What Happens When...

[Happy Jim]

I have a friend that is putting an LS1 into an AC Cobra replica, he's bought the VATs module but didn't think about the O2 Sim module (installation doesn't have provision for rear O2 sensors).
I'm happy to go and flash his ECU out to sort things out - but he's Miles and Miles away so would prefer to wait until I have a reason to drive up there.
Alternative is to get the O2 Sims shipped to UK from the states (but it's expensive!).
Question?
Other than throw a MIL code or 2 will the ECU let the engine run as normal without the O2 sensors (or does it go into some Limp Home Mode) - in which case he can live with it for a while.

Thanks

Jim

[joecar]

It should run, it will stay in OL.

[swingtan]

Correct, std. Gen III LS1 PCM will look for valid O2 signals and if they are not found, will revert to OL mode. To give an example, 2 nights ago I updated a tune on a friends car and as he didn't have a WB O2 bung in his exhaust, I just pulled one of the NB O2's and put the WB in there.

When running the car, the PCM sensed that one of the O2's was not responding ( because it was hinging in fresh air, tied up to the side of the gear box ) so it just stayed in OL mode. This actually saved me from needing to alter the tune to stay in OL with VE tuning, so it was a good thing.

Just remember that you will want to get the VE dialed in pretty well to run it in full OL mode, as there will be no trimming to help correct the mixtures.

Simon

[Happy Jim]

Joe, Simon,

Great info many thanks - I have a plan now :grin:

Cheers

Jim