Ignition timing etc. 1994 2.3L 5 speed

[jcastilow]

Hi,

I've been cruising the forums and reading some articles and have a rough idea about ignition timing, crank position sensor etc. but I'm hoping someone more knowledgeable can help me out. I'll try to lay this out clearly.

I bought a OBD1 code reader. It pretty much told me every sensor was bad and after some reading and testing I determined the PCM itself was the problem. Went to NAPA bought a new PCM and viola! everything works. KOEO tests says no faults - yay!

Next test: Key On Engine Running. The manual for the code reader says, though, to be sure the ignition timing is set correctly or the KEOR test will give false readings. Ok... I go and look at the factory service manual and it just references another manual (emissions controls) for distributor ignition system.

Now the questions:

My 1994 2.3L Ranger Splash (with federal emissions) has an electronically controlled ignition system, the DIS - right? It's not adjustable, but it could fail. If it did fail - the truck would probably not even start. Is all that correct?

Does my 2.3L have a crankshaft position sensor and/or a camshaft position sensor? Would these affect the timing, and if they failed would the truck run? If it would run what symptoms would tip me off they were not working?

Lastly, is it basically safe to assume the ignition timing on my Ranger is good?

Thanks for any help. Little by little it's getting there.

 

[RonD]

Welcome to TRS

1994 was the last year Rangers used EEC-IV computer, 60-pin, with OBD1 communications

It does have distributorless spark system, run by a Crank sensor and ICM(ignition control module)
Module is on the front of the lower intake
ICM controls the 2 Coil Packs

Crank sensor, ICM and Coil packs are an autonomous system, BUT........
ICM does send Computer the Crank sensor pulse(RPM, PIP) and computer sends back "suggested" spark advance/retard instructions(SPOUT) to ICM, the computer has "driver" input, like gas pedal position(TPS), so can help spark to be more responsive to drivers input

Cam sensor's were mainly used for Sequential Fuel Injection, they also help for better emissions, Calif Rangers had them, yours may or may not have it.
Cam moves at 1/2 the speed of the crank, so has better "resolution" of engine dynamics.

In 1995 Rangers got the EEC-V 104-pin computer with OBD2
All Rangers then used Cam sensors and Sequential fuel injection
And ICM was built into computer
2.3l also got a different Crank sensor, VR style, 1994 and earlier used Hall Effect, this is important because you can not swap a 1995-2001 2.3l/2.5l into a 1994 or earlier Ranger, and visa versa, because crank sensor placement and type were changed

Yes, there are no user adjustments for spark timing on distributorless systems.
Yes, the ICM did have there issues on the 2.3ls, most auto parts stores can test them
Could be No Start, but rough running could also be a sign of failing ICM


One heads up
Only the Exhaust side spark plugs(coil pack) are working when starter motor is turning engine over, this gives all available voltage to those 4 spark plugs
Intake side spark starts above 400 RPM, engine started

 

[Ragingbull]

My CEL came on and the code was 224, it still ran fine and the mileage was about the same as usual. I had put an explorer cluster in with a tach and it showed half the rpm. Finally purchased a new ICM and all worked like new for another 80,000 miles. I will say that when i changed the ICM, i also had to change out the coil packs. 2 and 4 on both packs were burned inside the cups from running it with a bad module. Also if it is replaced make sure you use Heat Sink compound and not dielectric grease when installing the module. Part # SL203 at Autozone.