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Ok Gang... I heard and listen to a bunch of you that are not quite up to par with wires and doing this mod... Well I sat down and re-drew the wiring layout using the actual parts and so you can see its rather easy to do... so here you go... hopefully this will help you all out a bit! http://forum.mopar1973man.com/attachment.php?attachmentid=101&stc=1&d=1261188730 http://forum.mopar1973man.com/attachment.php?attachmentid=102&stc=1&d=1261196659

First off let me explain the reason for high idle functions. The 24 valve Dodge Cummins trucks tend to burn must cooler because of the extra valves in the head. But in the cool winter time temp it's possible for the combustion temperatures to fail low enough to cause tar formation on the valves and cause them to stick. This in turn will bend the pushrods cause some serious damage. Dodge has a TSB bulletin to correct this problem by flashing the ECM and enabling the existing software for high idle. http-~~-//www.youtube.com/watch?v=umXz_xGxank http-~~-//www.youtube.com/watch?v=P0Ah9nK3ahc http-~~-//www.youtube.com/watch?v=il7iJCKfmaE Design Reasons The reason for designing the high idle switches was to gain control over the high idle software that Cummins provided. The software works completely automatically and there is no control for the driver of the vehicle. So if the software senses that the manifold and coolant temps are cold enough it will start the proper software and start high idle. But there is several other reason people need high idle feature and need to be able to enable at temperatures above program values. Like myself I'm a volunteer with the local Fire Dept and EMS Crews so the fact my truck sits along the highway with emergency lights, hazards, head lights, etc. The alternator can't keep up so high idle is enabled. This way the exhaust temps don't fall to low and the alternator is keeping the batteries charged. Operation Cold Engine Start (Coolant <140°F - Outside Temp > 32*F) Turn on the IAT fooler and select normal high idle. Now start your engine. With in about 2 minutes the high idle should start. Once the high idle starts turn off the IAT fooler and allow the ECM to monitor the IAT temperatures. As the engine warms up to 170°F it will cancel on its own and idle normally from that point on. Cold Engine Start (Coolant <140°F - Outside Temp < 32*F) Turn on the IAT fooler and select 3 cylinder high idle. Now start your engine. With in about 2 minutes the high idle should start once it get to 1,200 PRM's the 3 cylinder mode with begin. Once the high idle starts turn off the IAT fooler and allow the ECM to monitor the IAT temperatures. As the engine warms up to 170°F it will cancel on its own and idle normally from that point on. Warm Engine Start (Coolant 140°F-170°F) You can start the high software with a warm engine. At this point you need to use both the ECT fooler and IAT fooler. Select the proper high idle mode for your weather conditions as in cold start procedure. Once the high idle starts turn off the IAT & ECT foolers and allow the ECM to monitor both ECT & IAT temperatures. As the engine warms up to 170°F it will cancel on its own and idle normally from that point on. Forced High Idle Turn on both ECT fooler and IAT fooler have it set for normal high idle. Start the engine and allow the high idle to start. Once the high idle starts turn off the IAT fooler but leave the ECT fooler on. This will allow a forced high idle that never ends. To cancel it just turn off the ECT fooler and it will cancel. WARNING: In this mode of operation the ECT sensor is completely disabled. There is no way of monitoring engine temperatures. Becareful and alert to changes in the engine at this point. If you have a exhaust brake DO NOT activate it in this mode. Enhanced Warm Up If you have a exhaust brake you can use it will both 3 cylinder high idle and normal high idle. But be sure to turn off the ECT fooler when the high idle begins this will allow for normal cancellation. This will push the EGT temps up to about 800-850°F and warm the engine rapidly in under 10 minutes you should have 170°F of coolant temperature. Other Notes and Warnings... [*] DISCLAIMER: I'm NOT responsible for any damages to your vehicle from using this information. [*]WARNING: Do not activate any of the IAT or ECT foolers while driving the vehicle this will have a direct impact on performance and may case serve engine damages. Alway be sure that all foolers are turned off before moving the vehicle. [*]Once the high idle cycle has completed during this key cycle it is not possible to re-start high idle a second time on that key cycle. You must shut down the engine and restart to force a second high run. Now if you cancelled manually by tapping the throttle you can resume the high idle again by turning on the IAT and/or ECT foolers. [*]3 Cylinder high idle is going to sound rather weird like the engine is falling apart this is totally normal. This mode of operation skips or shuts down 3 cylinders from getting a injection pulse. These 3 dead cylinders produce a load on the engine and cause it to warm up rapidly. [*]Even with both IAT and ECT foolers off the high idle software can start normally if the conditions require it as posted in the TSB by Dodge.

