Completed Project Kirby's 1991 Ranger Build Up

[Kirby N.]

The thing just keeps starting worse! I finally found an ecu that I think will work. Apparently exploders had no cam sync until like mid 93 and rangers didn’t have one in 93 or 94, but the ecus are different on some 94s and are not mounted in the kick panel. The connector on the 93 that was in the kick panel was different.

But it found a non cam sync 1993 exploder sport manual at the junk yard- so I am going to give it a shot. It was auto case but I don’t think that will matter.

So here goes nothing! If this isn’t it- idk what to try.

 

[Kirby N.]

The 4 digit code is ANY1

I guess that means it will work for anyone.

 

[Kirby N.]

The ecu worked with my truck, but the truck behaves the same. It seems like a fuel issue to me. Maybe I’ll put in my spare fuel pump tomorrow and see if it fixes it.

Any ideas?

 

[1sicbronconut]

Did you try starting it with the MAF unplugged? I've seen issues over the years caused by bug parts stuck in the MAF sensor.

 

[Kirby N.]

No but I will give that a shot

 

[Kirby N.]

I think I’ll put in another new fuel filter, change oil and try it. I’ll probably also swap to my spare fuel pump just to rule that out.

What is a head scratcher is that it idles like crap. With the used iac it will get down to 750rpms for idle but it will barely stay running and I turn the wheel and put any load on the engine and it dies. And it has had the idle issue since the engine swap.

So there is more than just the hard start symptom, though it is the most glaring issue right now.

no codes to speak of. I really don’t think the pump and filter are going to make any difference- but I am out of ideas

 

[410Fortune]

Compression test? I mean could it have a miss / stumble that is just hard to catch?

 

[Kirby N.]

Hmm. That’s a thought. I also wonder if it has a plugged up injector or something.

 

[Kirby N.]

I wish we would have kept the old injectors.

 

[410Fortune]

Can listen to them
Click when running a stuck one usually won’t click

Spark plug would be oily if not firing or wet with fuel if injector stuck

Smell oil does it smell of fuel? (Injector stuck open)
Otherwise I know 4.0
Ohv heads are hit and miss on rebuild I’ve seen some strange things… like valve stem seals came right off after hundred miles (8 out of 12). Not only did the head builder paint the sealing area with cast blast but they also used cheapo seals… that sucker was drinking two quarts of oil a week

 

[Kirby N.]

Hmm. I will check the oil smell. I am going to do an oil change today. I also got a compression tester so I may try that test.

I also started thinking about the crankshaft sensor on the front of the engine- but I would think that would trip a cel

I got some ideas. I’ll get to work after lunch.

 

[Kirby N.]

I’ll also do the stethoscope on the injectors and make sure they are firing.

 

[donalds]

I had a crank sensor go bad no check engine light
it was intermittent on cold days after it rained
It would not start and Run poorly
I had to use a scanner and watch the rpm pid in forscan to figure it out
Also the grooves on the harmonic balancer If they're rusty you get a bad signal

If you unplug it and plug it back in a few times It worked for a little while

 

[Kirby N.]

Ok, 93 computer in and I drove it 30 minutes twice- both times it gives me a solid check engine light. My code reader isn’t working for koer test. Idk what the deal is. I am going to try new batteries, maybe a new reader. With the koeo test, It threw a 176 code-lean on drivers bank- but my Ranger only has one o2 sensor pre cat. Idk if a 93 has the same amount of o2 sensors or not. It’s odd the 93 computer throws the light and the 91 doesn’t.

I put in a brand new Carter fuel pump (I forgot that I warranty’d it.) Made no difference. So I put the motor craft one back in.

Changed the fuel filter, no difference.

Tried my spare maf sensor and reset the computer. Made no difference.

While cranking I wiggled the crankshaft position sensor- made no difference. I unplugged the crankshaft sensor and it would not start without it and when running if I unplugged it, it would die. So I think it seems to be doing its job.

All the injectors are clicking the same way when running.

When starting, usually it sounds like it is going to fire right away then doesn’t and goes into this long cranking thing. If I time the throttle right, sometimes I can get it to start relatively soon, but if not it just cranks forever.

I got a compression tester but I ran out of time to use it.

I have the old coil pack- I suppose I could try that or a junk yard one.

Thanks for the ideas @donalds and @410Fortune and @1sicbronconut

 

[Turdle]

Idea.

Check the throttle position sensor with a multimeter. See if there are any spikes in voltage through it's travel from idle to wot. Also, make sure it's below 1 v at idle, like .96 v or so.
Should go smooth from .96 to almost 4.9 v


My 93 with any1 ecm had 2 O2 sensors, no cam sensor wired in, no egr. Auto trans., Sequential injectors ( different color wires in every injector)

Also. On mine, I did find some green goop growing on the bus connection to the power side of injectir's12v line, in the harness itself.

 

[Kirby N.]

Thanks I’ll give that a shot. I also have a spare tps- I was considering trying that too.

 

[410Fortune]

93/94 had two 02 sensors

Good work this far! Eliminating things as the culprit! Next time it does the long crank thing check for spark

 

[Turdle]

Ohhh. Ignition module. Almost forgot about that pesky thing. Good call @410Fortune



If you do check the ignition module later, just want to throw this in now. It's hard to unplug it without breaking it. Beware

 

[Kirby N.]

Thanks! I did “Check” the ignition module by putting in another one that I got from a buddy and he thought it was good. It did t change anything.

I’ll do the spark check. My dad has a cute little tool for that.

 

[410Fortune]

Also check the wiring and connections at the timing pil, make sure all is clean and tight

All grounds are suspect, the ignition and pcm grounds as well as every ground you can see.. must be clean and tight. Battery should have 3 good grounds, one to drivetrain, one to body and one to frame. Some years of 4.0 also have big ground direct to starter bolt… this would be the drivetrain ground

Will be interesting to know if lack of spark is causing the long crank