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View Full Version : Cranks, no spark, random electric surges in ON position....



PharmorJawn
05-09-2018, 04:12 PM
1994 MM sport 2.4

As the title says....
When i crank over the motor i get no spark but when i stop cranking and leave the key in the on position, i get random clicks(relays most likely) and my tach needle goes crazy.
I have replaced/checked almost everything. Ive been searching my Haynes and the site but cannot seem to get anywhere.

Replaced:
All relays/Fuses
Plugs
Wires
Cap and Rotor
Ignition Coil
Ignition Switch

Checked(with multimeter, all within tolerances):
Pretty much every sensor including the ECM(also no phsyical defects noticed)

Am i missing something? Please HALP! Im loosing my mind(and money lol)
Thanks in advance!

bitrootvz
05-10-2018, 09:02 AM
It's probably 1 of 3 things, bad ground-MFI relay or Computer. Pull the plastic kick panel on passenger side under dash. while you have one hand on the key grab the wiring harness at the computer and relay. turn on the key and wiggle the wires. observe. Next try starting it while wiggling and see if it starts. last try hooking a wire with alligator clips on a good ground and the computer and try. If this doesn't work then you'll have to do the whole trace wires and test parts. I now have a box of parts that are probably good so keep in touch. I also have a computer out of a 93 but don't know if it's good as the 90 I have won't work with a 93. Don't buy a computer from the guy in Colorado mine crapped the bed in less than 100 miles.

tortron
05-10-2018, 01:37 PM
Wouldnt be surprised if theres corrosion in the fuse box

PharmorJawn
05-10-2018, 04:11 PM
Mfi relay was replaced with new already. Ill check my grounds and see where it gets me. Also noticed oil in my distributor last night, pulled it apart and the photo optic sensor was covered in oil. Going to pick up the new right now. Fingers crossed ;)

PharmorJawn
05-10-2018, 06:02 PM
Put the new distributor in and it fired right up. I little rough but nothing i cant adjust out. Thanks for the help anyways :thumbup:

bitrootvz
05-11-2018, 11:11 AM
any idea how the oil got in there? "O" ring or worn shaft.

geezer101
05-11-2018, 04:59 PM
The O ring only seals the body from leaking externally so it's either just been fouled from a rocker cover seal or something inside the distributor has excessive wear (not unlikely when you think about what it does and what drives it)