Nelson Tune...

VMax2007 · February 2, 2008

I received my tuned ECM/TCM from Nelson today. I am hoping to get it put in tomorrow afternoon. I am new to this and have never done this before so I am looking for pointers and have a few questions also. Please post any pointers, ideas, things to watch out for or be careful of, etc.

Here are my questions:

1. The paperwork said the ECM is locked, but it is my understanding that the E38 ECM is not lockable. Is this true or is my ECM locked?

2. I have heard conflicting opinions regarding Crank Relearns. Nelson told me only about 1 in 20 need it done and if it needs one it will throw a SES code. But reading several threads in multiple forums, I have heard you should do a Crank Relearn ANYTIME you put in a new ECM regardless of whether or not you get a SES code. Could someone please confirm and explain.

3. What is the "Pass-Key" relearn procedure? I have not installed them yet and do not know if I will need this or not, but would like to be prepared.

4. Any pointers for the Idle relearn? The directions were a little confusing.

Thanks alot for any info you can provide me. As you can see, I am just a little bit nervous about swapping computers in my $40K truck.

7LitreC5 · February 2, 2008

I'd sure like to know the answer to your #1 question.

I have only installed one tuned PCM (on a 03 Silverado) and it did need the crank relearn. It is an easy procedure. I used EFILive to do mine.

Do you know if Nelson tweaks the VVT tables to gain power?

I received my tuned ECM/TCM from Nelson today. I am hoping to get it put in tomorrow afternoon. I am new to this and have never done this before so I am looking for pointers and have a few questions also. Please post any pointers, ideas, things to watch out for or be careful of, etc.

Here are my questions:

1. The paperwork said the ECM is locked, but it is my understanding that the E38 ECM is not lockable. Is this true or is my ECM locked?

2. I have heard conflicting opinions regarding Crank Relearns. Nelson told me only about 1 in 20 need it done and if it needs one it will throw a SES code. But reading several threads in multiple forums, I have heard you should do a Crank Relearn ANYTIME you put in a new ECM regardless of whether or not you get a SES code. Could someone please confirm and explain.

3. What is the "Pass-Key" relearn procedure? I have not installed them yet and do not know if I will need this or not, but would like to be prepared.

4. Any pointers for the Idle relearn? The directions were a little confusing.

Thanks alot for any info you can provide me. As you can see, I am just a little bit nervous about swapping computers in my $40K truck.

ridnlow · February 2, 2008

Jeff, hope this helps.. Answered your questions in bold NOW GET THAT THING INSTALLED!

I received my tuned ECM/TCM from Nelson today. I am hoping to get it put in tomorrow afternoon. I am new to this and have never done this before so I am looking for pointers and have a few questions also. Please post any pointers, ideas, things to watch out for or be careful of, etc.

Here are my questions:

1. The paperwork said the ECM is locked, but it is my understanding that the E38 ECM is not lockable. Is this true or is my ECM locked? Its probably just his standard letter he sends out, as the other pcms he does lock..

2. I have heard conflicting opinions regarding Crank Relearns. Nelson told me only about 1 in 20 need it done and if it needs one it will throw a SES code. But reading several threads in multiple forums, I have heard you should do a Crank Relearn ANYTIME you put in a new ECM regardless of whether or not you get a SES code. Could someone please confirm and explain. The only time I did a Crank Re-Learn is when I got Hp Tuners myself.. I went 4 years with a Nelson Tune without doing it.. You will be fine..

3. What is the "Pass-Key" relearn procedure? I have not installed them yet and do not know if I will need this or not, but would like to be prepared.Pass Key is of course the security system that GM Uses.. If you put your PCM in and go to fire up your truck and it will only run for a few seconds then this needs to be done.. Allen has the details to this procedure on his website..

4. Any pointers for the Idle relearn? The directions were a little confusing.

Not real sure on the Idle Relearn.. If its anything you may just need to hold your truck at about 2k RPM for 15 or so seconds..

Thanks alot for any info you can provide me. As you can see, I am just a little bit nervous about swapping computers in my $40K truck.

VMax2007 · February 2, 2008

Thanks Drew!!

Yeah, regarding my question #1, that is what I figured too.

Bostonsfavson · February 2, 2008

I have two PCMs (or ECMs if you prefer) for my truck: a tuned one, and a stock one which I put in when the tuned one is busy getting tweaked. The stock PCM always throws an SES light when I put it in, and having the code read indicates that I need to have a crank relearn procedure done. I had the crank relearn done the first time I had the new PCM put in and programmed for my vehicle, and I thought that would be it. The service department at my dealership told me that it's necessary to have the crank relearn procedure done every time you remove and install a PCM. I asked them if this was true, then why does my other PCM (the tuned one, which I neglected to mention) not throw a code? They pretty much told me I was lying and that it did require the relearn procedure, so I proceeded to actually show them that it didn't. They had no explanation for this, and the issue remains unresolved. As far as I can tell, this situation may just be "one of those things" along the lines of the "one in twenty chance" that your PCM is going to need a crank relearn procedure. Butch (my Wester's tuner) told me that you do not have to do a crank relearn every time, and since when I put the tuned one I don't I'm inclined to believe him. He thinks that perhaps the techs aren't doing it correctly; for example, they may be neglecting to depress the brake pedal while performing the procedure. Hopefully you don't have to, but if you do, it shouldn't be too difficult to find a local shop with a Tech 2 scan tool that will do the relearn for a nominal fee. Be sure to let us know your impressions of the tune! I know that my Wester's Tune really woke up my truck; it actually feels as though it has 400+ HP and lb-ft. of torque.

