I just got a 91 Ranger with the 2.3l engine. I was able to drive it about 40 miles home but the seller had it running when I got there so I didn't hear it cold start. It would not start the next day. I have checked everything that I can think of and could find here and on youtube and I am stumped. Hoping one of you can point me in the right direction.

Facts:
Cranks but will not start
It has gas in the tank.
Will fire with starter fluid but will not stay running.
I can hear the fuel pump running.
I tested the fuel pressure and get 40lb when the key is turned on
the inertia switch is not tripped
I changed and properly gapped all of the spark plugs and wire
I used a noid tester on the fuel injection and it blinks appropriately
only threw 2 or 3 tools across the yard.

 

Welcome to the forum

Good testing

If it starts by adding fuel manually(50/50 test) then spark is timed and working, and you have enough compression
So its down to fuel delivery, well lack of fuel delivery, lol

All cold gasoline engines need to be CHOKE
With Fuel Injection the Computer has to operate the CHOKE
CHOKE means RICH fuel mix with high idle

An ECT(engine coolant temp) sensor was added to fuel injection engines so computer would know when, and how much Choke to apply to engine for cold start
The dash board temp SENDER on a 1991 2.3l will be on the drivers side toward the rear near the oil pressure switch
The ECT sensor should be on the front of engine near thermostat housing, its a 2 wire 5volt sensor, should have a grey/red wire and a green/red wire

Its possible that sensor is showing warm engine all the time, so no choke mode

You can leave the air tube off the intake, MAF sensor isn't needed for start up and idle, and keep spraying fuel in to keep it running until it gets warm enough to not need a Choke


Other issue is water in the tank/fuel

You could change fuel filter, should be done when you get any "new" vehicle
While filter is off put a clear glass jar under the fuel line and cycle key on and off a few times, to collect the fuel
Let it sit for a few minutes, you can easily see water settle to the bottom of jar
Water and gasoline can't mix
When driving fuel sloshes around, when vehicle sits over night the water settles to the bottom, and that's what the fuel pump sucks in FIRST

You can also crank engine over a few times, don't add fuel
Pull out any spark plug, its tip should be WET with fuel, try to light that fuel, it should BURN if its all gasoline, if it don't burn it ain't "fuel", lol

 

Thank you for your help. I am unfortunately still stumped. I changed the fuel filter and tested the fuel in the ways you mentioned. I captured some of the fuel out of the old filter and out of the tank like you said and there was no water in it. But when I pulled a plug I could smell the fuel but it would not light. I found one of the sensor/senders you mentioned but I can't find the other. One of them ( I believe is the ECT sender ) is under the intake manifold right above the oil filter. The ECT sensor is no where to be found. I looked all around the thermostat housing but nothing is there.

 

ECT Sensor is in a odd location
Its under the center of the intake manifold just forward of where the SENDER is located, sender is at the rear side by oil pressure sender: https://ww2-secure.justanswer.com/up..._134430_A1.jpg

Google: 90 ford ranger 2.3l temp sending unit sensor location's and what they look like

2min video, not great but gives you an idea of where to look

 

Ok here is a video. Go to 5:49. He refers to them as the same thing. If I intend to test these how would I go about it or is the way to test them to replace them? Also is it the same thing for both ports? I am not sure what to buy.

 

ECT sensor will have 2 wires, always, and its a 5volt sensor, powered by computer

ECT sender will usually only have 1 wire, uses engine as the ground, so don't tape the threads, and it uses 12volts

So not interchangeable

ECT sensor will have a light green/red stripe wire and a grey/red stripe wire attached

There is also a Air temp(IAT) sensor on the intake, looks similar but uses Grey wire and grey/red wire

In the video the unit he points to with the GREY connector(on intake) is the ECT sensor, for computer
The one farther back that's painted over is the ECT sender, for dash board temp gauge

 

Ok so strange thing happened. I pushed it in the garage this morning because it was going to start raining and I wanted to be able to work on it tonight. The plan was to change out the sensor/sender. So it sat in the garage until I got off work about 2 hours ago. I got in and turned the key trying to get lucky and it started right up. I have no idea what changed. Yesterday I changed the air filter, fuel pump, and put back on the throttle cover and hose between the MAF and intake. That is all I did but it didn't start yesterday. So I am not sure if it is a fluke or what but I drove it around for about an hour. I can confirm the tac and temp gauge do not work but everything else appears to. The parking brake also is seized up and the brake light on the dash was on for about 30 minutes before it just turned off. Not sure if any of this info is important but thought I would share it anyway. You have been a huge help Ron!

 

If its helpful, the only "sensor" that can cause a No Start is the crank sensor, not cam sensor, crank sensor, its behind the timing belt cover above crank shaft
And these rarely fail and never fail intermittently, when they die they die

The ECT sensor sets the Choke, it can cause a hard cold start, but not a No Start, should still fire but run poorly
MAF sensor, O2 sensor, IAT sensor, are not used for start up, but can cause poor running after startup

Doesn't matter what "they" add to the outside of a gasoline engine, what makes them run never changes, the big 3
Compression, above 120psi
Fuel, mixed with air
Spark, at the right time

Only sensor involved in the big 3 is the crank sensor, it times the spark, like a distributor did, but way way simpler and better

This is why you should do the 50/50 test when there is a no start
Spray fuel into the engine
Try to start
If it starts then spark is OK
If it doesn't start then no spark

If an engine doesn't start then it not a sensor issue
If an engine starts but runs poorly then it can be a sensor issue

 

So this morning it started right up but ran really rough and died a couple times. After keeping it running for about 3 minutes it smoothed out and ran great. Would you think that this could be the ECT sender?

 

Yes, that's what it reads like

ECT sensor runs the Choke, all gasoline engines need to be choked until they warm up

 

I changed it and it started and idle correctly right off the bat. Gonna try a few more cold starts over the next couple days to be sure but I think we got it. Thanks so much for your help!

 

Good work

Thanks for the update

 

Well back to not starting. Ran good for a couple days though. Today I ran a 15 minute errand and it ran fine. Later I went to run another errand and it started but died after about 30 seconds of idle and I couldn't get it started again.

 

Feels like the same issue.

 

Might be time to pull the computer and have a look inside

 

What am i looking for?

 

Looking pretty good in there

Move the blue cylinder capacitors with your finger to make sure both wires on each is still attached

These will give you problems in the future so you can replace them now, under $5, if you can solder

And what about the 60-wire connector and pins, no obvious corrosion on those?

Pin 7 is for the ECT sensor, numbering seen here: Ford EEC-IV

 

some slight discoloration on them. should I get a new computer and if it doesn't work take it back?

 

ok found a computer at oreilly so I went and got it. installed it and it started right away. It was idling very high but at least it started.