90 1g with 91 ignition system

[MellowVR4]

see if i can get some help here, i have a 90 dsm with a 91 ignition system and ecu. still has the 90 cluster but the tach doesnt work, i reed the way to fix it but thats not the problem. the car is misfiring a little, would the the tach not working cause the car to misfire?? because the ecu isnt getting the signal?? or could it be a normal reason why its misfires like fuel or spark related. please any help will be appreciated.

 

[Lofty]

I'm assuming it has the 90 harness?

 

[MellowVR4]

yes , but the changes have bin made for 1g ignition system. number 4 white wire on the transistor goes all the way to the 109 pin on the ecu.

 

[MellowVR4]

what will make the third cylinder injector not to spray??? thought it was the injector but replaced it, and same issue. its getting voltage but still nothing. anyone have any ideas.

 

[grocery_getter]

Does it have 12v with the key on ON? If it does then it just didn't get a ground signal. Maybe from ecu, maybe from bad wiring.

 

[MellowVR4]

yes it does read that