How to set timming on 97 5.7L Vortec?

**fierodough** · 03-28-2007, 10:48 AM

I have a 97 k1500 Suburban with a 5.7L vortec OBDII.

How can I adjust the timming? I know it's with the distributor. But do I need to put the computer in diag mode or something so it doesn't compensate for my adjustments?

Thanks in advance!
Eric

**MrShorty** · 03-28-2007, 11:01 AM

As I understand it, you have to have a scanner that will read the "cam position sensor retard" parameter. I also understand that not many scanners can read this parameter. From what I understand, once you can read this parameter, it's a simple matter of rotating the distributor until this parameter is +/- 2 degrees or something like that.

**fierodough** · 03-28-2007, 01:31 PM

shiat... OBDII can be so sweet and yet so complicated...

I think I have my timming too far advanced... I think I have a ping problem, but not 100% sure what that sounds like.. Sounds a little like a squeeking alternator bearing but oly under load.

**MrShorty** · 03-28-2007, 06:42 PM

The best description I've seen for pinging is a dull "marbles rolling around in a can" kind of noise.

**wildmans92** · 03-30-2007, 01:11 AM

What does the trucck do? is it missing idling rough etc. honestly i dont thing you have a pinging problem because the computer would retard timing to eliminate it.

**fierodough** · 03-30-2007, 09:32 AM

Originally Posted by wildmans92

What does the trucck do? is it missing idling rough etc. honestly i dont thing you have a pinging problem because the computer would retard timing to eliminate it.

It idles rough when cold. New temp sensor was installed so that's not the prob. I'm due for a tuneup.

I canhardly describ the sound... It's a squeeky ticking sound. Sorta like your dash vibrating and rubbing against some trim. I thought it was my alternator or waterpump starting to go. But it only happens under load (acceleration) not when I rev the engine in neutral.

There is NO loss of power when the sound is there.

I do have a constant high idle problem... sets off code 507...

My knock sensor looks old and rusted. I may replace that.

I'm starting to suspect EGR...

Really the only thing that could shed some deffinite lite on the problem is a coomputer diagnostic. But I can't find a tech locally that will diagnose the truck with a TECH-II and let me see the readings. All they do is use the readings for their own diagnostic to solve a problem. I would like to know all that the computer sees...

Thanks for your help and I welcome any advice!

Cheers!
Eric

**unplugged** · 03-30-2007, 09:57 AM

fierodough, check out http://winaldl.joby.se/ for ECM scan tool that is free. It connects to your pc.

"WinALDL is a program that reads the ALDL data from some supported ECM types. The data is presented in a way that will help when tuning a car after engine modifications. A simple hardware interface must be built to convert the ALDL data stream and make it compatible with a PC serial port
The original idea for this program came from Ken Kelly. At first we just wanted to write a good free scanner for the 1227747 ECM. Then We added another one ... and another ...
I have used information found on the internet when writhing this software. I don't have access to the ECM's supported, so I can not test everything. Please let me know if you find something wrong and I will try to fix it. If you have a 160 baud ECM that is not supported you can still use the raw data logging. I might be able to add support for more ECM's, but I need information about the 160 baud data stream for that ECM."

**Cableguy** · 03-30-2007, 12:14 PM

Originally Posted by unplugged

fierodough, check out http://winaldl.joby.se/ for ECM scan tool that is free. It connects to your pc.

"WinALDL is a program that reads the ALDL data from some supported ECM types. The data is presented in a way that will help when tuning a car after engine modifications. A simple hardware interface must be built to convert the ALDL data stream and make it compatible with a PC serial port
The original idea for this program came from Ken Kelly. At first we just wanted to write a good free scanner for the 1227747 ECM. Then We added another one ... and another ...
I have used information found on the internet when writhing this software. I don't have access to the ECM's supported, so I can not test everything. Please let me know if you find something wrong and I will try to fix it. If you have a 160 baud ECM that is not supported you can still use the raw data logging. I might be able to add support for more ECM's, but I need information about the 160 baud data stream for that ECM."

Nice find on the internet, Thanks unplugged I always wondered about that.
Siskel and Ebert give it two thumbs up