#1 and #2 injectors are not firing

[Cnock]

i recently put in my new 650's and now my first two fuel injectors arent firing. when i use my logger to shut them down it makes no difference but when i shut down my 3rd or 4th my engine stalls. at first i thought it was my fuel injectirs so i switched the ones i knew worked and the other ones but i still had the same problem. what could cause this?

 

[GTM]

Originally posted by Cnock
i recently put in my new 650's and now my first two fuel injectors arent firing. when i use my logger to shut them down it makes no difference but when i shut down my 3rd or 4th my engine stalls. at first i thought it was my fuel injectirs so i switched the ones i knew worked and the other ones but i still had the same problem. what could cause this?

Are you getting fuel at any time out of 1&2?
Have you checked continuity with a multi-meter? Have you done a compression check? Do you have a known good spare ECU?

Cheers,
GTM

 

[SoMeKiD]

You have an older car (if it is 92 listed under your profile). The harnesses on these cars are getting brittle and can crack easily. Look at the wiring from where it connects on to the harness back. My #1 and #4 injectors were BARLEY getting any kind of pulse becuase their wiring was cracked and hanging on by 1 strand of wire. I cut, cleaned and resoldered the wires, and the injectors began firing normally again.

 

[mike97gsx]

Are you sure your injectors aren't firing? Are you sure you're just not getting a spark?

When you have the car running, hold the injector clips between your fingers and feel for a pulse. If you feel it pulsating, they're firing. If they are firing, check your plugs, wires, coil pack, etc... The usual spark related stuff. Do a search, there are tons of threads on no spark problems.

If you really don't have an injector pulse, do what the other guys suggested.

Good luck,

Mike

 

[Cnock]

Originally posted by SoMeKiD
You have an older car (if it is 92 listed under your profile). The harnesses on these cars are getting brittle and can crack easily. Look at the wiring from where it connects on to the harness back. My #1 and #4 injectors were BARLEY getting any kind of pulse becuase their wiring was cracked and hanging on by 1 strand of wire. I cut, cleaned and resoldered the wires, and the injectors began firing normally again.

what harness are you referrring to? the one that clips to the injectors?

 

[GTM]

Originally posted by Cnock
what harness are you referrring to? the one that clips to the injectors?

Yup, that's the one. With the injectors plugged in you can remove the ECU end and pin it out to see if you have a complete circuit to and through the injectors. Or you can check each wire seperately if you connect a long jumper wire from the injector wire back to the ECU plug. Of course a data logger or a newer Palm Pilot would tell you all of this if you have access to one.

Cheers,
GTM

 

[sicawd]

if you have acess to a pocketlogger, you can tell if your injectors are not running right when the "injector circuit" cel is triggered.

a easy way to check if you have spark, unplug your spark plug wire from the spark plug and stick another spare into it and start the car to see if any spark is present.

goodluck
later.