3.4 swap into 1985 Jeep Cherokee questions?

[cardana24]

I bet the tieing of the wires together helped contribute to your no-start issue. Just think, you might have had this fixed a week or so ago had you just soldered all the wires in the first place.

Thank you Debbie Downer

[Canyonero]

So, question: Would you rather have paid $500-$700 for a custom harness and not had to do any of that wiring and troubleshooting?

[cardana24]

So, question: Would you rather have paid $500-$700 for a custom harness and not had to do any of that wiring and troubleshooting?

No. I wanted to figure this out for myself and other people who wanted to do the swap with the stock harness. I am sure the custom harness would have saved me some headaches but I also learned alot about all of the wires and how the control certian parts of the engine. Plus other than pluging the sensors in there really is not that much wiring involved once you figure out what is needed and what is not. Right now my engine bay is a huge mess of wires but I will take some pics once I get it cleaned up.

When it was running the other night it did not idle very well...so I am sure there will be some questions to follow regarding that.

I wired my MSD tach adaptor last night, and I wired it as a voltage set up...does anyone know if that is correct? Through looking at the wiring it looks as if my tach had a negative feed that's why I wired it that way.

[Canyonero]

My truck had been down for over a year, and I wanted it back. I was just throwing money at it, and it does run now... I think I would have ended up with a cleaner install if I would have done it myself. So next time, I will.

Congrats on your accomplishment. My trooper wasn't running perfect right away either, but it was a good feeling knowing I could go in the garage, turn the key and have it fire right up.

I wouldn't rule out your injectors. You could still have one clogged. I had one stuck wide open and was pumping raw fuel out the exhaust. Also had my O2 sensors connected backwards. Ran like crap when it went to closed loop. Ooops.

[cardana24]

My truck had been down for over a year, and I wanted it back. I was just throwing money at it, and it does run now... I think I would have ended up with a cleaner install if I would have done it myself. So next time, I will.

Congrats on your accomplishment. My trooper wasn't running perfect right away either, but it was a good feeling knowing I could go in the garage, turn the key and have it fire right up.

I wouldn't rule out your injectors. You could still have one clogged. I had one stuck wide open and was pumping raw fuel out the exhaust. Also had my O2 sensors connected backwards. Ran like crap when it went to closed loop. Ooops.

I understand why you got the harness...and believe me I thought about it, but now looking back on it I am glad I didn't. Now I pretty much know where all of the wires go coming out of the ecm and what there purpose is...it was a learning experience.

As for the running thing, this engine has only run for a total of a few minutes and that was just one time. I will crank it again when I have my wiring protected. Right now I still have wires every where and open exhaust in the engine bay so I am not trying to melt stuff. Hopefully tonight I can get all of that protected and crank it up again. Also I need to change out the factory intake set up. the 90* elbow coming off of the TB is too long so it sits on top of the radiator, so I ordered and intake off of ebay that 90's right off of the TB so I am hoping that works a little better since it fits in front of the radiator.

What do you mean you had your 02 sensors hooked up backwards? I don't think my wiring will stretch that far. Can you explain this a little better so I can check it on mine.

[Canyonero]

What do you mean you had your 02 sensors hooked up backwards? I don't think my wiring will stretch that far. Can you explain this a little better so I can check it on mine.

Well, I believe that my harness was assembled wrong. The logical way to hook it up was backwards... You're probably fine.

Get some pictures up! I like to see messes too. Makes people appreciate just how much work went into a project. I drove around for a couple weeks with my ECU on the floor and wires pouring out my glovebox. Got a few comments.

[cardana24]

Well, I believe that my harness was assembled wrong. The logical way to hook it up was backwards... You're probably fine.

Get some pictures up! I like to see messes too. Makes people appreciate just how much work went into a project. I drove around for a couple weeks with my ECU on the floor and wires pouring out my glovebox. Got a few comments.

I'll see what I can do but I already cleaned a lot of it up and tucked away the fuse box next to the battery.

As for my ecm I am keeping it in the engine bay. I would have to extend every wire to put it in the vehicle. So I picked up a plastic ecm box from a mid 90's luminia, so I hope I can use that to mount my ecm in. I'll take pics if it works out.

[Canyonero]

That's what I should have done. There is plenty of room in the engine bay. My original ECU was in the center console. No way would my harness reach there, so I had to sacrifice the glove box.

[cardana24]

For where I want to put the ecm (upper right hand corner) I don't think the lumina ecm box is going to work...it's too big and bulky.

I took a few pics so you guys can see where I stand. The first few pics I had already cleaned the wires up a lot, but I did not take pics when they were at there worst, so there are a few before and after pics. I hope to crank the jeep again tonight. On another note, it looks like my hood will not close with out modification...so rather than shiming it up higher or some other mod I am going to probably get a cowl insert Questions and comments are welcome.





Also the stock intake was sitting on top of the radiator so I found this intake on ebay. I only put the first pipe on to make sure it will fit, but it has two other pipes that come with it as well. I am going to modifiy one of the other pipes so that my filter sits behind the opening in the front for the stock intake. Then I am going to build a heat shield around that to try to keep the IAT's down.

[ssterlingb]

Cograts!! I just got back into town & checking emails. Looks good. Glad you got it up and running!

[cardana24]

Thanks man, hopefully I have a lot of helpful information for you.

I have all of my gauges working now too, except for my voltage gauge. Where should I be getting that signal? Is it the wire coming out of the plug on the top of the alt?

[ssterlingb]

The camaro gauge just reads power from the circuit feeding the entire cluster from the fuse box. I'll have to check to see where the jeep is hooked up. You probable just need to connect to an available 12+ in the dash.

[cardana24]

I don't have my jeep wiring diagrams with me right now, I'll check it when I get back home.

So where does the wire coming off of the plug from the alt. go?

[ssterlingb]

On the camaro diagram, there are two wires, the battery & another smaller red that is the "Turn On Input (Power Up For Regulator)" It appears to come from a solid state indicator request built into the camaro gauge cluster. I think it goes from the circuit feeding the cluster through a 470 ohm resister to the alternator. I think it tells the alternator when to charge. Might be worth checking with some others to verify.

[Canyonero]

Do you have that alternator wire hooked up anywhere? I don't know where it needs to go on the Jeep, but if it isn't hooked up the battery won't be charging. My Trooper used the same connector, so it wasn't a problem for me.