TBI conversion EPROM burning problem

AnthroCruiser · 03-03-07, 03:28 PM

Hi Everyone,

Does anyone have an EPROM image for a 2F (I have a 1977 FJ40, desmogged) for use with a Chevy 4.3 TBI conversion?

Here's the problem I'm having:

I did the conversion last summer and the cruiser runs ok with the original chip (but not great). So, I wanted to improve the performance with a properly tuned chip... so I got a blank EPROM and burner, and asked TomQ, who did the great Tech Link on the TBI conversion, for his EPROM image, which he generously supplied.

I recently had the chip burned by someone here in town and the programmer has verified that the chip matched the image, but when I put it in the Land Cruiser (we tried this twice), I just get the fast-blinking check engine light and limp home mode. So, I thought that perhaps the image had gotten corrupted in the email or something, and Tom was kind enough to email me another copy, and it burned with the same results.

So, it seems like there are two possibilities here.
1. The image is bad (which doesn't seem likely becasue Tom is using it) or
2. There's some problem with the process of burning it to the EPROM. I don't see how this could be, considering the fact that the chip verifies to the image.

If I put the original chip back in , it still runs fine, so I'm ruling out a problem with the ECM or sensors on my cruiser.

Since I can't seem to narrow it down any further (and can't figure out what the problem would be with the burning process), so I'd like to try a different image. On the other hand, if anyone has an idea why the program might verify fine but still not work in the ECM, please let me know! Any help or ideas would be appreciated

- Matt

PS - Thanks for your help Tom!

tabascoloco · 03-03-07, 08:48 PM

I had the EXACT same problem. I was told to try burning higher frequency, etc... don't know what the problem is. mine verifies as well. I tried dozens of chips, various brands, etc. Same think ...steady flashing. Don't know what the problem is. I thought that perhaps the OFFSET needs to be a set to a different value. That perhaps the DATA is verified, BUT WRITTEN TO THE WRONG STARTING ADDRESS/ENDING ADDRESS.... that's where I'm leaning to right now...I think that i read somewhere that the first so many bytes of the eprom are blank or something like that...

Let me know if you figure it out!

PS: I have what may be the say file 2f.bin and want to try and see how it compares to the one that I paid a company to make for me.

AnthroCruiser · 03-04-07, 12:25 AM

I'll certainly let you know if I figure it out.... its not looking promising at the moment though.

BTW, the file I have is named 2F_tbi.bin. Don't know whether it's the same file or not.

Hopefully someone who has done this before with some success will show up and give us a hand.

- Matt

tabascoloco · 03-04-07, 09:17 AM

I just found my file. It is exactly 4,096 bytes (or 4K). I've looked at many other GOOD .bin files and this is the correct size for the 1227747 ecm.

The CEL is supposed to flash constantly when the ECM is bad (or chip plugged in wrong or incorrect, etc).

Something is definately wrong...I think that I would have to have a spare KNOWN GOOD and WORKING set of chips and/or ECM to be certain that it is the chip and not a bad socket/ecm/connection. If you swap in a known good chip and it works, then it would have to be something with the way it burned. I have the exact problem with the 2f_bin.bin file. I've looked at it in TuneCat and it looks fine to me... I think it is the way the chip is burned. Someone suggested to me that you increase the pulses like 10 fold and it will burn better. Most agree that the 2732's are difficult and a real pain to fool with. I don't plan on doing this often...I have several 1227747 ECM's and just want to have a couple of different programs to try. I have one that I paid almost $300 for. It is custom made for the 2F. When I get the hang of this programming business, I will pull it and look at it in TunerCat. For now, I too just want to see how the 2f_bin.bin works....

AnthroCruiser · 03-04-07, 03:18 PM

My bin file is the same size. I'm going to try to copy and then burn a new chip from my original Chevy chip.... this should indicate whether the problem is with the image or with the burning process.

