2.5 cruise control question

[jteckmann]

Hi all. Sorry if this has been asked and answered a bunch, but couldn't find the exact info I was looking for when I searched.

 

I have an '86 2.5, TBI, 4sp. Next junkyard trip, I want to pull a factory cruise set up and install it in my ride. Main question: can I pull the parts off any Renix era manual tranny XJ/MJ, or do I need specific parts off another 2.5? i.e., does the "brain" from a 4.0 work on a 2.5?

 

slightly related question: when I get the control switch, it will likely have wiper delay settings on it. My current wipers are not delay. Is there an additional part/relay I need to pull to transfer that feature over?

 

Thanks in advance.

[Wildman]

I might be wrong........but I don't think the 2.5 ever had cruse control :hmm:

 

If I'm wrong.......someone jump in here.

 

The ECU from a 4.0 Will Not work for a 2.5 :no:

 

Your injector(s) *on a 4.0, the six of them* are pulsed from the ECU, plus, the idle is controlled from the ECU, and the ignition.

 

Here's a topic on adding cruse control you might want to read up on.......

 

viewtopic.php?f=2&t=18358&hilit=cruse+control

 

The delay wipers is just a matter of adding a control box in the wire connector, just at the base of the steering column, behind the knee panel and of course, you do need the stalk with the intermediate wipers, including the smart switch inside the column. It might be easier to swap out the entire steering column than to pull the column apart in the JY. Plus, you just might end up with a tilt column :brows:

[jimoshel]

2.5 did have cruise. It was called cruise command and used GM components. Another reason to get the entire steering column.

[Wildman]

Thanks for the info jimoshel ;)

 

Then if the OP want curse in his 2.5, he'll need to pull it from a 2.5 donor, not a 4.0 donor.

[Geonovast]

Cruise has NOTHING to do with the ECU Pre-91.

[jimoshel]

I didn't actually compare components.Just popped the hood and looked. On the surface they look identical. Also the manual does not list any differences between them. Check back tomorrow night and I'll have more definate info.

[1986Comanche]

The ECU from a 4.0 Will Not work for a 2.5 :no:

 

Your injector(s) *on a 4.0, the six of them* are pulsed from the ECU, plus, the idle is controlled from the ECU, and the ignition.

 

I don't think he's talking about the computer for the engine. He's talking about the computer or control box for the cruise control. It looks like this:

 

[jteckmann]

I don't think he's talking about the computer for the engine. He's talking about the computer or control box for the cruise control. It looks like this:

 

 

Yeah, that's the part I'm wondering about. (sorry - should've been more specific) Will one from a 6cyl work on a 4cyl?

 

Thanks for the info on the wipers, Wildman. That's my goal - try and get a whole new tilt-column and hopefully a 3-spoke steering wheel if I'm lucky. But the boneyards around here have been pretty dry lately.

[jimoshel]

The speed sensor, servo and control switch on a '84 XJ 2.5, A '85 XJ 2.5 and a '87 XJ 4.0 are identical. These are the only units I have to compare with. The regulator, That's the yellow box, I don't know about. The '84 and '85 are the same. I have them out and compared them. The '87 is still in the XJ and I didn't have time to get it. What I do when wondering if something will interchange is go online to a parts store. and check the stock, part numbers. If they're the same it will interchange. Also there are 3 adjustments on the regulator to set. This is a personal opinion but I think the 2.5 and 4.0 regulators will swap by use of these adjustments.

Also the speed sensor,servo and control sw on S10's and some of the GM cars will also work. Regulator, don't know but doubt it.

[jteckmann]

The speed sensor, servo and control switch on a '84 XJ 2.5, A '85 XJ 2.5 and a '87 XJ 4.0 are identical. These are the only units I have to compare with. The regulator, That's the yellow box, I don't know about. The '84 and '85 are the same. I have them out and compared them. The '87 is still in the XJ and I didn't have time to get it. What I do when wondering if something will interchange is go online to a parts store. and check the stock, part numbers. If they're the same it will interchange. Also there are 3 adjustments on the regulator to set. This is a personal opinion but I think the 2.5 and 4.0 regulators will swap by use of these adjustments.

Also the speed sensor,servo and control sw on S10's and some of the GM cars will also work. Regulator, don't know but doubt it.

 

Thanks, jimoshel! I really appreciate it.

[jimoshel]

Addendum, Correction, Cruise control components from '84XJ thru '89XJ and '86MJ thru '89MJ are identical. Regardless of engine, 2.5, 2.8 and 4.0 and or transmissions. The control stem from '80's S10 is identical to Jeep. That's where Jeep got them from, GM.The speed sensor from the GM S10 2.8 will fit all Jeeps. The GM servo will work but the electric plug needs to be replaced. The pins are different. The GM regulator, I have no idea. Might get to it later and find out. Altho I doubt it. I believe the entire S10 steering column might intercahnge. Ask yer friendly JY man to check his Hollander.

'

[Wildman]

The ECU from a 4.0 Will Not work for a 2.5 :no:

 

Your injector(s) *on a 4.0, the six of them* are pulsed from the ECU, plus, the idle is controlled from the ECU, and the ignition.

 

I don't think he's talking about the computer for the engine. He's talking about the computer or control box for the cruise control. It looks like this:

 

 

Yea, I seen the word "brains" and mine wasn't working :doh:

 

Brains = Computer = ECU........this time I was wrong :oops:

 

jimoshel......you grabbed the handle on this, the floor is your :bowdown:

[64 Cheyenne]

Here's my question about doing a cruise control swap. On my 89 XJ, I plan taking the cruise out of it and and swap it into my 87 MJ. Only thing is, nowhere have I seen a 2 piece speedo cable on it. Where is this speed sensor mounted, anybody got a pic of it?

The 89 was fully intact under the hood, I pulled vacuum hoses lots of other small stuff, I traced the speedo cable, looks 1 piece to me. :dunno:

[Wildman]

The speedo cable splits off behind the cluster, inside the dash. With the pick up sensor, and the "upper" cable (short) going to the speedometer.

[64 Cheyenne]

So is there a sensor located there, that has wiring that goes to the speed servo or is another speedo cable attached to the servo?

[Wildman]

Main speedo cable, Sensor with wire to that stupid yellow box I forgot, and short cable to the back of the cluster. All in line.

[jteckmann]

So is there a sensor located there, that has wiring that goes to the speed servo or is another speedo cable attached to the servo?

 

The sensor is located in between the two speedo cables, with wires going over to the control module.

 

Sorry I don't have a pic to post, but it's a black disc. Follow the speedo cable where it enters the cab, and you'll find it about halfway up the steering column, behind the instrument cluster.

 

 

And once again, thanks jimoshel - that's great info.