I've never even heard of the idle relearn or any PassKey concerns, but then again my experience is limited to the L92 engine, and there are some differences there. All I know is that I've swapped out PCMs about 10 times now and the only issue I've ever encountered is with the crank relearn. Good luck!

2 fast · February 2, 2008

I received my tuned ECM/TCM from Nelson today. I am hoping to get it put in tomorrow afternoon. I am new to this and have never done this before so I am looking for pointers and have a few questions also. Please post any pointers, ideas, things to watch out for or be careful of, etc.

Here are my questions:

1. The paperwork said the ECM is locked, but it is my understanding that the E38 ECM is not lockable. Is this true or is my ECM locked?

2. I have heard conflicting opinions regarding Crank Relearns. Nelson told me only about 1 in 20 need it done and if it needs one it will throw a SES code. But reading several threads in multiple forums, I have heard you should do a Crank Relearn ANYTIME you put in a new ECM regardless of whether or not you get a SES code. Could someone please confirm and explain.

3. What is the "Pass-Key" relearn procedure? I have not installed them yet and do not know if I will need this or not, but would like to be prepared.

4. Any pointers for the Idle relearn? The directions were a little confusing.

Thanks alot for any info you can provide me. As you can see, I am just a little bit nervous about swapping computers in my $40K truck.

I'm sure Nelson found a way to lock the ecm. You can't blame them there. If they send you a tune and you fool with it, the truck blows up, they look bad. I'll bet it's locked some how.

Google crank relearn and get the procedure it doesn't hurt to do it any way and you can do it yourself. Need it or not. Gm tells you need to any time you change the ecm. Play the saftey and do it, it's no big deal.

If the truck won't start do the pass key.

For the idle relearn I hold the rpm's at differant levels with the truck in park, untill the truck idles. The ecm will learn it from there.

I've never had a box tune. I tune with a HP Tuner Pro. But i wouldn't be nervous about putting in a Nelson tune. They are by far in the top three tuners. Follow there direction and you'll be fine.

Nice Ride

svensk · February 2, 2008

Jeff, you NEED to get a relearn done. Not right away but eventually or you won't be getting full performance out of it. I went 4 months with my wait4me without a relearn and it wasn't setting an SES, but certain engine sensors weren't being read. I got the crank relearn done at Bona Bros. in Fridley and within 20 miles I felt a difference in performance. The PCM needs the relearn so it can start making adjustments to the timing tables.

ridnlow · February 3, 2008

Jeff if you can find someone to do it for cheap then I would get it done.. Not anything to be in a hurry about though.. Svensk, Exactly what sensors werent reading?? The relearn is just to so that the cam and crank sensors are lined up.. You can adjust timing just fine without having this done.. Also the PCM only makes adjustments to the timing tables when the tuner tells it too.. All it knows is that at this rpm and this airmass = this degree of timing.. If it senses knock or if there is torque management only then will it pull timing..

Jeff, you NEED to get a relearn done. Not right away but eventually or you won't be getting full performance out of it. I went 4 months with my wait4me without a relearn and it wasn't setting an SES, but certain engine sensors weren't being read. I got the crank relearn done at Bona Bros. in Fridley and within 20 miles I felt a difference in performance. The PCM needs the relearn so it can start making adjustments to the timing tables.

VMax2007 · February 3, 2008

Jeff if you can find someone to do it for cheap then I would get it done.. Not anything to be in a hurry about though..

is FREE cheap enough? I have a guy with HP Tuners doing it for me tomorrow (Monday) for free after work. He is a local guy that also posts on PT.net

ridnlow · February 3, 2008

Jeff if you can find someone to do it for cheap then I would get it done.. Not anything to be in a hurry about though..

is FREE cheap enough? I have a guy with HP Tuners doing it for me tomorrow (Monday) for free after work. He is a local guy that also posts on PT.net

Awesome! Free is fantastic as it takes maybe 30 seconds to do lol.. I feel sorry for the people that are having to pay 80 to 100 bucks to get it done.. I asked you over on PT.net but ill ask here as well.. How the heck is it running??

VMax2007 · February 3, 2008

Jeff if you can find someone to do it for cheap then I would get it done.. Not anything to be in a hurry about though..

is FREE cheap enough? I have a guy with HP Tuners doing it for me tomorrow (Monday) for free after work. He is a local guy that also posts on PT.net

Awesome! Free is fantastic as it takes maybe 30 seconds to do lol.. I feel sorry for the people that are having to pay 80 to 100 bucks to get it done.. I asked you over on PT.net but ill ask here as well.. How the heck is it running??

Check out my thread for my opinon on it.

http://www.gm-trucks.com/forums/index.php?showtopic=74118

I'm like a little kid with a new toy (that's better than most of the neighbor kid's toys )