- Matt

tabascoloco · 03-08-07, 07:30 PM

I received word that this is very common when the file is burned with a bad checksum. I was also told that certain software checks and corrects the file prior to the burn.

I was told that this never happens if you use the following:

http://tunerpro.markmansur.com/downloadApp.htm

I have NOT verified this. I plan to give it a try this weekend.

AnthroCruiser · 03-08-07, 11:51 PM

OK, I opened my bin file in TunerPro (but didn't make any changes) and then saved it , which generated new checksum data. I then opened the newly saved bin file and compared the checksum with the old one, and it was Very different.

So, it looked like it WAS a checksum problem!

Just to double check, I then opened the newly saved bin file and then saved it again, just to see if a new checksum is generated with every save. Nope. Newest checksum matched the previous one exactly, and they both were different from my original.

I haven't had a chance to burn this and put it in the cruiser yet, but I think that this will solve the problem. This is the type of solution I've been expecting to find, anyway.

If anyone wants to try my bin file, let me know and I'll email it.

Thanks a ton tabascoloco!

- Matt

Barry · 03-26-07, 07:29 PM

Is it possible to e-mail your file to barry.archer@comcast.net??

Barry Archer
(615) 300-0963

Trollhole · 03-27-07, 11:56 AM

marshall@828rugs.com

Thanks

AnthroCruiser · 03-27-07, 02:09 PM

First of all, a little update.

The Eprom image that I got 1) wasn't corrected by fixing the checksum. It still gave me the error when burned, and 2) when I had someone transfer the tables in it over to a new EPROM image, they were way off anyway (at least for my FJ40).

That said, you can download the non-checksum corrected file here:
http://www.goreorchids.com/GallerySt...emp/2f_tbi.bin

I'll upload the (maybe) checksum correected one later.

- Matt

AnthroCruiser · 03-27-07, 02:10 PM

BTW, I don't have access to my current EPROM image, since I don't have a burner. Maybe in the future, though....

- Matt

jodtan · 04-07-07, 10:37 AM

What really does all this tuning do? I thouhgt GM's computer re-learn by itself unless you got highly modified engine that's totally out of specs. Can you guys pls. clarify all this commotion???

tabascoloco · 05-18-07, 08:06 PM

I fixed it and got our 2F bin file working.

I just finished my first test drive a minute ago...it seems to have a bit more responsiveness. It'll have to "learn" a bit, but I'm pretty blown away by the performance thus far.

I spent hundreds of dollars on this project, and just "had to make it work".

Anyway, I'm going to start playing with it more, as I have the new flash chip adapter, and another spare ECM with the remote control that lets me switch from program to program as I drive to COMPARE.

I now have several WORKING computers with programming specifically for the 2F motor. I wish to experiment with and without KNOCK sensor, etc.

Thanks to everyone who helped.

Mike

Full_Throttle · 07-13-07, 02:17 PM

Hi,
So is the file that is at the link you provided earlier the correct one to get, or not?
Can you post up the correct file, if you don't mind? I am planning on doing this same setup and I would hate to have to re-invent the wheel.

Thanks for your hard work!!

tabascoloco · 01-01-08, 09:44 PM

I've come quite a LONG way and wanted to post an update. I've now experimented with many different programs and mods. I currently have 6 working ECM's and one outfitted with a remote control that holds 16 programs! This allows me to change programming on-the-fly. I'm currently using all sensors (knock, map, temp, VSS, etc), and extremely happy with the results. I have had many cruisers over the years and I've also done many mods, but this one takes the cake. It is like a completely different engine and tranny! Wonderful to drive.

Trollhole · 01-02-08, 07:31 PM

Alright now your gonna have to do a writeup. This will just not do. lol

Questions.

I'm assuming your using TunerPro? RT or regular?

What burner did you go with? I'm leaning towards an Autoprom APU1.

I'm assuming your using the GX switcher? I was thinking using just the dual. Thoughts?

