Hi everyone! New to the forum and I have a question. I bought a YJ and am having problems with it stuttering. It won't go more than 60mph. I have tried to set the timing but I do not understand the sticker that is on the jeep. When I am going through the gears it bogs down and I have to shift earlier than I normally would. Any help would be appreciated.
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Could you fill out your jeep profile on the forum? Do you have a 4 cylinder or a 6 cylinder? this can make a big difference.
You need to start by doing a general tune-up of things that need to be updated anyway:
1.) New standard Champion copper core spark plugs. Do not use platinum or Irridium.
2.) Spark plug wires (choose your favorite flavor of price vs quality)
3.) New distributor cap and rotor
4.) New Fuel Filter
5.) New or Cleaned Air Filter
6.) since you are bogging under load, it is unlikely that you have a vacuum leak. you should still check though by spraying carb cleaner on all of the vacuum lines in the engine bay while the vehicle idles. Listen for a change in RPM.
Poor maintenance in the above can easily cause the symptoms you've been describing. After updating (or confirming that they are up to date) come back and we can walk you through the more advanced diagnostics.
It is electronic ignition no wear parts so timing never goes "off" unless it was messed with.
If it has the factory emissions hooked up, it sets like the sticker says, vacuum line unplugged and blocked, the vacuum solenoids unplugged and at 1600 rpm, usually at 9° BTDC.
Bogging out can mean gas filter or messed up gas tank venting. Filter is only good for a year or so, so I start there. Be sure it sits level with the smaller return line up top. To check the venting, just drive with the gas cap cracked loose.
The carb is plugged in at the back right? That big plug is a stepper motor that controls the mix. If the pins are not moving, you can see the top pin from the top, that can affect high speed also. The pin should be centered when it is warmed up at idle with about 1/8" of shaft showing from the back wall before the taper.
86/00 CJ7 Laredo, 33x9.5 BFG AT's, 'glass nose to tail in '00, 'New' frame,wires and plumbing in '09. Carter BBD Carbed 4.0 HO in '10.
89 YJ Renegade. BBD Carbed 4.0 HO. Locked front and rear with 33x9.5 BFG AT's
Some Canadian Bush Jeep Runs and Build Photos: http://mikeromainjeeptrips.shutterfly.com (10 new albums added Sept 16/10)