6.1 Swap Won't Rev Past 3K HELLLLPPPPP!!!

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You gotta tell us all the info. So you got a different pcm, 5.7 hemi standard trans, and the guys over on DSP told ya that the predator you had was wrong and you needed the u7137, and have you updated the predator as they said? Just a thought, but have you changed the knock sensor? I'm no guru, but thought I would ask. Let us know if the new download helped from Diablo.
 
I might be selling my entire set up, 03 computers, wiring harness, 5.7 car intake manifold, manifold spacers, 5.7 injectors, hypertec power programmer, and car and truck fuel rails. I didn't post this in the for sale section cause I'm not to sure if the 3g stuff should go there. This set up will get you driving and is great condition, I'm going another route, so if interested send me a pm. I will tell ya thru pm waht I'm asking for all of it.
 
I wonder.... you are using the 5 speed manual ecm. How are you handling the clutch start bypass? My assumption is it is grounded across to allow start up. Is this correct? If it is doesn't this give the ecm the believe that the clutch is disengaged at all times? If the ecm thinks the clutch is depressed is it possible that the neutral rev limited is set at/near 3000 rpm?
~Michael
 
Ok so here is an update. Dad took the car to a CMR dealer today who is VERY familiar with tuning the hemi motors. We have used him in the past for tuning and he knows these ecm's. He spent about three hours working with the software. He updated the diablosport to the lastest version to start with. Next, he disabled the downstream oxygen sensors. He then tried everything known to man to remove the "rev limiter" with no success. He then informed my dad that the ecm which was purchased from S&P as a plug and play part was not what we were told it was. The mapping on it was for a 5.7 hemi and not a 6.1 as we were told. We were told that it was setup for a 6.1. Here we go again!!!! Not only has my dad been ripped off by Ben at Plum Floored, now S&P!! Dad attempted to contact the guys at S&P this afternoon but the tech guys had already left for the day lol. Surprise! As far as the clutch input goes, I wish I had a wiring diagram for this harness. We are almost ready to rip this bullshit out and put a carb on it. How can these guys get away with this ****!
 
Man I feel for you. Did you buy the PCM direct from S&P? I'm sure they will make it right if you did. If it went through Ben, I'm sure he used your PCM on another project gave you junk and the invoice for the correct PCM. That's his style. Bait and switch. I have seen it with my own eyes. Although it was a few years ago, but things never change for a crook.

Edit, why not look at a megasquirt instead of tossing a carb on it. It would ne cheaper than buying all the other stuff.
 
Talk to Mark at S&P, he owns the joint, and I'm sure he will make it right. He has done right by me, tech and products.
 
Little update here. The ecm purchased from s&p was returned and money was refunded. We sent the other 05 ram ecm to hotwire. They disabled the auto trans, emissions functions, and installed a 6.1 tune with some tweaks to go along with the headers and air intake. Now we have an ecm that we know is right! Yay! Next step is to address the 3600 rpm rev limit, or "limp mode". After talking with the guy at hotwire, sorry I am bad with names lol we figured out something interesting. After closer inspection, one of the troubles codes stood out. The oil pressure code. Well, it seems that the 05 hemi trucks had an oil sending unit for the gauge, as well as one for the ecm. The harness that we havehas no connectors for the oil pressure sensor for the ecm. We have located the correct pin needed to install in the connector at the ecm, and the pig tail and sensor to install in the motor. Tomorrow night I am going to install these parts and keep my fingers crossed lol. Everything points to this being the issue. I will update the thread with the results. Thanks for everyones input.
 
Just asking here, but by chance was it cut off during the install cause someone thought, "oil pressure sender, why is this plug on here" and cut the wires?? Stranger things have happened.
 
Definetly not. This wasn't a hack job install. It simply wasn't wired in to the harness.
 
I didn't mean "a hack job" install. Just asking!! I've cut wires by accident, thought the same may have happened here. So is Hotwire making a new harness?
 
No offense taken. Im going to just add the wire to the harness and connect it at the ecm. Hardest part is going to be getting the connector apart! These damn things are tough lol.
 
BadAss71 said:
After talking with the guy at hotwire, sorry I am bad with names lol we figured out something interesting. After closer inspection, one of the troubles codes stood out. The oil pressure code. Well, it seems that the 05 hemi trucks had an oil sending unit for the gauge, as well as one for the ecm.
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Seems a little odd to me that without an oil pressure signal to the ecm it would even start. I guess running under 3600 rpm with no oil pressure is okay in a Hemi!! I wonder if that will cure your extended crank time as well?
Good luck and keep us posted.
~Michael
 
Is Hotwire gonna do something for ya since they forgot to put the oil presseure plug in the harness? Maybe a free tune? I'll be double checking mine when it arrives just to be certain.
 
