Cascade Crew

flea · Posted: Mon Dec 05, 2011 5:11 pm Post subject: VSS

I need to ensure that my VSS is sending 4000 PPM to the ECM.

How do I go about this. Is there a cable and a bit of software that I can get to look to see whats going on. I guess I'm asking about data logging, I don't necessarily want to make changes without adult supervision (can you imagine all the ways I could mess that up Shocked

) But I do need to know that I have the correct ppm going on.

aaron_sK · Posted: Mon Dec 05, 2011 8:21 pm Post subject: Re: VSS

flea · Posted: Mon Dec 05, 2011 8:39 pm Post subject:

Ok. it is the original VSS. The ECM is a 7730, what I have been able to find is that I need 4K to the ECM or it runs like dodo.

I can't find any info on which speed sensor I need to get, any suggestions?

Edit. the buffer box is robbing some of it, isnt it. would this take care of the problem?
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aaron_sK · Posted: Mon Dec 05, 2011 8:49 pm Post subject:

You need a '90 or newer multiport motor; TPI, veesix, or very early LT1.

There is also some scamming you can do with the ECM itself IIRC. We just had a thread on this not long ago...

chevymad · Posted: Mon Dec 05, 2011 8:58 pm Post subject:

He has a 91 VSS allready.. and the same vintage ecm. Don't think its the problem.

Or does tbi have a different VSS?

aaron_sK · Posted: Mon Dec 05, 2011 9:02 pm Post subject:

TBI retained the old-style VSS through '92.

Multiport cars went to the new style in '90.

*Edit: Quick check shows the following interchange:

'91-'93 Buick Roadmaster
'90-'93 Cadillac Fleetwood
'91-'93 Chevy Caprice
'90-'92 F-body 3.1L
'90-'92 F-body 5.0/5.7L TPI
'93' F-body 3.4L
'93 F-body 5.7L LT1

chevymad · Posted: Mon Dec 05, 2011 9:07 pm Post subject:

And there's your answer Jim.. you need to replace your brand new VSS...

aaron_sK · Posted: Mon Dec 05, 2011 9:11 pm Post subject:

Still got that receipt?

blue89 · Posted: Mon Dec 05, 2011 9:23 pm Post subject:

You can set a multi meter to HZ and then measure it. 60mph should get you 66hz (4000ppm*60mph*1hr/60min*1min/60sec=66pps or 66hz)

flea · Posted: Mon Dec 05, 2011 9:57 pm Post subject:

Leejo2005 · Member Joined: 12 Jul 2009 Posts: 466 Location: Kennewick

Firebirds got the 4K VSS a few years before the Camaros did. I'm not sure what year it started at but my '88 drivetrain has one.

flea · Posted: Tue Dec 06, 2011 6:06 am Post subject:

cool, so it sounds like I need a bird VSS from the same years along with bypassing the buffer box and I should be golden.

Al Hasse · Posted: Tue Dec 06, 2011 8:21 am Post subject: