speedking

I have a 94 Formula and am having some problems with TunerCat. I keep screwing up my PCM. I have messed up 3 in the last 2 days. I first read my stock computer, saved the file as a .bin and then took out VATS and C.A.R.S, then saved as a different file name to preserve the original if I had a problem, then I clicked on program PCM and it got about 3/4's of the way complete, then I got an error that said "Cable Failure", I clicked OK, then it said "Attempting Restore" it sat on that screen for about 45 minutes, then I noticed I my laptop had locked up. I could here my PCM just clicking until I took the key out of the ignition. I followed the procedure to reset the PCM, by disconnection the battery and trying to rewrite the program, but my cooling fans came on and the PCM kept clicking. I went to the dealership and got another PCM, tried it again, same thing happened, programming gets 3/4 way complete then locks up, but now it seems as if the USB port on my laptop isn't working either. I got a third PCM from the dealership and the car runs and drives right now, but the speedo is way off and it runs quite rich. I also am having a hard time with the shift select. It forces from first to fourth and that's all. I am nervous about trying to reflash this PCM, because I don't want to ruin another one. Any suggestions?

BTW, I am using a brand new IBM T40 thinkpad with 1 gig of ram on XP Pro. I also have a USB cable from AKMcables. I purchased the $EE Def file from TunerCATS, but am using the free trial version of Tuner. Would that matter? I am tempted to pull my desktop out to the garage and try that, but am hesitant about ruining another PCM. Has anyone ever wrecked a PCM with a desktop? I have searched and found that some people have used an older laptop with more success than a newer one, but what would that matter? I disabled the IR port as suggested and closed all other applications. I am totally lost.

madwolf

No, it doesn't matter that you are using the trial version of Tunercat. It should upload fine. There is a problem with the laptop, cable or something on the car side.
The reason your speedometer is off and why you're having the other problems is because PCMs come with a base tune from the dealer, but it isn't an F-body one. I beleive it's a Caprice tune, or perhaps something they made that would "temporarily work" on all LT1 cars. You need to have it reflashed before it will run correctly.

You can either have the dealership reflash, you can try it with your desktop, or if you want, you can send it to me for a reflash. I can also repair these computers if they fail.

speedking

Is a desktop safer for flashing than using a laptop? I don't think that the cable is bad, because I thought they were all tested on an LT1 computer before they were shipped. I don't really know what could be on the car side that would hinder me from loading a tune. I have a brand new battery, because when my first pcm got messed up I thought it was due to low battery voltage, but I had the same problem with a fresh battery. I had no accessories on in my car at the time I was trying to flash, and I even had my amp unhooked from the battery for fear that it would drain the battery. I really don't want to take the car to the dealership to have it flashed.

madwolf

I think desktop flashing is a bit safer, so you can give that a try.
Did you try doing a read of the current program first and see if that goes through all the way?

radik

usb is scary.. tell him that ion.. The default tune has the same advance and a/f tables as a stock camaro, without a vin is stays in limp mode?.
My guess.. good luck man it sounds like the usb, I don't like the idea of changing methods after so long try serial if you can.

In another thread about failing pcm's and usb, basicly it seemed the problem was the usb was set to 1.1 instead of 2.0 ie your usb port in your bios is set to slow; but when you think about the amount of data needed to program I kinda find that hard to swallow.

speedking

I had no problem reading the PCM with USB, but writing is where I ran into some trouble.

Why is USB Scary? Is there a USB to RS-232 to use? The cable I have has the GM1 Connector for the ALDL with a 3 ft cable with a 25 pin female connector going into a 25 pin male connector with a female USB connector, then it has a standard USB cable connected to that.

How can I check what speed my USB is set at?

speedking

What should my port settings be for the USB, I have 9600 Baud, 8 data bits, parity none, stop bits 1, Flow Control Xon/Xoff. On the advanced tab, I have Com Port 4, Recieve Bytes 4096, Transmit Bytes 4096, Latency Timer 1, Minumum Read Timeout 0, Minimum Write Timeout 0, Serial Enumerator is Checked.

Are these correct?

Alvin@pcmforless.com

I use USB cables from moates.net with no problems at all. I try to be as careful as I can when flashing cars. If I where a DIYer I would socket a PCM and buy a few extra chips so you dont' get stranded.

speedking

Well I hauled my Desktop out to the garage and finally got a good write. I don't know what was wrong with the laptop, but I am glad the desktop worked. Thanks for all of your input guys.

Later,
Kevin

Alvin@pcmforless.com

Is the IR port on the laptop disabled?

speedking

I disabled it in both the bios and in Windows, but it still wouldn't work, I am probably just going to put my desktop on a shop cart and keep it in the garage. Another question though, does it matter how long the USB cable is? Right now I have a 6 foot cable, could I use a 20 foot cable?