injectors arent firing?
Thread Starter
Teching In
Joined: May 2010
Posts: 14
Likes: 0
From: Wilm, NC
injectors arent firing? I have a 95 LT1/M6. The car has been running fine, and then the other day the car cut off right after I cranked it, and would not start. I messed with a few things, and ended up leaving the car. Came back the next day, and brought some tools. Car cranked right up. Drove it home, ran perfect, didnt sputter one little bit. When I pulled into my driveway, the car cut off again, and now will not crank.
I have fuel pressure, and I have spark. I pulled the fuel rails and cranked it over, and sure enough the injectors arent firing at all. I can spray starting fluid, and it cranks right up.
My question is, what would cause the injectors not to fire? Is the ECU bad? The wiring, and all connections look perfect. I cant find anyone around here with an ECU to try, so I want to get some input before I buy a computer, and that not be the problem.
--Thanks for any help
--Joel
For the record, the car is an 86 RX7. Has a 95 OBDI lt1 out of a trans am
I have fuel pressure, and I have spark. I pulled the fuel rails and cranked it over, and sure enough the injectors arent firing at all. I can spray starting fluid, and it cranks right up.
My question is, what would cause the injectors not to fire? Is the ECU bad? The wiring, and all connections look perfect. I cant find anyone around here with an ECU to try, so I want to get some input before I buy a computer, and that not be the problem.
--Thanks for any help
--Joel
For the record, the car is an 86 RX7. Has a 95 OBDI lt1 out of a trans am
Registered User
Joined: Aug 2011
Posts: 17
Likes: 0
If you have a multimeter, check for power (12v) at one side of the injector plug. If that's fine, check to see if the other wire switches on and off to ground while cranking.
If there's no 12v+, then you have a power feed issue. You'll need to work backwards and find out where you're losing your power at.
If there's no activity on the ground side, culprits could be wiring/connectors, low res signal from the opti (i think, someone please correct me if i'm wrong, but pretty sure low res controls injectors in this case), or bad PCM, though in my experience most PCMs are pretty reliable unless subjected to extreme factors (shorts, liquids, bad ground/power, etc)
Not a definitive guide but may help point you in the right direction I hope.
If there's no 12v+, then you have a power feed issue. You'll need to work backwards and find out where you're losing your power at.
If there's no activity on the ground side, culprits could be wiring/connectors, low res signal from the opti (i think, someone please correct me if i'm wrong, but pretty sure low res controls injectors in this case), or bad PCM, though in my experience most PCMs are pretty reliable unless subjected to extreme factors (shorts, liquids, bad ground/power, etc)
Not a definitive guide but may help point you in the right direction I hope.
Thread Starter
Teching In
Joined: May 2010
Posts: 14
Likes: 0
From: Wilm, NC
If you have a multimeter, check for power (12v) at one side of the injector plug. If that's fine, check to see if the other wire switches on and off to ground while cranking.
If there's no 12v+, then you have a power feed issue. You'll need to work backwards and find out where you're losing your power at.
If there's no activity on the ground side, culprits could be wiring/connectors, low res signal from the opti (i think, someone please correct me if i'm wrong, but pretty sure low res controls injectors in this case), or bad PCM, though in my experience most PCMs are pretty reliable unless subjected to extreme factors (shorts, liquids, bad ground/power, etc)
Not a definitive guide but may help point you in the right direction I hope.
If there's no 12v+, then you have a power feed issue. You'll need to work backwards and find out where you're losing your power at.
If there's no activity on the ground side, culprits could be wiring/connectors, low res signal from the opti (i think, someone please correct me if i'm wrong, but pretty sure low res controls injectors in this case), or bad PCM, though in my experience most PCMs are pretty reliable unless subjected to extreme factors (shorts, liquids, bad ground/power, etc)
Not a definitive guide but may help point you in the right direction I hope.
Thread Starter
Teching In
Joined: May 2010
Posts: 14
Likes: 0
From: Wilm, NC
ok, so it seems there is no power going to the injectors. I traced the wires back to the ecu, and no power right at the ecu......Im guessing my ECU has crapped out. Now, I cant seem to find a ECU for my car anywhere for sale. Any suggestions?
#'s on the computer read : SERV NO.16188051
16209461
#'s on the computer read : SERV NO.16188051
16209461
