Can somebody please help me I built a buggy and I have a 98 4.0 with a 5-speed behind it out of a Wrangler I have the complete engine wiring harness and computer but I can't seem to find anyone that has built a standalone harness for the 98 Wrangler I have been working on this harness problem for 5 months if anybody could help me it would be greatly appreciated I just need to know what wires I need to have power to from the computer and what wires have to be grounded are no wires inside the cab I am using old school gauges so I just want a starter switch and that's it I just need to get this motor running please help
Stand alone wiring harness
- Thread starter Robbinsauto
- Start date
The FSM with wiring diagrams - section 8w...is in the resources section.
Are you using a programmer to remove things like evap?
-Mac
Are you using a programmer to remove things like evap?
-Mac
Eventually I will be but I just need to get the motor to run right now so I can move in in and out of my shop and it sucks pushing it in and out every day
Id install the harness as is and get it running. Then thin out a wire or two, check things, rinse, repeat.
Otherwise you'll be chasing your tail.
-Mac
Otherwise you'll be chasing your tail.
-Mac
But all I have is the engine harness and computer the Jeep is no longer there's no longer exist it's all a tube buggy so I'm trying to just figure out what wires I have to run power to and ground to to get fuel spark and crank sensor
How much is left of the wiring harness?
The PDC and engine harness should plug into the PCM. Battery cables to the starter and PDC. Everything plugs into the color coded wiring block.
Do you have an ignition module or are you just doing a switch?
-Mac
The PDC and engine harness should plug into the PCM. Battery cables to the starter and PDC. Everything plugs into the color coded wiring block.
Do you have an ignition module or are you just doing a switch?
-Mac
Conversationly - wouldn’t be easier/ maybe more cost effective long run to not go through all that and modify the factory ECM and just use a mega squirt? Doesn’t need gauges just a way to run the injectors… not the most experienced here so just a thought.
Although I think OP maybe just looking for easiest route to get it under power for the moment.
The factory service manual for the 98, section 8W in particular, is going to be invaluable to you. It's in the Resources section here.
But maybe I don't understand what you mean by building a standalone harness. There's quite a bit that goes into making the 4.0 fire up.
But maybe I don't understand what you mean by building a standalone harness. There's quite a bit that goes into making the 4.0 fire up.
Just to save the inevitable next set of questions:
https://wranglertjforum.com/threads...ice-manuals-fsm-technical-documentation.4618/
https://wranglertjforum.com/threads...ice-manuals-fsm-technical-documentation.4618/