

Welcome to the forum

Ranger used 2 different 2.3l engines
1983 to 1997 2.3l Lima

2001-2011 2.3l Duratec

Which year do you have and manual or automatic trans?

 

It’s a 1997 with the 8 plugs and an automatic.

 

How old is the timing belt and tensioner?

How old is the upstream O2 sensor?

Does it always run fine when cold?

If its an odd intermittent issue then very hard to track down, but could be the computer
I would unplug the MAF sensor and see how long it takes to set MAF code, should be instant, CEL(check engine light) comes on
Same for Air Temp sensor
Also CAM sensor
One at a time of course and after engine has warmed up
These are just three sensors that are use but not needed to run

I assume CEL has not come on during poor running conditions?

 

The timing belt and tensioner are new. I can’t remember if the O2 sensor is new but I think it is. It takes a bit to get it started when it’s cold but it seems to run smooth once it does start but as soon as you touch the throttle it dies. Once it’s been running for a bit you can ease into the gas but it will die before you ever reach full throttle. And you can forget about snapping the throttle!

 

On the engine is the FPR(fuel pressure regulator) it has the Return fuel line attached and a Vacuum hose, check the vacuum hose for gasoline, should NOT be any

Do you have a way to test fuel pressure?
Should be 30-40psi running, 20psi key off

Unplug the TPS(throttle position sensor), its a 3 wire plug, see if you can open throttle without engine dieing
Also make sure CEL comes on

The CEL is the big deal if its nopt coming on there IS a computer issue

You can chases your tail for days if there is a computer issue, its unlikely, but can happen

 

Thank you very much for the suggestions Ron. I will check it out and let you know what I find.