Mixed feelings on JK ETC

[Marky]

OK, this is going to be a long one... Since the JK's have electronic throttle control, it's impossible to add a simple secondary throttle control to make rock crawling easier. What we've been doing is "tapping" the gas pedal which causes the computer to rev up the engine and then slowly allows it to come back down (essentially using the computer and engine tourque to keep our RPM's up) - then repeat. It's not a perfect solution by any means but once you get the hang of it it can be done. I've been watching Offroad Engineering's EHT-300. (http://www.4x4rockshop.com/Scripts/prod ... duct=13640) for a while now. It installs in line with the gas pedal and gives you a hand-held throttle controller. The website says it "allows you to control your vehicle's idle RPM electronically". Sounds great. I finally bought it and installed it the other day. I'm not so sure it's so great though.

First of all, it doesn't "control your RPM's", it merely adds a little gas without any regard for your RPM's. As terrain changes, it does not alter anything. "Unloaded" the RPM's will skyrocket since it's not smart enough to actually monitor RPM. While setting it up I found that it either did nothing, or revved up the engine to 2500 RPM or more. I could not set a lower idle speed. It claimed you could set a "preset idle" for anywhere between normal idle (about 600) and 3000. Not true, or at least impossible. I called the company and they told me to set it with a load. I asked them how I was supposed to turn the little set screw mounted above my gas pedal while driving down the road (no answer.) In either case they said it would be very sensitive unloaded and would give much better results during actual use. I did finally drive it up my driveway a few times and it does work, but as soon as you push the clutch in, the RPM's go crazy. Add to that the optional "high idle" button mounted on the dash and it's a catastrophe waiting to happen. There seems to be no rhyme or reason as to which supersedes the other. With the handheld controller off, sometimes the high idle button works and sometimes it doesn't. This evening I turned the high idle button on which caused the rpm's to jump right up, adjusted the handheld throttle to allow it to carry me up the driveway, got to the top and turned off the handheld controller just as I put in the clutch. I expected the engine to return to normal idle speed. Instead the engine jumped up to 4500 RPM's with the power switch off because we forgot to turn off the high idle switch - which incidentally was just set to 2000 RPM's *unloaded* a few minutes before.

It seems like what's happening is the Jeep's computer is sensing something isn't right and is fighting the new controller unit. It's acting really strange and I'm not sure I like what's happening with it. That being said, I think I mostly understand its quirks and, to be fair, you're only supposed to use it in 4lo offroad. I'm thinking of trying it on the trail before ripping it out and getting my money back, but I'm really unsure about this unit right now. I'm also thinking of calling the company back and suggesting that maybe I got a bad unit because I can't believe a company with "engineering" in their name would put out a product so poorly engineered.

So that brings me to my question... has anyone tried one of these yet (or knows someone who has) and how has it worked out? Are my results normal? Thoughts?

[ZAEDOCK]

Jeebus. Sounds like you got the beta model.

I don't like messing with new engine controls. To raise the idle a bit, I would probably try wiring a switch to the A/C compressor clutch power and when you want a higher idle for crawling, turn the A/C on (to which the computer raises the idle), and then flip the toggle so the clutch doesn't engage.

[nostaw]

Sounds like they are trying to trick the computer by simulating the gas pedal being slightly depressed?

Sounds like their control doesn't map the way Jeep's throttle control actually works well... Problem with electronic throttle is you don't really know how the throttle is adjusted in proportion to the pedal position, which is really just a "suggestion" to the computer, which will adjust the throttle based on multiple parameters.

I'd send it back and stick to tapping...

JW

[Baseshakers]

weird thought, could you hook up a cable to pull on the gas pedal? for TJs and older we obviously just run the cable (bike shifter) all the way to intake, but i know that's not an option on a JK. i wonder if you could run a cable out to the engine bay, curve it back around and attach it to the firewall right next to the gas pedal. then you could pull on the pedal. anyway, no idea if there's enough space under there but just throwing it out.

[Frank]

Yea ! Lets invent some more useful stuff that no one wants. Sounds like that gizzmo will be a hand full on and off the trail. FjR68