Extended Idle 97-01 Install

[vetteboy]

I would think that you could add a variable resistor in series with the TPS (between the matting female and male pin C at the TPS / wiring harness connector) to do it. The only problem is finding the right variable resistor (potentiometer). Might take a mini powerstat to do it well.

It would take some experimentation. Sounds like a Mod-section topic now.

Hmm...perhaps. In thinking about it a little more, I'm pretty sure the IAC uses a stepper motor which would be a little trickier to take manual control of. There's a box that does exactly what I'm describing that'll go from 0-3000 RPM with pushbutton control but it's $200+ and I'd rather find something I can do myself.

I'll try probing some sensors today maybe and see what I can come up with.

 

[Ecomike]

I took some ohm meter readings once on my Renix, 87 TPS while it was attached and read 4.28 to 6.66 K-Ohms from B to C (according to my notes).

You might go to Radio Shack and pick up some resistors, 10, 100, 500, 1000 ohms, temporarily install each one and see what it does to the idle speed. From that data you could determine a range you need for the variable reisistor.

 

[vetteboy]

Would the TPS have an effect on things though? I always kinda thought it was more of a passive sensor that helped decide the injector duty cycle. If you "trick" the ECU into thinking the throttle is open more than it actually is, and it starts dumping more fuel in, I think it would either result in a rich mixture and not work as well....unless it adjusts the IAC to compensate for it. Hmm.

Most people would just run a bike shifter cable to the throttle arm at this point and call it good.

 

[Ecomike]

Would the TPS have an effect on things though? I always kinda thought it was more of a passive sensor that helped decide the injector duty cycle. If you "trick" the ECU into thinking the throttle is open more than it actually is, and it starts dumping more fuel in, I think it would either result in a rich mixture and not work as well....unless it adjusts the IAC to compensate for it. Hmm.

Most people would just run a bike shifter cable to the throttle arm at this point and call it good.

The TPS tells the ECU where your foot is on the gas peddle! The extra resistor will lie to the ECU for you and tell it you want more RPMs. The ECU will adjust the fuel and the IAC together to increase the idle. I learned this the hard way when I had ground problems that added to the TPS resistance via the ground leg, Pin C, and made mine idle to fast when the ground got intermitently loose!

My experience is with the older Renix Jeeps, 1987 in this case, but they are similar enough in later years that it should work on the new models as well, unless they made the newer computers smarter, which I doubt. Just try it.

But now that I think more about it you may need to install it on the two C gound pin connections, and / or recalibrate the TPS at a higher voltage first with the Variable resistor at a dead short first to be able to use it in the B pin connection.

 

[JEEPZZ]

I know that it doesn't stay active when you are in gear. It only works when in neutral or park. What I was wondering is if you could wire it up so the extended idle was activated everytime when you are in park or neutral without using a switch. Would there really be a problem or any issues with this besides sucking more gas. Sorry I wasn't so specific in my original post.

Just ground pin 12 and the system will always be active without the need for a switch. Doing this will kick the idle up everytime you go into neutral or park, just like leaving the switch in the constant 'on' position.

 

[JEEPZZ]

(rere97)Can anyone provide part numbers for this bezel and switch?

The foglight switch and the ext idle switch have the same part number, only the bezel label is different. I'm sure someone will post the part number before I get a chance to dig them up, again.

 

[klennop]

Just ground pin 12 and the system will always be active without the need for a switch. Doing this will kick the idle up everytime you go into neutral or park, just like leaving the switch in the constant 'on' position.

Are there any drawbacks/problems to doing it this way though?

 

[JEEPZZ]

Are there any drawbacks/problems to doing it this way though?

Other than the obvious (not being able to manually control it), I don't see a problem with it.

 

[krelja]

Extended Idle Switch - 56008728.

4-Switch Bezel - 4897505AE.

Note that these numbers are for '97 and up only.

I got both of mine from allchryslerparts.com. Ran about $60 or so for both, IIRC.


Yes, you can get just the switch by itself. Of course, if you ever intend to wire front fogs back in again it might be handy to keep the existing one.

you can also get the stuff @ www.jeepsareus.com as well oh yeah and for some reason when I searched for the part I needed to keep the . on the end to otherwise it would say no parts found

 

[rpyne]

The foglight switch and the ext idle switch have the same part number, only the bezel label is different. I'm sure someone will post the part number before I get a chance to dig them up, again.

No one has. The switch I can find, but I haven't been able to find the part number for the bezel.

I'm still working on figuring out the wiring needed for my 88.

 

[Ivan]

No one has. The switch I can find, but I haven't been able to find the part number for the bezel.

I'm still working on figuring out the wiring needed for my 88.

4897505AD - 4 Slot Switch Bezel for 97's and newer....
I got mine online at one of those All Chrysler Parts websites.....

 

[JEEPZZ]

4897505AD - 4 Slot Switch Bezel for 97's and newer....
I got mine online at one of those All Chrysler Parts websites.....

He was talking about this one for the pre97 models:

No one has. The switch I can find, but I haven't been able to find the part number for the bezel.

I'm still working on figuring out the wiring needed for my 88.

You're going to have to get creative on wiring it up since 92 & older were not set up for the ext idle circuit.
If you've got one of your 2 slots open on the bezel (4 actually, 2 per side) just throw the switch in the unused slot. Don't worry about the ext idle labeled bezel.

 

[rpyne]

You're going to have to get creative on wiring it up since 92 & older were not set up for it.

I had it all figured out for my 87 2.5, but I haven't got it yet for my 88 4.0. On the 87, it was as simple as using the same system used for the A/C which activated a solenoid that opened up a vacuum line to raise the idle.

I think I can do it in a similar fashion on the 88 using a signal to the ECU that detects the A/C calling for the compressor to turn on. Just haven't yet had good enough weather to work outside when I had time to experiment.

 

[XJesse]

Any ideas of how to add extended idle to a 97 4.0 with a 5spd? I am considering adding a wire to the pcm 12 pin but am hesitant because i have no idea if it would work or possibly screw something up.
any info would be helpfull. especiallly in regards to adding a wire to pcm 12.

 

[Blaine B.]

Just curious - does a 95 have the "power steering pressure sense switch?"

I don't see any wires running to my power steering pump......

 

[JEEPZZ]

Just curious - does a 95 have the "power steering pressure sense switch?"

I don't see any wires running to my power steering pump......

The power steering switch replaces the ext idle circuit only on the 4 cyl motor.

 

[Blaine B.]

Ah. OK....

It jumps the RPM's up when the wheels are turned at idle?

 

[JEEPZZ]

Ummm no. From what I've read, it's a completely different circuit in the 4 banger.

 

[RWB214]

Any ideas of how to add extended idle to a 97 4.0 with a 5spd? I am considering adding a wire to the pcm 12 pin but am hesitant because i have no idea if it would work or possibly screw something up.
any info would be helpfull. especiallly in regards to adding a wire to pcm 12.

I've been wondering the same thing: Would this work on my 99 5 spd? In addition, why not just use an aux switch that connects Pin #12 to ground?

 

[RWB214]

To whom it may concern I have confirmed that this mod will not work on a 99 5 spd. The hole for pin 12 was blocked to keep moisture out so I had to dismantle the connector and dremmel the plastic out. Putting the connector back together was a PITA, but I did it and with the engine idling I inserted a paper clip into pin 12 and connected it to ground. Nothing. I assume that even if the PCM's are the same(auto or manual), it requires some input from the auto transmision in order for the Ext Idle function to work.