Engine won't stay running

[JoshErnst1074]

So I have an '89 2.3L ranger which I swapped a '90 2.3 into. This engine runs with the alternator unplugged, or if I increase the load. Like turning headlights on or blower motor. Otherwise it sputters and stalls. I've checked the ignition control module ground and power all that works. CPS is getting a good ground also. I have a few codes I got while running the engine. 21: Engine coolant temp (ECT) out of self-test range. 33: EGR valve opening not detected. 13: Cannot control rpm during self-test low rpm check. 77: Operator error (Dynamic Response/Cylinder balance test). 52: PSPS circuit did not change states. Since I did the motor swap the power steering hasn't worked. Which makes sense that it would throw that code at me. I cannot figure this out. This is the weirdest problem I've ever had. I know I've posted a few threads on this but I keep getting new info. Thanks guys, I really appreciate everyone's input.

 

[RonD]

I assume engine does NOT run with alternator connected?

Bad voltage regulator can cause alternator to output 15+ volts, or even AC power, very bad.

Running off battery power will cause all sorts of issues because it is simply is too low a voltage at 12v to operate system very long.
System is setup to run with 13.5v, normal alternator output

 

[JoshErnst1074]

Engine runs PERFECT with alternator UNPLUGGED, and MISSES with it PLUGGED IN, but still runs until it stalls out. Replaced voltage regulator, then replaced whole alternator. Same problem

 

[RonD]

Then issue would be in the wiring for alternator.

An alternator is turned on and off by the key switch via the voltage gauge and/or "Battery" light on the dash.
Do these work?
Voltage gauge needs to work for alternator to work
Battery Light needs to come on with key for alternator to work, if you have a Battery Light, they are not standard

The voltage regulator works by supplying the alternator rotor with 5 to 9voltsDC via the brushes, the spinning of the rotor with voltage applied creates AC voltage in the 3 Fields in the outer case of the alternator, each field has 2 diodes that converts the AC to DC voltage which is then sent out the B+ connection to vehicles power distribution system.

The voltage regulator monitors "system voltage" and increases or decreases the 5 to 9volts going to the rotor to increase or decrease the voltage output from the B+ connection.
Target voltage is 13.6volts.

You should have an alternator with internal regulator on an '89
There will be the large B+ connection on the back which has two wires connected,
Black/orange < to 50amp fuse in power box, fuse 7
Orange/blue < to 60amp fuse in power box, fuse 3

Then a 3 wire connector,
yellow/white wire < connected to the B+ black/orange wire usually at power distribution box
white/black wire < this is a short jumper wire that needs to be hooked up to a single connection on alternator
green/red wire < this is the wire from the key switch via the voltage meter


Any of these wires can get frayed over the years of removal and reinstalltion.

 

[JoshErnst1074]

The voltmeter in the dash works, and the battery light works also. When the engine is running the battery reads 14.5 volts.

 

[JoshErnst1074]

Now the ignition switch is all messed up. It starts without a key, and sometimes the starter never disengages until I pull the negative off the battery.

 

[Mark_88]

My 88 2.0 did that for a bit and it wasn't actually the starter switch, but the solenoid under the hood. They can short out and cause the starter to stay engaged. I'd have a close look at yours for cracks in the solenoid case or see if the posts are somehow arching out...

At first I thought mine was the switch also...but swapped out the solenoid and it cleared that right up...and that could also be giving you some of your symptoms...

 

[JoshErnst1074]

I already put a brand new starter relay in though.

 

[Mark_88]

Was that before the starter kept engaging or after?

I've put in new ones with the exact same issue right out of the box. Took me a while to figure it out but fortunately I had an old spare and tried that one before tearing anything else apart...like the steering column...and it put a stop to it right away.

Some of them have no divider between the posts...others don't and those were the ones I was having problems with...

If not that...then could be the ignition module...mine had the same wonky symptoms (still does, actually).

 

[JoshErnst1074]

I checked the icm for voltage and ground and they both checked out good. Are there other things in there that could cause it? And I replaced the started relay with a brand new one.

 

[RonD]

The starter relay has two larger posts and one smaller post and your trouble might be there.

Just go over the wiring one more time.
Starter motor wire goes to one of the larger posts, and that's the ONLY wire on that post, double check this, it is the ONLY wire on that post.

The other larger post will connect to battery + wire
It will have other wires connected with it, sometimes alternator wires, and power box wires.

Small post wire comes from ignition switch, it should only have 12volts on it when Key is turned all the way to START.
If you have an older 4 post starter relay then this wire needs to be on the "S" labeled small post, "I" post will not be hooked up to anything.

The ignition switch is under the steering column, the key switch pushes and pulls a metal bar that slides the ignition switch into it's various positions to make or break contacts.
Yours could be going bad.

 

[JoshErnst1074]

It was the icm! I went out and bought another one and it runs perfect!

 

[Mark_88]

Cool...and does the starter keep cranking?

I guess it must have been fried and was causing a voltage surge or something...

 

[JoshErnst1074]

I'm redoing the whole ignition switch this Friday. Ordered a lock cylinder with a key, seeing as though the guy I bought the truck from swore he was gonna mail me a key and never did.... Quality people. Anyways the icm however is making a very rapid clicking noise. Like you can hear the arcing of the spark. But I don't see any arcing. Is that normal operation for an icm? Do they tend to make noise normally?

 

[Mark_88]

My 96 has an icm (I'm pretty sure) but I never heard it clicking and I spent quite a bit of time listening to the engine before I bought the truck (it's a donor for my current truck) so...unless it was muffled by the fan noise or something else...I'd say it's not supposed to click...at least not loud enough to hear it.

Was this observed by normal methods or did you put a stethoscope on it

I've lost track, but did you at any time replace the computer (ECM or whatever)?