Is your link to the bin above a good one? Care to share any of your other bins with a description?

What was your thoughts on the knock sensor. I'm planning on not running it or a VSS. Thoughts?

I'll host any file you would be willing to send me

marshall@828rugs.com.

What distributor did you go with?

Do you know if the GM ECU will control the fan?

tabascoloco · 01-03-08, 08:36 PM

Quote:

Originally Posted by Trollhole

Alright now your gonna have to do a writeup. This will just not do. lol

Questions.

I'm assuming your using TunerPro? RT or regular? RT but I also like TunerCAT...it's free and simple for minor adjustments, flags, switches, etc...

What burner did you go with? I'm leaning towards an Autoprom APU1. I'd opt for than one if I were doing it all over again...you get the realtime and everything in one package. I bought it all separately. We learn from our mistakes, and I sure learned from mine...this whole TBI conversion has been a big learning experience....and quite costly. Now I think I could do it all over again very cheaply. Also, unless you're very addicted to it, it's probably cheaper and easier to get your rig professionally tuned from a base program on a dyno.

I'm assuming your using the GX switcher? I was thinking using just the dual. Thoughts? Well, since the 1227747's use 4k PROMs, and I'm using the 27SF512 chips (64k), I just program the remote to only use 5 banks of memory. You can set it however you like...I'm using the EX switch and the GX2 socket. I like this remote because it holds more programs (for where you are really experimenting/playing/comparing!)...but you can program it for however many you want, also, it acts as a theft deterrent as you can disable the truck with it removed.

Is your link to the bin above a good one? Care to share any of your other bins with a description? I had hoped for that when I did my project...I finally got help from one cruiser fellow and went from there. The cruiser community really needs a repository for that. I'd be happy to contribute.

What was your thoughts on the knock sensor. I'm planning on not running it or a VSS. Thoughts? I think it's a good idea. Without going into detail, it's cheap. I've not had any trouble at all with it. I mounted mine on the fuel pump block-off plate. I think that's a great spot. No false knocks. Not an expensive add-on like VSS.

I'll host any file you would be willing to send me

marshall@828rugs.com.

What distributor did you go with? GM HEI. Mostly just cause it's simple. Very clean install (coil, etc inside cap). Though I think the FJ60 dizzy I was running before (yeah I swapped side covers out for the large dizzy) is awesome and the best ever made by Toyota, and as a purist I looked hard at 3FE dizzy's and others, in the end, the parts are cheaper and quite proven. You can break down in the middle of nowhere and get the GM HEI stuff anywhere....literally.
Do you know if the GM ECU will control the fan?

Which fan?

Trollhole · 01-04-08, 06:21 AM

Radiator fan.

I'm pretty sure woody would host them for us. But if not I would.

tabascoloco · 01-04-08, 07:36 AM

Oh, regarding VSS, I know ALOT of people say that it's not needed. Many kits don't include it.

After all, you can simply turn it off in the first table of switches.

I use it, as I noticed there are quite a number of things the ECM looks at that have to do with speed.

I think that the notion of it not being needed was started by the claim that unless you have an automatic tranny, it's not important, however, that seems to negate the fact that throughout the programming there are quite a number of other references to it, such as at WHAT SPEED do I do THIS or THAT. Such as minimum speed for Open Loop/Closed loop, etc etc.

I'd opt for it myself.
Also, the knock won't help gas mileage much, but likely would reduce emissions and allows you to advance timing more without ill-effect.

Also, I've gotten other folks' programs and tried them. Some were WAY too rich and generated lots of black smoke their progs ran so rich on my rig...others simply wouldn't idle as smoothly.

There is one particular Chevy program I've found that seems to work great on most cruisers. I've even found it to idle considerably smoother than some that are commercially available and perform very well. I've been quite happy starting there for people and removing EGR, etc. I'm sure it would give most a solid and good place to start.

Mike