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- Technical Discussion and Customizing your H3 (http://www.elcovaforums.com/forums/forumdisplay.php?f=26)

- - PCMforLess (http://www.elcovaforums.com/forums/showthread.php?t=23917)

I recently installed a new core PCM from PCMforLess. I really like the way my vehicle operates with it installed. The installation was rather easy. However, the instructions say I need to have a CASE relearn done using the Tech II scan tool.

I am showing no "check engine" light; therefore, I am trying to determine if I still need to have this procedure done. Per the PCMforLess instructions, it sounds like I need to do it regardless. However, if I don't need it, I would like to avoid the time, effort, and cost.

PCMforLess said

1. You are good to go to reset the oil light. Sometimes it gets reset when we
reflash them.

2 The rough idle is normal for the first 100 miles of operation. After
that it should clear up and go away. If you used a CORE exchange that you
still must get a CASE relearn done even if the light is not on.

If they reprogrammed your core you almost always don't need a case relearn because your CKP sensor data is already stored.

The best thing I found is to start the vehicle when cold and just let it ldle to normal operating temps. You can repeat this after it cools with the AC on. This will also help the RPMs drop when you let off the gas or press in the clutch.

PCMforLess does a good job.

PCMforLess has 3 choices: (1) core PCM exchange, (2) send in your PCM, (3) loaner PCM program.

I went with option (1) which means I got a new PCM module already programmed up. However, it does need a CASE relearn.

If you do option (2) or (3), you won't need a CASE relearn as they will read the calibration data from your existing PCM and apply it to the new PCM.

If I had to do it again, I would have gone with option (3) as it is so easy to install. If you can live without your H3 for a bit, option (2) is the very easiest and cheapest route as there is nothing to return back to PCMforLess.

So what did they do? Change shift points? rev limiter/ tire size?

And what's the impact on your H3 performance?

Quote:

Originally Posted by timgco

So what did they do? Change shift points? rev limiter/ tire size?

www.pcmforless.com

For me, I just told them how I drive my H3, tire size, and what I was looking for. So far I have only about 200 miles with the new PCM, but it no longer feels sluggish out the gate, it feels zippier, and the speed limiter is gone. They claim you will see improved mpg, but my ride is so new I never recorded the pre-mod mpg.

OK someone tell me what this means "CASE relearn done using the Tech II scan tool."
I want a improvement, but have no clue what I should do and for that matter do not want to get into something that I have no idea what I am doing.

is this all a easy fix, even for the novice like myself??

Quote:

Originally Posted by K9sH3

CASE is the crankshaft angle sensor. It detects engine miss. I know this only because I read it. In short, when a computer is completely rewritten with the latest GM calibration, the CASE information is lost. To relearn the information, a dealership or shop with a Tech II scan tool must perform the procedure, which took about 5 minutes for me. The only time you need a CASE relearn is when using the core program. If you go with the other options PCMforLess already has your calibration info from your current PCM.

Quote:

Originally Posted by K9sH3

is this all a easy fix, even for the novice like myself??

I would equate it to as easy as changing your oil or installing a new card and drivers in your home PC. Here is som more info with pictures.

Thank you Mountianbiker. Sounds like a good idea.

Cheers

How long after did you see the difference?

Quote:

Originally Posted by K9sH3

How long after did you see the difference?

I felt it more zippy and less sluggish from 0MPH to 30MPH. This feeling was immediate after installation. It is also zippier through out. It is claimed to aid in gas mileage, but I have never measured before or after as I only had about 1100 without it and 200 with it. Plus, I didn't buy the thing for its gas mileage (even though we'd all love to have 1000mpg -LOL). I noticed it also doesn't have the speed limiter. This is helpful here on the occasion.

On Friday I had the CASE relearn done. You will felt no change before or after this is done. It was a 5 minute job from a garage with a Tech II scan tool. You only need this if you get the core exchange. The other 2 buying options it will already be done for you; therefore, I might recommend these. The thing with the core exchange is that you only have to do the install once. With the other options it will be twice.

Install is quick and easy. I have the habit of breaking plastic tabs in the cold, cold weather. Just take your time (and do it in your warm garage). The install was about 5 minutes starting, 5 minutes of labor, then 30 minutes to do the security relearn. The latter isn't apparently always needed, but you will know it is. It is really easy also. It just has steps where you need to do this and that and wait between steps. If you have no fear in changing your own oil then you should have no problems. Some people have recommended moving the fluid reservoir for more access room. I think they are smoking wacky weed as it would make the installation longer, more complicated, and really isn't necessary.

I was looking in Performance Products catalog last night. There seems to be loads of these "tuning computers" to mess with performance. This, however, was available now for the H3, was fairly inexpensive, and I am happy with the benefits. (LOL- would be nicer I guess if GM shipped it initially with one.)