ECM/Programming differences

01-04
Chevy S10 Pickup / GMC Sonoma 4.3



01-07
Chevy Silverado / GMC Sierra 4.3



01-04
Chevy Blazer 4.3



01-05
Chevy Astro / GMC Safari 4.3



01-07
Chevy Express / GMC Savana 4.3
 
 
According to the HP Tuners website, this is some of what their tuner supports for the GM Truck V6s....
 
What kind of programming/software differences are there on the vehicles? Is the ECM the same part number for all of those?
I fired off an email asking about the '05 Blazer 4.3, and they say it's different from the '04 but they don't say how...
 
Can anyone list off any possible differences in 'em?
As much as I like my PP3... I wouldn't mind having some onboard readings and such, as well as the ability to get rid of that evil RPM holder, lol...
 
If there is a major software difference... Could I theoretically drop in an ECM from one of the supported years and have it work without issues, or am I out of luck on this one?

To my understanding there really shouldn't be a difference between the 04 and the 05 truck as the 05's were supposed to be the runnoff of the 04's I can't see Chevy making changes for a truck that stops production before mid year. . I have always ordered anything for mine as long as it says 03 or 04 never had problems yet. Maybe a could be the lucky one!!   HAHAHAHAHAHAHAHAHAHAHAHAHAHAHA    Yeah Right!!!

Well, I know the hypertech PP3 for the '05 only works on the '04 - '05 year... According to the site and my sticker on the programmer...
 
Hopefully it's all the same... but that's a fair sized piece of money if it doesn't work, lol

DrPerry,
 
Besides a 'Quiet Cam' this is the only difference I know of for '04-05' & latter '03'engines below.    Also, if you are looking for a programmer for realtime data, I have my brand new Jet Programmer for sale for my '05' 5-speed. It really woke up my truck.  The only reason I am selling it is because I lost my job and need the $$.  $280 shipped and its yours.
 
POWERTRAIN CONTROL MODULE AND SOFTWARE WITH ADDITIONAL MONITORING FUNCTIONS
A new Powertrain Control Module (PCM), called P59, manages the 4.3L LU3. This PCM increases clock speed from 21 to 24 MhZ and doubles memory (1.1 megabyte) compared to its predecessor. It also provides one of the most sophisticated engine control systems in the industry. The P59 is common to the LU3 and all gasoline-powered Vortec V8 truck engines.
Commonality offers the advantage of reducing inventory complexity and increasing efficiency at various assembly plants. More important, the P59 offers the most precise engine management possible, optimizing performance according to temperature or operating conditions and virtually eliminating unintended variation in every function it controls, from ignition timing to fuel delivery to transmission shift points. It also allows GM Powertrain engineers to monitor more engine operations and improves the accuracy and robustness of the OBDII (for On-Board Diagnostics) system.
For example, the PCM now measures electrical current flowing to the oxygen (O2) sensors on vehicles equipped with the 4.3L LU3 (crucial components of the emissions-control system). Previously, the O2 sensors were monitored with a time-to-activity algorithm, which required more measurement latitude to ensure proper operation. The new PCM immediately reports a malfunction in an O2 sensor with virtually no margin for misreporting. It also allows a new Engine Off Natural Vacuum diagnostic (EONV) for the On Road Vapor Recovery system (ORVR), which reduces evaporative emissions by preventing gasoline vapor from escaping the vehicle into the atmosphere. With EONV, the PCM actually continues to operate when the engine is turned off, monitoring pressure in the fuel tank and ORVR system. If pressure bleeds off more quickly than ambient temperature and other conditions indicate, the PCM can determine whether the system has a leak, even when the vehicle is parked. The new PCM ensures that the LU3 operates according government emissions regulations. And thanks to its precision, it will also reduce the number of false alarms-- OBDII ``service engine’’ warning lights--that require dealer intervention.
 
I also heard from a GM factory engineer, that in late '04' they used some common parts off of Sierra/Silverado production line to fullfill the number of remaining Blazer bodys they had.  This might mean that we '05' Blazer owners may have Sierra/Silverado ecms.  

