Help! Scangauge Causing Crank No Start

[maxswasser]

Pretty much as it sounds. I have a scangauge II on an 01 7.3. When I pull the scanguage out of the OBDII connector, lights on the dash flash when I crank it over. It sounds like it starts to catch, but then doesn't fire. No check engine light until it's cranking.

I'm trying to install an Edge CTS3, EGT probe and a HydraChip today. I plugged in the CTS3 and scanned for codes, but there's nothing - while it's not running. It won't start with the Edge monitor/s either.

Any ideas? What could cause this? Should I plug the scan gauge back in, start it up and remove the scangauge while it's runnicang?

Thank you all! Wish I could buy you all a beer over the internet.

Max

[1der]

Is the hydra installed on the PCM ?
Where are you located?

Let's see if I understand:
original config -
Scangauge installed and no tuner - starts and runs fine.

Change 1 -
disconnect Scangauge from OBD2 port (tuner not installed) and you get the no start?

[carringb]

If there’s no check engine light when on, no crank, then the PCM is not getting power through it’s dedicated circuit. Check the fuse, after disconnecting anything connected to it.

[maxswasser]

Originally Posted by 1der

Is the hydra installed on the PCM ?
Where are you located?

Let's see if I understand:
original config -
Scangauge installed and no tuner - starts and runs fine.

Change 1 -
disconnect Scangauge from OBD2 port (tuner not installed) and you get the no start?

This is correct. I just plugged it back in and it starts fine. There are three codes stored, but it will only read the first one to me which is a low voltage code PO562.

Do you think it's safe to see what happens if I remove the scangauge while it's running to plug in the edge monitor?

Thanks!

Carringb - it cranks, just doesn't fire

[1der]

Was any attempt made at installing the Hydra on the PCM?

[maxswasser]

Originally Posted by 1der

Was any attempt made at installing the Hydra on the PCM?

No, I figured I should deal with this issue first. Should I try?

Also, I’m in New Haven, CT

[1der]

Sounds like maybe a bad ground and the system may be grounding via the SG2.

check battery terminals

check grounds at the power distribution module in the engine compartment especially the strap that goes to the front sheet metal behind the driver headlight area. Do not rely on a tight connection. Remove and clean and reinstall.

Is the "wait to start" light coming on when you first turn the key?

I would not attempt install of chip yet. I agree solve this issue first.

[maxswasser]

I cleaned this terminal. It looks like a small connection has broken off. Could this be it? I can’t find a wire that would go there anywhere.

[1der]

The missing wire is probably not anything original, maybe for an aftermarket accessory. But the other two, if you did not already, remove the bolt, clean the surfaces with a bit of sandpaper, clean the bolt head and threads, clean the hole, and reinstall.

Not saying that is the issue as there are lots of grounds but that one is pretty major.

If I get a chance I will look at my factory wiring manual and see if there is a troubleshooting chart.

[maxswasser]

So I got the edge monitor up and running. It’s reading 7.5 volts. The Scangauge is reading normal volts.

What about the Scangauge plug in the OBDII connector would be keeping the volts up?

I’m open to ideas. Thanks for your help. Truly amazing what people are willing to do for others on here.