Limp Home/Flickering SES and an upcomming engine swap - Third Generation F-Body Message Boards

grosss · 01-11-2008, 10:10 PM

Hey I know I'm talking about a truck here and not a 3rd gen, but you guys seem to know your stuff so I'm hoping you'll give me a hand!

I have a 1993 Chev Silverado, 1500 with a 4L60e. PCM is 16168625, and the software on the original chip is BDFK with an e6 mask.

A little backround info on the truck:
-picked it up for free, been working on it for over a year to fix it up
-459,000kms on it, 5.0L V8 TBI, everything original, runs strong

I'm a student and have been trying to spend as little money as possible on this truck ever since the mechanic ripped me off when performing the safety inspection, so keep cost in mind with your suggestions please

.

I have been given a perfectly running 5.7L TBI engine out of a 91 van, and plan to do the swap over the summer. In preparation for this I've been looking into reprogramming the ECU. The original chip is a 27C512, and I have a programmer and a spare 27C512 that I've been writing to. I managed to safely remove the original chip and put in a D2 28 pin DIP socket.

Now i broke two pins on the original chip and had to solder in some copper wire to patch it for now, so I want to use the new chip I have. Whenever I swap in the new chip, the truck goes into Limp-Home mode, and the SES light flickers like crazy. but when I put the original chip in the SES light stays solid, and if I unplug the PCM box for a few seconds, sometimes the light goes away and the truck gets out of limp home mode (recent attempts have failed however).

I've narrowed it down to a programming error with either the checksum or the byte size settings.. is there something I can change in the programming of the chip to make it ignore the errors and get out of limp home? I have a feeling the definition file I downloaded isn't quite set up right, but I can't find a good DIY walk through for setting up the tunerpro settings and the settings when writing to the chip.

Also, does anyone have any tips on what parameters in the e6 I can change to get a little more low end power, and some better fuel economy on the highway? I'm not going to put any money into the physical engine since it's going out in a few months, but any tweaks I can do via the chip for now would be nice

.

And (I know this post is getting long, this way I only have to post once) Has anyone done a swap like mine before? How much of the software would I have to change for the new engine, and can I keep this PCM?

Thanks for any and all help, and if anyone wants/needs I can post the BDFK bin up (I've never seen it anywhere on the internet).

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Fast355 · 01-11-2008, 11:07 PM

Quote:

Originally Posted by grosss

Hey I know I'm talking about a truck here and not a 3rd gen, but you guys seem to know your stuff so I'm hoping you'll give me a hand!

I have a 1993 Chev Silverado, 1500 with a 4L60e. PCM is 16168625, and the software on the original chip is BDFK with an e6 mask.

A little backround info on the truck:
-picked it up for free, been working on it for over a year to fix it up
-459,000kms on it, 5.0L V8 TBI, everything original, runs strong

I'm a student and have been trying to spend as little money as possible on this truck ever since the mechanic ripped me off when performing the safety inspection, so keep cost in mind with your suggestions please

.

I have been given a perfectly running 5.7L TBI engine out of a 91 van, and plan to do the swap over the summer. In preparation for this I've been looking into reprogramming the ECU. The original chip is a 27C512, and I have a programmer and a spare 27C512 that I've been writing to. I managed to safely remove the original chip and put in a D2 28 pin DIP socket.

Now i broke two pins on the original chip and had to solder in some copper wire to patch it for now, so I want to use the new chip I have. Whenever I swap in the new chip, the truck goes into Limp-Home mode, and the SES light flickers like crazy. but when I put the original chip in the SES light stays solid, and if I unplug the PCM box for a few seconds, sometimes the light goes away and the truck gets out of limp home mode (recent attempts have failed however).

I've narrowed it down to a programming error with either the checksum or the byte size settings.. is there something I can change in the programming of the chip to make it ignore the errors and get out of limp home? I have a feeling the definition file I downloaded isn't quite set up right, but I can't find a good DIY walk through for setting up the tunerpro settings and the settings when writing to the chip.

Also, does anyone have any tips on what parameters in the e6 I can change to get a little more low end power, and some better fuel economy on the highway? I'm not going to put any money into the physical engine since it's going out in a few months, but any tweaks I can do via the chip for now would be nice

.

And (I know this post is getting long, this way I only have to post once) Has anyone done a swap like mine before? How much of the software would I have to change for the new engine, and can I keep this PCM?

Thanks for any and all help, and if anyone wants/needs I can post the BDFK bin up (I've never seen it anywhere on the internet).

Ditch the $E6 bin and go to the $0D bin BHMC for your stock 305.

I have run the following engines/trans combos on this PCM

305/4L60E
350/700r4
454/4L60E
2.8/4L60E

grosss · 01-12-2008, 12:27 AM

I've been looking into switching to the OD, what do I have to do exactly to make the swap?

Update: I've realized that the DIP socket I put in the board to make putting the chip in easier (like the D2 DIP socket from Moates) is causing a lot of signal loss, I took it out and just shoved my new chip in straight to the memcal board, and it worked (with a direct copy from old chip to new in the programmer).

If I write ANYTHING but the original code on the chip, I get the SES light (though now not flickering) I took my original code and just changed a few minor items and it still didn't take (stuck in limp-home mode). What am I doing wrong??

RFmaster · 01-12-2008, 02:15 PM

did tuner pro recalculated check sum?

grosss · 01-12-2008, 04:18 PM

Well, that's what I'm wondering about, I have a feeling it's a checksum problem. in the XDF definition it says the checksum value is stored at 4006, and start value is 4008... on my original code the value at 4006 is BC, and after changing some stuff around in the code, that value is changed to 9D, so I'm assuming tunerpro is recalculating it properly, but I have no idea how to check if it's right, or if those start and end values are correct.

Fast355 · 01-12-2008, 05:52 PM

Quote:

Originally Posted by grosss

I've been looking into switching to the OD, what do I have to do exactly to make the swap?

Absolutely nothing other than burning the calibration into the chip. I tried to work with $E6 on a 1993 Astro CPI motor and abondoned it for $OD for the same reasons you state, I believe the Check Digit is not defined correctly in either the hack or the .XDF you are using.

grosss · 01-15-2008, 05:28 PM

Alright, so after playing around, getting fed up, and making a home-made adapter (Like Moates G1 adapter) I figured out that the problem was most definitely caused by the $E6 definition... only my original software on either of my chips would work right. After switching to the $0D even with some modifications to the code in TunerPro she started right up with no SES light!! Thanks alot Fast355!