Here is a new high idle video I recorded... Showing many new tidbits...

Just like the title says... it's summer and hot here. I've only owned the truck since spring when it never dropped below 40 out, I would like to figure this out BEFORE the cold weather hits this year if possible. I go to the gym 4-5 times a week and it's only a 2 mile drive so I am considering leaving my truck run while working out to prevent possible problems due to frequent short trips and not warming up properly. If I don't have it I will probably do the high idle mod so I can keep the motor warm and EGT's above 300. My truck stays fairly cool even in 80-90 degree weather at idle... I rarely see EGTs over 270 once it's sat for a minute or two, no matter how warm the motor is. Don't know if that's good or bad

Ok it’s getting to be that time of the year again (COLD) and It won't be long before it's snowing and blowing. So…………. can someone fill me in. Apparently Prowelder has 2 versions of the High Idle Fooler. The Original High Idle Fooler and now the High Idle/MPG Fooler. What’s the difference?

I dont mean to high jack but am I understanding it right when you say dont let it idle long? You say go ahead and start lightly driving to keep build up from forming? And is this build up in the form of fuel in crank case?

I got a chance to meet up with stodg73 and upload the High Idle feature on my truck today after work. Thanks for helping me save $90 that the stealership would have charged, your bada** man! I can't wait to see how it works.Again, I would have bought the breakfast if time wasn't an issue, and I apolagize for the long wait. :)Thanks again, I appreciate it very much!

OK.......... I have a Superchip Programmer, it came with the truck. I put the truck back in stock mode and had the high idle turned on at the dealer it worked fine while in stock mode. I put the tuner back on the truck and the high idle didn't work. Figuring that the tuner screwed something up and already paying $90 for the dealer I just gave up on the high idle.Fast forward to this winter. I decide to just go and have the dealer re turn the high idle on. I make an appointment for this morning and head to the dealer.The service manager comes back and gets me to show me the "flash" has already been done. I tell him yea I know it has, I had it done here. I also tell him that the High idle isn't working.The mechanic says he thinks that he can just flash it again and see if that works, but the service manager over rules him and says NO it may screw something up by re flashing it again and not to do it. He's not sure why it isn't working if the flash is already on the truck.I finally tell him look, you're the Dodge Dealer if you can't tell me why it's not working or what you're going to do to fix it just give me my keys and I'm outta here.

I finished my fooler the day after x-mas. I managed to find a 3 position on-on-on switch for the fast idle and a project box that fit perfectly in my ashtray. My only screw-up was on the label for the "Normal" on the fast idle side (the L doesn't show). In hindsite I wish I would have gone "Normal" on the bottom, "3 Cyl." in the middle and "6 Cyl." on the top; that way both switches would have been down in the Normal position. Today was the first time I tried, even after I drove the truck to NAPA to get a headlamp for my wife's car, it fast idled with the switches in the "6 Cyl." and "123F" positions. I thought this was a one time shot at start up, but for grins I thought I'd give it a try this afternoon. I did not shut the truck off and re-start and it was at operating temperature. I thought it was kinda cool, I was under the impression that I had to restart the truck to get the 6 Cyl. fast idle to re-initiate.

i have my block warmer on a timer. When it's really cold, go out and trip it back on. but i had to leave in an emergency, and it was -18.What happened was it cranked hard, (no big surprise there) and as soon as oil pressure came up, it kicked to 3 cyl idle. it skipped right over the 2 min normal idle and the 20-30 seconds of high idle. i hit the brake to stop it and it ran rough until the normal program kicked it back in.just thought i'd share that, because i didn't know it would do it that way.

