Off Roading Forums banner
1 - 3 of 3 Posts

Discussion Starter · #1 ·
I just bolted up a newly remanufactured Carter BBD and I'm wondering how you set the air to fuel mixture and how do you know when it's right? Same for the idle, fast idle, etc... It's an 89 Jeep Wrangler 4.2. It's been feeling as if it's missing just a little and I'm curious if that could be the air to fuel, or just the timing or something. Any suggestions? Thanks.


Discussion Starter · #2 ·
When does it feel like it is missing.... idle, acceleration? As far as air/fuel mix, the wonderful stepper motor does that for you! You can set idle mixture though and Im sure someone else will give you a proper technique for doing so.

85 CJ7, 350TBI ,T19 4spd
'00 TJ Sport, NV3550 5spd, D44, Teraflex system

· Registered
1,929 Posts
The Holley re-manufactured Carter I have says that all the settings should be close from the factory. If your engine is running rough, you should first check for vacuum leaks. If there aren't any leaks, adjust the idle screw until the engine idles at ~700 RPM. If the engine still runs rough or you are unable to get it to idle consistently, then you need to adjust the idle mixture. To adjust the idle mixture, there are two screws at the base of the front on the carb. These two screws need to be adjusted in or out. I recommend turning both screws all the way in and then backing them out an equal number of turns(6). Now with the engine running turn the screws in until the engine starts to get rough and then back them out one full turn. This should set the idle mixture.

I have spent a lot of time trying to get my Carter working correctly and am yet to succeed. The previous instructions are from Holley, but if you have $25 any good carb shop should be able to tune your carb and save you some headaches. I believe there are limitations to how well the Carter will work based on all of the emissions and computer controls.

Good Luck,

85 CJ7-4.2L,T-176,D300,2.5" lift,32"BFG MT,Durabak,York-Air,HEI?
1 - 3 of 3 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.