Engine swap issue?

Tiny
JIM TRENTON
  • MEMBER
  • 1995 JEEP WANGLER YJ
  • 4 CYL
  • 4WD
  • MANUAL
  • 230,000 MILES
I replaced my 95 YJ engine with a 98 YJengin and now the no start symptoms are no check engine light, Fuel gauge pegged above full. No fuel in fuel rail. Fires using starting fluid. I replaced the Crank position sensor, Pickup coil, fuel pump and computer capacitors. I am not a mechanic; I am only guessing maybe replace computer to a 1998 and then replace wire harness because computer plugs are diffrent. Any ideas are greatly appreciated.
Wednesday, October 30th, 2024 AT 7:24 AM

37 Replies

Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 50,820 POSTS
Usually when this happens it is because of one of the engine wiring harness grounds are not connected. I would use a flashlight to go over the grounds again to make sure all connections are clean and tight. The one I am talking about is behind the distributor. Here is the engine and PCM wiring diagrams so you can see how the system works, and I have marked the ground I need you to check. Also, I would make the MAP sensor is plugged in and mounted, if the PCM does not see vacuum it will not turn on the fuel pump. Also, let's run the codes to see what are stored.

https://www.2carpros.com/articles/jeep-diagnostic-trouble-codes-for-car-built-on-or-before-1995-odb1

Check out the images (below). Please upload pictures or videos in your response of any problems so we can see what to help you with.
Images (Click to make bigger)
Thumb
Thumb
Thumb
Thumb
Was this
answer
helpful?
Yes
No
Wednesday, October 30th, 2024 AT 5:02 PM
Tiny
JIM TRENTON
  • MEMBER
  • 23 POSTS
Ken, Thank you. I already have cleaned that ground wire attachment earlier. I def. Will check the wires on the MAP sensor. I can not check codes because my check engin light hasn't came on after this swap. Check engin light stays off and Ebrake dash light is permently on when key is turned on. I also hot wired gas pump relay and still no gas comes to rail. So I will do all you said and I will let you know. I do this when I am able.
Was this
answer
helpful?
Yes
No
Thursday, October 31st, 2024 AT 6:05 AM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 50,820 POSTS
Sounds good Jim, have a good weekend.
Was this
answer
helpful?
Yes
No
Thursday, October 31st, 2024 AT 1:49 PM
Tiny
JIM TRENTON
  • MEMBER
  • 23 POSTS
I looked today and MAP sensor wire connection was on properly and tight. The tube on it was attached on MAP sensor and other end was on the intake manifold at the carburetor. I found a rusty connection on the driver side rear top engine that I will take apart and clean with a wire wheel on a Dremel, soon. I will keep you posted. Thank you for your help, time and patience.
Was this
answer
helpful?
Yes
No
Thursday, October 31st, 2024 AT 3:29 PM
Tiny
JIM TRENTON
  • MEMBER
  • 23 POSTS
The rusty connection is a copper braided ribbon going from the top rear of engine to firewall. The other end of that ground on firewall looks clean and good as I did clean that earlier. It's the end attached to engine that is rusted up.
Was this
answer
helpful?
Yes
No
Thursday, October 31st, 2024 AT 3:32 PM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 50,820 POSTS
The connection should be cleaned if it is rusty, this might be the problem.
Was this
answer
helpful?
Yes
No
+1
Friday, November 1st, 2024 AT 10:53 AM
Tiny
JIM TRENTON
  • MEMBER
  • 23 POSTS
I did clean these today but haven't tried starting it. I'll put my battery on it tomorrow and try starting it.
Was this
answer
helpful?
Yes
No
Friday, November 1st, 2024 AT 3:06 PM
Tiny
JIM TRENTON
  • MEMBER
  • 23 POSTS
You can see 2 of the 3 grounds I cleaned today. One pic was a duplicate and the other not related to this project. I'm not good with using my phone.
Images (Click to make bigger)
Thumb
Thumb
Thumb
Was this
answer
helpful?
Yes
No
Friday, November 1st, 2024 AT 3:20 PM
Tiny
JIM TRENTON
  • MEMBER
  • 23 POSTS
I put my battery on my wrangler, and it still won't fire. Symptoms remain the same, No check engine light, no start up. The same things came on. Ebrake light, Fuel gauge pegged on full, lights work, radio works, heater fan works.
Was this
answer
helpful?
Yes
No
Saturday, November 2nd, 2024 AT 9:01 AM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 50,820 POSTS
In the last image it looks like the ground is not good like the plastic insulator is getting in the way of the connection. Let's see if you have power to the ignition coil when the key is on? This guide will help:

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

Test either side of the ignition coil to see if the test light illuminates.
Was this
answer
helpful?
Yes
No
+1
Sunday, November 3rd, 2024 AT 11:08 AM
Tiny
JIM TRENTON
  • MEMBER
  • 23 POSTS
I will try that, maybe today.
Was this
answer
helpful?
Yes
No
Monday, November 4th, 2024 AT 4:54 AM
Tiny
JIM TRENTON
  • MEMBER
  • 23 POSTS
Ken, Can I use a HF Multimeter to do this or do I need the test light for this application? Thank you. If I need the test light I will have to waite a while to get that. Thank you again.
Was this
answer
helpful?
Yes
No
Monday, November 4th, 2024 AT 5:36 AM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 50,820 POSTS
You can use a voltmeter no problem. Let me know what you find.
Was this
answer
helpful?
Yes
No
Monday, November 4th, 2024 AT 9:36 AM
Tiny
JIM TRENTON
  • MEMBER
  • 23 POSTS
I will thank you.
Was this
answer
helpful?
Yes
No
Tuesday, November 5th, 2024 AT 4:31 AM
Tiny
JIM TRENTON
  • MEMBER
  • 23 POSTS
Ken, my multimeter is shot. It will take several days before I can go to Harbor Freight for a new one. I will let you know when I can move forward on this grounding test. Thank you and thank you for your patience with me.
Was this
answer
helpful?
Yes
No
Tuesday, November 5th, 2024 AT 9:51 AM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 50,820 POSTS
No problem, a test light works well too :)
Was this
answer
helpful?
Yes
No
Wednesday, November 6th, 2024 AT 9:06 AM
Tiny
JIM TRENTON
  • MEMBER
  • 23 POSTS
Ken, I am still waiting to go to HF to get that tester. We get payed on Wed. So hopefully soon we can go.
Was this
answer
helpful?
Yes
No
Monday, November 11th, 2024 AT 4:31 AM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 50,820 POSTS
Sounds good, we can work together to fix it.
Was this
answer
helpful?
Yes
No
Tuesday, November 12th, 2024 AT 10:40 AM
Tiny
JIM TRENTON
  • MEMBER
  • 23 POSTS
Thank you, Ken, for your patience.
Was this
answer
helpful?
Yes
No
Wednesday, November 13th, 2024 AT 5:33 AM
Tiny
JIM TRENTON
  • MEMBER
  • 23 POSTS
Ken, we haven't made it to the store but I ordered a test light online.
Was this
answer
helpful?
Yes
No
Monday, November 18th, 2024 AT 6:12 AM

Please login or register to post a reply.

Related Engine Replace/Remove Content

How to Remove an Engine
VIDEO
How to Remove an Engine
In­struc­tional re­pair video
VIEW MORE