I went to the dealer and had them activate high idle but it doesnt work. I used a 56k ohm resistor that Prowelder sent for testing purposes and the water temp was down around 100 degrees. I believe the resistor is doing its job at fooling the truck into thinking that its 32 degrees outside because the grid heater took along time to go out in 60 degree weather. MY ultra-gauge shows me that my tps reads 0.00 for the most part but every now and then it will jump up to 0.39 for a few seconds so im thinking this could be the problem. I have a Timbo apps thats only about a year old and I never really could get all the readings to line up like Tim told me to but he said it really didnt matter if it didnt have a delay in throttle responce. Question is, what do I adjust and how do I adjust it?

i just went out and fired up "Blue" (my truck) its about 8deg out and its gunna take a while to get her warmed up, so i was thinking, rather than a mechanical high idle mod, what if i put the engine under load? would there be a problem with simply applying the parking brake and dropping it into drive? (aside from having the vehicle running and in gear without anyone in it...... but i would be in it so that is a non issue, the only way i would consider leaving it unattended would be if there was a safer system or if i could devise a safer system other than the parking brake) seems to me it would warm up a lot quicker if it were under load and i think that would also solve the problem of exhaust valve "gunk" build up that occurs when a diesel is left to idle for extended periods. anyone have any thoughts on the idea? i decided i needed to edit the original post as i was not conveying my entire thought process, what i added is in bold and italicized .

Well gang... I know a bunch of you have either built your own high idle mod or purchased one through Prowelder or maybe another source. But I know a few of you have had some diagnostic problems in building or have had issues after installing. Well this little write up should walk you through most of it ad figure out what is going on. Ok let get down to tools... You'll need a DVM (Digital Volt Meter) set on ohms. Now lets start with the ECT fooler... Now with the female plug which is the plug that hooks to the ECM we want to measure the ohms at this plug with the fooler in the ON position. It should read 3.3K ohms. If its open check the other male connector and see if the values shows if it does you have your plug sex backward and need to be traded. If open on both test check the wiring for breaks or toggle the fooler switch the other direction. Now for the IAT Fooler Now with the female plug which is the plug that hooks to the ECM we want to measure the ohms at this plug with the fooler in the ON position. It should read 39K ohms on 6 cylinder and 56K ohm on 3 cylinder. If its open check the other male connector and see if the values shows if it does you have your plug sex backward and need to be traded. If open on both test check the wiring for breaks or toggle the fooler switch the other direction. Now lets test the normal mode. This is the normal pass through mode without the foolers... Now here in the normal mode both IAT and ECT fooler should operate the same with 0 Ohms between RED and BLUE arrows. Now you might see a OPEN at this point but trade pins on one plug and see if you get 0 ohm... There should be a pair of 0 ohm wires coming and going probing from the ECM to the sensor plugs. If this remains OPEN double check your fooler switch and make sure its in the OFF positon. Now if it continues to be a open there is a open wire somewhere. Now for error codes with High Idle Mod in place. (IAT Fooler) P0112 means you most likely got a short to ground double check your wiring for cuts, shorts, etc. P0113 means you got a OPEN wire in the fooler go back and test the bypass mode for problems. In any case remove the IAT fooler reset the code and take for a short test drive if the code returns the sensor is at fault. (ECT Fooler) P0117 means you most likely got a short to ground double check your wiring for cuts, shorts, etc. P0118 means you got a OPEN wire in the fooler go back and test the bypass mode for problems. In any case remove the ECT fooler reset the code and take for a short test drive if the code returns the sensor is at fault.

Built the high idle bomb box and when ever I hook the box up truck goes into 3 cyc high idle and temp gauge doesn't work I know the wires coming into the cab work like normal when I twiste them together so it the box that's wrong I'll get a picture up soon of it I used 1/8 watt 3.3 , 39 and 56 bought everything prowled had pictured in his CF thread. Any help thanks guys --- Update to the previous post... http://i926.photobucket.com/albums/ad109/Beanerwolfe55/image.jpg

