So I took off my fuel rail to clean the injectors today and I think I mixed up the wires that plug into the injectors. Started and ran just fine, anyway to tell and if I did what kinda damage will it do running it?

88 Cherokee L. 4.0L

 

???If it runs fine and they are now correct I don't get the problem???

 

If you mixed up the plugs it wouldn't be firing correctly and you'd know it.
You got it right bud

 

It does not matter about the order of the wires. At that stage in EFI development, everything was batch fire. This means that all (or half) of the injectors fire at the same time regardless of crank position. When the intake opens, the fuel air mix is sitting in the runner.

More recently, sequencial firing EFI systems are used. These fire each injector after the intake opens so the fuel mixes better with the inrushing air. This improves fuel economy and emmisions at idle and low RPM situations. As most know, this is not a trait our Jeeps posess. At high RPMs and high load, the injectors are on almost constantly flowing fuel during the power and exhaust cycles as well to get enough fuel into the runners.

 

[QUOTE=notop46;1344879]It does not matter about the order of the wires. At that stage in EFI development, everything was batch fire. This means that all (or half) of the injectors fire at the same time regardless of crank position. When the intake opens, the fuel air mix is sitting in the runner.

Absolutely untrue. The Renix Jeeps had sequential fuel injection. That's what the sync generator in the dizzy is for, to fire the injectors sequentially. When a sync generator fails the ECU batch fires as a default.

OP: If you want the wiring color codes for the different injectors, I can get them for you.

 

[quote=cruiser54;1344907]I would love them just to double check.

 

haha Thanks!

 

Crusier...If he had two injector plugs reversed wouldn't it run like doogie? Or along notop's line maybe it could run fair, as the pulse is still there, just a small fraction of a second off for those two?

I myself may have reversed 1&2 a few weeks ago changing my manifold gasket, not sure but it runs great so I let it go.......


....................................V.... ....V Thanks, I'll check and report back. (as well)

 

Not if his sync generator was bad and it was indeed batchfiring!!

OP, here are the colors of the injector hot wires. All the grounds are brown IIRC.
1-light blue
2-light green
3-tan
4-yellow
5-white
6-black

 

Thanks! Can't wait for 4pm to go do some more work on it

 

So 5 and 6 were mixed up. Now I'm leaking a little bit of fuel from the rail at this connected. If I push it together just a little it stops. Any fixes?

 

There's a repair kit from Jeep or Napa to re-seal the connection. Important, as a leak there on to the exhaust manifold equals FIRE.

 

Yeah that's why it's parked until I fix it

 

Chrysler part number 83502745.

 

Autozone sells a cheap set of HelpME injector O-Rings,it has rings for multiple types of engines, the ones for the injectors are trash, but the thin tan ones that fit the fuel line, and the return line are okay.
If you need it tonight or before you can get to a dealer to get good ones.