^^ That is the information from my references.  Since '96 (possibly earlier), the ECM has been shared between the S-series and the C/K series vehicles.  It makes sense that when the trucks changed in '04, that the S-series would follow suit once supplies of the out-going ECM dwindled.  

quote:

ORIGINAL: BlazerSS

DrPerry,

Besides a 'Quiet Cam' this is the only difference I know of for '04-05' & latter '03'engines below.    Also, if you are looking for a programmer for realtime data, I have my brand new Jet Programmer for sale for my '05' 5-speed. It really woke up my truck.  The only reason I am selling it is because I lost my job and need the $$.  $280 shipped and its yours.  

 
Isn't that about the same as the Hypertech PP3? I tried reading up on what it can do, but the Jet site isn't working for me at the moment...
 
Aside from adjusting tire size, and maybe a small boost in power, I mainly just wanna get rid of the RPM holding feature, lol... But the real time diagnostics will come in very handy with my rough idle finding...
 
 
 
 
 
I know when my Hypertech fires up it says "2005 GM Truck/SUV" and lists the engine size and VIN #...
 
So from what I've seen, anything that works for the '04 year, or '05 year of 4.3 trucks should work with mine...

The Jet allows you to increase the 'RPM Holding Feature' / Rev Limiter by 800rpms, remove the top speed governor, etc.  I have heard good things about HP Tuners and Diablo knowing what the heck they are doing with the tuning of their programmers as well.  However if it were me, I wouldnt risk the fact that if its not programmed for the '05' it might not be able to read it and be stuck with a tuner I cant return.  If you have the benjis to do it, then go for it.   Good luck!

The RPM Holding feature that I'm talking about is NOT the rev limiter... My hypertech can change that too, lol (dropped down to 5200 or so right now)
 
I'm talking about GM's "safety feature" that when you pull it out of gear when you're going down the road, to shift from 3rd to 4th without the clutch, for example, the RPM's drop WAY to slow, because GM has it set to keep the RPM up above idle, in case you accidentally popped it out of gear... The automatics do the same thing, heck, even my old '93 Lumina Z34 did it. Something about less stress on the transmission or something... I think it's a hold over from the auto programming, but I'm not sure...
 
The RPM takes entirely too long to drop to make it worth shifting without the clutch, as you have too much of a speed drop...

Oh, sorry Doc.  My misunderstanding.  I hear you on the shifting in these trucks.  The one thing I really want to do is get a new shifter.  The throws are way too long in this thing.   I can't tell you how many times I buzzed 2nd by either being lazy on the cell or punching it and getting anxious.  I would get the Hurst put in, but the dealership said if I do that I will void my whole factory warranty which I have 1yr remaining on.  Oh well, good luck in your quest.  P.S. I like your Westin Brushguard setup.  I would like to duplicate it once I get money down the road.  How is it holding up to corrosion?

I've only had the Blazer since January... and the guard got put on a couple months afterwards, so it hasn't had any time to rust or anything, lol.
 
Yeah, just for fun, I pulled it out of gear going up a hill and my RPM's went up, lol.
 
Anybody know where I can score a Tech II for cheap? lmao

Dr 
 
With the Jet Programmer "The following vehicle parameters can be monitored with the scan tool function:

-Calculated Load Value
-Engine Coolant Temperature
-Short Term Fuel Trim 1 & 2
-Long Term Fuel Trim 1 & 2
-Manifold Pressure (MAP)
-Engine RPM
-Vehicle Speed
-Spark Advance
-Inlet Air Temperature
-Throttle Position
-02 Sensors Bank 1 & 2
-Mass Air Flow Value
-Live data monitoring is included on software versions 3.5-up"
 
 

I forgot to add that it also Reads and clears factory diagnostic trouble codes (turn off check engine light),
Correct speedometer and turn off ABS light after making gear ratio or tire size changes
Bypass computer aided gear selector in manual transmissions
Tri-Power performance tuning modes for regular, midgrade or premium fuels
 
Peace

Well, if I didn't have my Hypertech already, it'd definitely be worth it, lol.