I have been looking around at all the million ways you can do this and I came up with another way that seems pretty spiffy. Here's what I have come up with. First off, in the cab you need 3 single pole single throw switches, which are the simplest form of a switch you can get. Here is a pic of one. You install all of those, and hook one side of each switch to a good ground inside the cab. Now run the other side of each switch all outside into the engine bay. One switch will fool the coolant, one switch will turn on high idle, and one will turn on 3 cyl idle. The positive side of each relay is "always on" positive, so you can jumper from one relay to the next. The negative is the switched part. Now you need 3 relays. The ones I found are as common as pocket lint so are $2 a piece. These are the ones you need. http://www.parts-express.com/pe/showdetl.cfm?partnumber=330-073&source=googleps Any auto parts store should have them. Alright so the contacts on the relays look like this. Labeled exactly the same. To make the ECT fooler, this is how it is wired. To do the high idle and 3 cyl relays you do it like this. You might think it goes through the IAT sensor and the 56k resistor when you turn it to 3cyl idle, well it does, but as far as I can tell, 56k or more will do the same thing. So the 56k and the IAT sensor resistance will add up, but produce the same effect. This way you should only have 3 wires leaving the cab since you should be jumping ground from a place inside the cab. You put the relays somewhere outside the cab like next to the ECM. So the operation is like this. You hit the ECT switch and now it thinks it is 123F. If you hit the high idle switch it fools IAT into thinking its 28F. If you hit the 3cyl switch it fools it into thinking it is 13F or below since it adds IAT sensor into the equation on that switch. the IAT foolers must only be on separately. If you turn them both on, it will add up all the resistors and do 3cyl. This means there is no IAT fooler switch or high idle mode switch. There is only a switch for high idle that you turn on or off, and a switch for 3cyl which you turn on or off. The relays are wired so that the normally closed position is the stock position, so if the relays mess up, it will be just like stock. It is also good because they don't need any power to be remain closed. Only when they energize do they switch to the resistors. The only long wires you should have are the 3 from the switches and the 1 positive wire. You jumper the positive to the other 2 relays. If you mount the relays by the ECM anyways, that will make a short trip to it and you can even splice into the ECT/IAT wires as they go into the ECM. Operation Cold Engine Start (Coolant <140°F - Outside Temp > 32*F) Turn on the high idle switch. Now start your engine. With in about 2 minutes the high idle should start. Once the high idle starts turn off the high idle switch and allow the ECM to monitor the IAT temperatures. As the engine warms up to 170°F it will cancel on its own and idle normally from that point on. Cold Engine Start (Coolant <140°F - Outside Temp < 32*F) Turn on the 3 cyl switch. Now start your engine. With in about 2 minutes the high idle should start once it get to 1,200 PRM's the 3 cylinder mode with begin. Once the high idle starts turn off the 3 cyl switch and allow the ECM to monitor the IAT temperatures. As the engine warms up to 170°F it will cancel on its own and idle normally from that point on. Warm Engine Start (Coolant 140°F-170°F) You can start the high software with a warm engine. At this point you need to use both the ECT switch and high idle or 3cyl switch. Select the proper idle switch for your weather conditions as in cold start procedure. Once the high idle starts turn off the foolers and allow the ECM to monitor both ECT & IAT temperatures. As the engine warms up to 170°F it will cancel on its own and idle normally from that point on. Forced High Idle Turn on both the ECT fooler and the high idle switch. Start the engine and allow the high idle to start. Once the high idle starts turn off the high idle switch but leave the ECT fooler on. This will allow a forced high idle that never ends. To cancel it just turn off the ECT fooler and it will cancel. So what do you guys think? I can't test out my idea until I decide to get a 24V

I had someone ask me to make a simplified version of Mike's high idle switches schematic. I know they can be a little confusing for those who don't do much electrical so I tried to make it as easy as possible. This first picture shows how the switch works. It is very important to understand this first, by understanding it, you will know how all the rest has to work. All of the drawings of the switches are always in the same direction, so they all directly relate to the top of the picture. This switch works by having 2 central contacts that close with the top or bottom contact. Sorry about drawing it on paper, I know it's kinda cheap but paint wasn't giving me enough room Here is his writeup to see the exact switches and everything he used, and more info. http://mopar.mopar1973man.com/cummins/2ndgen24v/high-idle/high-idle.htm This is the switch and ECT (Engine Coolant Temperature) fooler wiring. This is for the other 2 switches that run the high idle and 3 cyl idle.

Take a look... It works excellent and is a great way to warm up your truck on cold winter mornings. It will warm up a truck in under 10 minutes! :thumbsup http://mopar.mopar1973man.com/cummins/2ndgen24v/high-idle/high-idle.htm