I had the same feeling dartman, and wouldn't you know, it didn't fix a thing. I connected the scanner and checked for codes again, since this was a totally different ecm now and there was a code thwt wasn't there before. I know this for sure because I wrote down all of the codes when talking to hotwire. Now we had a code for the ckp sensor, or "crank sensor". This was never there and why I dont know. What I found was that when the guy put the pins in to the crank sensor connector he had swapped the 5 volt reference wire with the signal wire. Unreal. I figured well ****, this should fix the problem right here. Well it did, kinda. With the pins now in their proper location, it fires right up with just a touch of the key! Amazing! Lol. I took the car out for a spin and right away found out that the rev limit issue is still there. From doing a **** ton of research it appears that the ecm is looking for a speed reference, and without one the ecm wont allow it to rev over 3600 rpm. I guess this feature keeps kids from neutral dropping at 6 grand. I have found a couple of different speed reference generators on the web but without making some phone calls I dont know if these have the correct threads to attach it to the speedo bullet on the trans. And also being able to connect the speedo cable to it as well. So, thats the update! Still fighting this damn thing. Has anyone else with this same combo had this issue? The harness we have was purchased from Plum Floored and not hotwire unfortunately. If it was it would probably work!
 
This sounds like a bad nightmare. I purchased ky harness from HOTWIRE I haven't installed it yet but I'm pretty close. Hope you get things sorted out without dumping a bunch more money into it. Good luck and definately keep up posted and don't let it get you down.

Aj.
 
I purchased my harness from Hotwire, and the motor started on the first crank. I even had the cam sensor unplugged so it WOULDEN't start, I wanted to crank it to get the oil pressure up, but it fired anyway. Luckily the op shot right up. Hotwire makes good stuff.
 
Just an idea, but do you have any vehicle speed sensor input to the ecm? Since it's a 727 it wouldn't have a VSS on it.
If you had it in a man trans car & revved it would it have a preset rev limiter to protect against a missed shift? It would need to see the vehicle speed if it does to know the vehicle was moving & then not engage the rev limiter. It may be looking for that VSS signal.
Just a thought.
 
Lonewolf3165 said:
Just an idea, but do you have any vehicle speed sensor input to the ecm? Since it's a 727 it wouldn't have a VSS on it.
If you had it in a man trans car & revved it would it have a preset rev limiter to protect against a missed shift? It would need to see the vehicle speed if it does to know the vehicle was moving & then not engage the rev limiter. It may be looking for that VSS signal.
Just a thought.
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Sorry, Just read your last post. I see you may be on to this track already. Good luck. :eek:ops:
 
So for certain the pcm is programmed for a manual trans??
 
The harness we have was purchased from Plum Floored and not hotwire unfortunately. If it was it would probably work!
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I have been hoping for you guys to get this problem figured out before the MATS. Any chance you can return the harness to Plum Floored and buy one from Hotwire ? I've heard that PF can be accommodating if nudged just right....:poke:
 
I also have an '05 Ram manual trans PCM. The PCM gets a Vehicle Speed signal from the ABS controller. The signal is hardwired (not on the bus) so duplicating it should not be too difficult. We just need to know what type of signal the PCM is looking for. I bought a signal generator from Dakota Digital http://www.dakotadigital.com/index.cfm/page/ptype=product/product_id=126/category_id=287/home_id=59/mode=prod/prd126.htm and plan to use it to send a VSS to the PCM but I am not at that stage yet with my build so I can't be of more help, sorry. Hopefully in the next few weeks I might be able to experiment with this a little.
 
hey bad *** 71 i need to talk to you about this conversion. i doing a similar project with a 71 duster using a 08 5.7 hemi with a NAG1. i trying to see what my option are with the power steering
 
eric202006 said:
hey bad *** 71 i need to talk to you about this conversion. i doing a similar project with a 71 duster using a 08 5.7 hemi with a NAG1. i trying to see what my option are with the power steering
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Do plenty of research before you commit full bore to using the NAG1 (car transmission) in your Duster. I found out that the NAG1 is a nightmare to get working in an old car. It gets its speed readings from sensors in the anti lock brakes at the 4 corners of the car. Then the computer figures out when to tell the transmission to shift,etc. I won't say you can't make it work, and if you do :prayer:...lol ! I'm putting an 06 model 5.7 Hemi in a 70 Duster, and was going to do exactly as you have planned. The 5.7/NAG1 I bought came out of a smushed 2006 Wagnum R/T that had 6000 miles on it. I would have liked to have been able to use that tranny since it was so low of miles. I sold it and bought a 545RFE out of an 07 Hemi Durango 2wd. I need to get a truck computer, because the car computer won't run the truck transmission I have. Have fun with your build.
 
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