1988 propane conversion

[Copperhead]

1988 propane conv. No Spark

Help
1988 Ranger 4x4 2.3 propane conversion.
No start. Acting like bad crank pos sensor. Book shows sensor on 1989 and newer. Does this one maybe have a crank sensor or do I look elsewhere for the problem?
Thanks

edit: Coil fires once when commencing cranking then nothing.

I've pulled the cover but see no wires or sensor.

 

[Blackwidow1990]

check all grounds make sure they have good contact and are not broke

 

[cody93]

wait, it cranks and fires but wont hit? give er a shot of ether and see if it'll run for a sec. 88 had distributors IIRC. there timing is controlled buy timing belt, and position of rotor in respect to hall effect sensor.. line up the cam/crank marks on the pulleys and see if the No. 1 plug wire lines up with the rotor...

 

[Copperhead]

Thank you for the help so far.
To confirm then, it does have a distributor so there is no crank sensor, correct?
Also it DOES NOT FIRE.... Checking spark from the coil, it sparks ONCE at commence of cranking then nothing as long as you crank.
I'm using a spark plug wire directly off the coil and a remote starter button with the key on. One spark then nada.

 

[RonD]

'88 should have the TFI spark system, so yes, no Crank Position(CKP) sensor.

Good read here on TFI system and testing: http://www.therangerstation.com/tech_library/TFI_Diagnostic.shtml

A coil works by giving it 12volts and then cutting the voltage, the cutting of the voltage is what generates the spark, so the coil is given 12volts when key is on, but no Ground.
When there were points in the distributor the Ground for the coil was connected to the moving arm of the points, as distributor rotated the "bumps" on the shaft opened the points which cut the coil Ground and it sparked, then points would close and power up coil again.
On electronic ignitions with distributor they changed from points that always wore out to a sensor that didn't.
The sensor is connected to a module and the Coils Ground, sensor detects "bumps" and module cuts the ground to coil making it spark.
So same setup just less parts to wear out.

When you crank the engine power is being cut so coil sparks once, but it is not being repowered, that could be a sensor issue in the distributor or a TFI module issue, so test those.

There is often a separate Crank and Run voltage for the coil.
Coils don't last as long running at 14volts(alternator power when engine is running)
So there is a resistor used on the + voltage to the coil that will cut voltage down to 8volts while engine is running, but give coil 12volts when cranking.
To test if this dual voltage circuit might be the issue, run a jumper wire from battery + to the Coil +, then try to start.

I believe the TFI module has Start(crank) and Run connections

 

[Copperhead]

Thanks, changing the module now, distributor is out. Bearings reaaaaally bad in distributor.