Engine swap issue?

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.

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.

Sounds good Jim, have a good weekend.

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.

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.

The connection should be cleaned if it is rusty, this might be the problem.

I did clean these today but haven't tried starting it. I'll put my battery on it tomorrow and try starting it.

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.

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.

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.

I will try that, maybe today.

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.

You can use a voltmeter no problem. Let me know what you find.

I will thank you.

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.

no problem, a test light works well too :)

Ken, I am still waiting to go to HF to get that tester. We get payed on Wed. so hopefully soon we can go.

Sounds good, we can work together to fix it.

Thank you, Ken, for your patience.

Ken, we haven't made it to the store but I ordered a test light online.

Okay, let me know how the tests go.

I will Ken.

Ken, I hope you have a nice Thanksgiving. Do not reply this week since it is a Holliday. I hooked up my tester and it showed green until I had her turn the Jeep over. The red positive light flashed one time. We did this twice with the same results both times. Red and Black clips went on battery connections, small ground clip went on ground bolt on engine block then I touched probe to exit stud on coil. I hope this gives you the info you need. If I need to do anything else, I will. Thank you, Jim

We have gotten off-topic on this post. Could you please start a new one with the current problem? please post your new question here, you must be logged in.

https://www.2carpros.com/questions/new

Cheers, Ken

I am unable to continue because trying to put in my info in sight given to me, it will not allow me to put in the model of my Jeep. I cannot move forward on this because now all communication has been cut off.

The site seems to be working fine, can you clear your cookies?

I will Google how to do that. thank you

I deleted cookies through Crome, I still can't enter my model number. I will stop in the phone store and see if they can do more than I was able to. I'll let you know after I find out. Thanks Ken.

It must be something on your end because no other complaints have come in. Can you try it on a desk or laptop? Did you have this problem before?

I didn't have this prob until I tried reposting my question in the link you sent and not being able to put in my Jeep model is the only trouble I am having. My cell phone is the only way I have to do anything. I will see what my phone store can tell me when I can get there. I'll let you know when I find out anything. Thanks Ken

Just jumping in here. You say you replaced the engine in your 1995 Wrangler with one out of a 1998 Wrangler, correct? Now you have a no start. Although those engines are based on the same block design, they are not the same engine internally. 1995 would have been the last year for the early version of the 2.5 4cylinder and the AMC designed computer controls for it. 1998 used a different control system with the timing and computer coding different. For a bolt in install in the 95 you can use the 91-95 engine.

Steve, I was afraid of this. When I bought the good used engine, I was told it was a 1995 but recently I checked a number on the block, and it is a 1998 block. Can the computer be changed to a 1998 computer and if so, will it need a new wire harness because the computer plugs are different? Thank you for this info.

You would need to change a lot to make it work because the modules are all linked. The PCM uses codes stored in the BCM for the security system and both are tied to the dash as well. So swapping one means you need to swap them all. It's one of the "fun" things with doing engine swaps these days. Especially Chrysler products because of all the times they have changed hands and control hardware. It becomes even more fun when they don't show the changes. When they built the new modular engines in 02 they changed things 4 different times but used the came basic engine, just made them incompatible. With Jeep it was worse for years because of all the different engines they used. You need to have a scorecard to track all the changes.

Thank you Steve. I think i will just sell it and move on. I am sure I lost money on this but it is what it is. Thank you for your insight.

You are not the first to get caught by their trap. There were a number of shops that have gone through the same thing, and I don't know how many DIY folks as well. It's one of the reasons why I don't even try swaps unless it's an identical engine. Many times, I just order a crate engine and ship in the old one as a core. Less aggravation that way. Hope you don't lose much. Sorry the news isn't better.

Thank you Steve for everything.

You are welcome.