I am waking this thread up again because I have a question.  I currently have the Hypertech Programmer designed for the 96-97 Blazer. It is able to clear codes, but it doesn't tell me which codes are coming up.  It looks like the Jet Programmer is a better product.  Has anybody here had the opportunity to test the two side by side?

That's strange. My Hypertech PPIII both reads the codes and gives you the opportunity to clear them.

whats really the advantage to raising the rev limiter? isnt it their to save your engine.....I've only redlined mine maybe 3 or 4 times since I owned it.......

quote:

ORIGINAL: rriddle3

That's strange. My Hypertech PPIII both reads the codes and gives you the opportunity to clear them.

 
He's running a 96 - 97... It might be an OBD 1.5 quirk...
 
 
 
 
 

quote:

ORIGINAL: blazinloud

whats really the advantage to raising the rev limiter? isnt it their to save your engine.....I've only redlined mine maybe 3 or 4 times since I owned it.......

 
It's really only useful if you've done mods to give your truck more power in the higher RPM's...
 
The 4.3 kinda falls on its face at over 5000RPM anyway, that's why I dropped the limiter to 5200, lol.

'95 was the only year for the mongrel PCM commonly referred to as OBD1.5.  But there are other challenges with the '96-'97 PCMs that make them different than the '98+.

quote:

ORIGINAL: swartlkk

'95 was the only year for the mongrel PCM commonly referred to as OBD1.5.  But there are other challenges with the '96-'97 PCMs that make them different than the '98+.

What specific challenges? 

Also, seeing as the engine and tranny appear to be the same as the 98+ trucks, then does this mean I could find an advantage in upgrading the PCM altogether to a newer version?

They may not be compatible as your vehicle has 4 O2 sensors and the '98+ have 3.  I am not sure what would be involved in the swap over, but I don't think it would be as simple as unpluging connectors and removing one O2 sensor.  You would need to look at wiring diagrams for both the 96-97 PCM and the 98+ PCM to make sure that the wires that mattered were going to be in the appropriate locations as well as remove anything unused.  But this may also create complications with the BCM (body control module) as more things moved over to serial bus communication in '98.

The challenges are in the programming end of things.  The '95 was a mess with it's mix of OBD1 and OBD2.  There are some of these issues that carried over into the 96-97 PCMs and it relates to the pre-cat O2 sensor and the programming to support it.  While the drivetrains remain relatively unchaged between the early 2nd gens and the later 2nd gens, the programming is different.

the 4l60E tranny was taken out after 03 or 04 i believe

I doubt that... It's still in the trucks... At the very least 4.3 powered 1/2 tons still have it, if not the smaller V8s... I'd imagine that the bigger V8's get the 4L80E.
 
Though, I don't have either one.
 
What did it get replaced with? GM wouldn't likely spend the money to drop an all new transmission into a vehicle they're discontinuing..

My Rainier has the 4L60E!  The Trailblazer SS got the 4L65E.  The Trailblazer 4.2L & 5.3L still use the 4L60E even now.  Only the LS-based 6.0L TBSS got the 4L65E...

I don't think the 4L60E will ever die... It's GM's most common transmission... It bolts up to pretty much any motor they have

quote:

ORIGINAL: drperry
It's really only useful if you've done mods to give your truck more power in the higher RPM's...

The 4.3 kinda falls on its face at over 5000RPM anyway, that's why I dropped the limiter to 5200, lol.

does it take into account what mods you have made?? i've been reading on this and cant figure out if it just raises the limiters.

i have a Cobb Accessport,  an Engine Management System, for my Subaru. you connect it through the diagnostic access point and the Cobb Accessport downloads its software into the ECU (electronic computer unit). from there you can add mods and use maps in the Accessport designed for each mod.

just wondering if there is anything out there for a blazer that is similer. in case i want to start modding the GFs Blazer