LS 1 engine wiring question

**insadj2** · 09-22-2013, 05:27 PM

I have an LS 1 installed in a 36 Chevy. I am trying to hookup the tach and need to know which pin/wire to use from the ECM. Any help would be appreciated.

**pajeff02** · 09-22-2013, 05:37 PM

Deja Vu -- just answered this question... let me go find it for you.

**pajeff02** · 09-22-2013, 05:38 PM

On the PCM, Connector 2, Pin 10, white wire for a tach signal.

Welcome to the site!

***SMWS6TA*** · 09-22-2013, 05:39 PM

pls post pics........would love to see that ride!!!

**pajeff02** · 09-22-2013, 05:40 PM

^^ Agree. We have a Classic Muscle section - use Photobucket (or another photo sharing site) to upload the pics. Then simply copy and paste the [IMG] code into your post on here.

**insadj2** · 09-22-2013, 05:46 PM

Originally Posted by pajeff02

On the PCM, Connector 2, Pin 10, white wire for a tach signal.

Welcome to the site!

Not a lot to look at right now. Have all the paint work completed, engine in and running. Now installing gauges and dash. May need help with cruise. This has been an 8 year build. An older old school guy was helping me and since the first installation before tear down for paint he had a stroke and doesn't have the best memory. Soooo now he and I had rewiring again. I forgot to mention that I used a Fast wiring harness and a quickwire fuse box/harness. Will try and post some pics later. Thanks for the help. This has been a journey buy nearing home base.

**pajeff02** · 09-22-2013, 05:59 PM

Only 8 years? I think I started my '66 Buick project in 1995... and it's still just a rolling chassis with an engine and transmission.

**insadj2** · 09-22-2013, 06:17 PM

Sorry. Tried to insert code but site would not allow me. Thanks.

**pajeff02** · 09-22-2013, 06:47 PM

We have the site security settings tweaked right now to knock down spammers. You might need to hit 10 posts and/or 10 days to post pics. I keep forgetting about that. Looking forward to seeing this project.

**insadj2** · 09-26-2013, 10:44 AM

OK. Told you I would be back. Got my tach working with white wire from pin 10. Now working on speedo. Think it is green wire from pin 5 but unsure. Any help? Thanks in advance. And thanks for the help with the tach.

**insadj2** · 09-26-2013, 03:06 PM

Can someone advise witch pin is the speed control on the ecm. I am now trying to hookup the speedo

**pajeff02** · 09-26-2013, 04:41 PM

Sorry... was out doing some work this evening and just logged in. Let me go look.

**pajeff02** · 09-26-2013, 04:47 PM

The Vehicle Speed Sensor (VSS) is part of the transmission, not the PCM. Look for the green wire in terminal A (the rear one) and purple wire in terminal B (the front one). The green wire is your VSS ground and the purple wire is your VSS signal.

**insadj2** · 09-26-2013, 04:53 PM

Originally Posted by pajeff02

Sorry... was out doing some work this evening and just logged in. Let me go look.

No problem. Been in shop tonight trying to get speedo to work. Have classic gauges, with adapter sn74 with dip switches. Trying to find input wire. Tried 21, 22 and green wire #9 I think next to tach white wire.

Any help would be appreciated. I will check back when I get to house. Leaving garage.

**pajeff02** · 09-26-2013, 04:55 PM

Check the post above yours... I beat you back by 6 minutes with a reply!

**insadj2** · 09-26-2013, 04:56 PM

Oh OK. Will try those tomorrow night. I did notice my gauges say 18 PPM and looks like the ls1/4l60e puts out 8? Any kowledge about that?

Thanks again. Sure glad I found this site.

**pajeff02** · 09-26-2013, 04:58 PM

I'll probably have to go crack my shop manual open and read up on that one.

**insadj2** · 09-26-2013, 04:58 PM

Also any idea on which pin numbers.

**pajeff02** · 09-26-2013, 05:04 PM

Just checking on our site, I see reference to there being 40 teeth on the reluctor for the 4L60E VSS.

**pajeff02** · 09-26-2013, 05:58 PM

Looks like you can also find the purple VSS signal wire on Pin 21 of your red connector at the PCM. Going to see if my scanner will let me upload a page from the manual this evening.