Ok Now What?

[NoKaOiSURF]

ok so i changed the ecm, icm, and distributer......still no spark

 

and the tach still jumps all over...what could that be?

 

the wife is getting mad at the $$$$ being spent

 

if can help let me know

 

 

aloha and mahalos

[GhostPath]

ok so i changed the ecm, icm, and distributer......still no spark

 

and the tach still jumps all over...what could that be?

 

the wife is getting mad at the $$$$ being spent

 

if can help let me know

aloha and mahalos

 

Check the coil and then check for blown fusible links.

[NoKaOiSURF]

how do check the coil?

 

 

i hooked a meter to check resistince on the links and they looked clear

[GhostPath]

how do check the coil?

i hooked a meter to check resistince on the links and they looked clear

 

 

The easiest way is with a coil tester.

 

That said, the tach can only jump around if the coil is firing. What condition are your plug wires in, and do you have them (and the coil wire) hooked up properly.

[88pathoffroad]

There's a "power transistor" on the coil (essentially a high-speed electronic switch) that the ECU usess to fire the coil. The ECU's circuitry can only handle so much juice, so they used the power transistor to recieve low-voltage (or low-amperage) signals and thereby trigger the coil. You can test that if you're comfy with a voltmeter set to the resistance/ohm setting. I've got to get Acrobat running on my puter again so I can post the info on how to test it, it should be in the EF/EC section of the 94 Pathy FSM if you have a copy. You can get a free copy at phatG20.net if you don't already have one. The info for the power transistor should be good from 90-95, I don't remember what year yours is.

[GhostPath]

There's a "power transistor" on the coil (essentially a high-speed electronic switch) that the ECU usess to fire the coil. The ECU's circuitry can only handle so much juice, so they used the power transistor to recieve low-voltage (or low-amperage) signals and thereby trigger the coil. You can test that if you're comfy with a voltmeter set to the resistance/ohm setting. I've got to get Acrobat running on my puter again so I can post the info on how to test it, it should be in the EF/EC section of the 94 Pathy FSM if you have a copy. You can get a free copy at phatG20.net if you don't already have one. The info for the power transistor should be good from 90-95, I don't remember what year yours is.

 

 

I'd forgotten about that - yeah, that transistor is probably fried, too. The ECU is trying to fire the coil, but the transistor isn't tripping the coil - and it's doing weird things too.