SkipshotMJ Posted June 30, 2010 Share Posted June 30, 2010 Hey guys, once again i have another problem with the comanche. The other day i put some new 5.0L Mustang Injectors in the comanche hoping to improve the performance. After i installed the injectors and put everything back together i started it up. It immediately started running rough as if i had just put a cam in. I ran it for a while like this thinking it would solve the problem but it didn't. The whole time the truck ran really rich and would stall at stop lights/ signs. Since it didn't solve itself i switched back to the stock injectors thinking that would work, but it once again didn't work. It runs a little better but the idle is still rough and it feels/ sounds like its running on 5 out of 6 cylinders. I check the connections on the injectors, the spark plugs, wires, cap, rotor, and distributor and there didn't seem to be any problem with any of them. I have a 1987 Comanche with the 4.0L I6. Any ideas? Link to comment Share on other sites More sharing options...
CWLONGSHOT Posted June 30, 2010 Share Posted June 30, 2010 Sorry I cannot tell you this or that is your problem... Just to be clear, the motor ran perfectly before the injector swap? Now, since the swap it does not? NOTHING else was done? Go back and retrace everything you did, take nothing for granted. Check all plugs to the TB. CW Link to comment Share on other sites More sharing options...
wannabeMJ Posted June 30, 2010 Share Posted June 30, 2010 not sure but it seems that the engine doesn't adjust to the new injectors so might wanna tchek the sensor for air/fuel mix Link to comment Share on other sites More sharing options...
SkipshotMJ Posted June 30, 2010 Author Share Posted June 30, 2010 Yea, the engine was running perfectly before the swap. After i put the 5.0L Injectors in it ran like crap. I swaped the old stock injectors back in (with new 0-rings) and it still runs like crap. Which sensor do i check for the air/fuel ratio and how do i check it? Link to comment Share on other sites More sharing options...
CWLONGSHOT Posted June 30, 2010 Share Posted June 30, 2010 I have the 4.6L FORD injectors and everything runs great. Noticed a improvement immediately in idle response and idle quality. No diff in performance and haven't been watching mileage. I'm still thinking you missed something. maybe some junk got into the injector bores. CW Link to comment Share on other sites More sharing options...
comanche09 Posted July 1, 2010 Share Posted July 1, 2010 Its possible that your ECU is bad. It may be continously firing an injector or two. Check the injector connectors with a noid light. If the light stays on and does not pulse, theres one of your problems. Good luck. Link to comment Share on other sites More sharing options...
1987Comanche Posted July 1, 2010 Share Posted July 1, 2010 I think you cooked the injector quad drivers in the ECU. I tried the same transplant in my '90 4.0 and it acted exactly as you described. I only drove it about 1 mile and swapped the OE injectors back in. At this point you probably need a new ECU to transplant with the injectors. Link to comment Share on other sites More sharing options...
SkipshotMJ Posted July 1, 2010 Author Share Posted July 1, 2010 Hey guys, thanks for the help, but it ended up being a misplaced vaccume line. The one that goes from the MAP sensor to the TB was in a wrong hole. As soon as i put it in the right hole it went back to idling smoothly. Thank god it wasn't something huge lol. Link to comment Share on other sites More sharing options...
1987Comanche Posted July 1, 2010 Share Posted July 1, 2010 Hmmmmm... makes me wonder why mine violently rejected the injector transplant. It did exactly what you described until I put the old injectors back in. :dunno: Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now