What have you done to your DeLorean today?

[Jonathan]

Jonathan, Have you checked your CO/Dwell?

Hey Ron... I have not. Ever, actually. I hadn't ever really needed to since I got the car, but I'm thinking it might be time I finally figure it out. I've seen a number of threads and videos on the subject so I should be ok there. Just need to track down a meter to be able to read that sort of thing.

[Bitsyncmaster]

Hey Ron... I have not. Ever, actually. I hadn't ever really needed to since I got the car, but I'm thinking it might be time I finally figure it out. I've seen a number of threads and videos on the subject so I should be ok there. Just need to track down a meter to be able to read that sort of thing.

You would want to check the dwell before changing the O2 sensor. If something is wrong with the lambda system, it's best to fix it first so the new O2 sensor does not get dirty.

[Jonathan]

You would want to check the dwell before changing the O2 sensor. If something is wrong with the lambda system, it's best to fix it first so the new O2 sensor does not get dirty.

Will do, Dave. I'll track down a dwell meter and see what it says. I suspect this was checked in that first year I had the car (2007) when I had a mechanic doing most things for me. I didn't find any notes about it in any of the paperwork, so maybe not though. It seems like my fuel mileage got a bit worse this summer, but that's only a guess without a working speedo/odo. Last year (going to Dayton and back for example) it was in upwards of 27 MPG and now I think it is closer to 21 MPG.

[Bitsyncmaster]

Will do, Dave. I'll track down a dwell meter and see what it says. I suspect this was checked in that first year I had the car (2007) when I had a mechanic doing most things for me. I didn't find any notes about it in any of the paperwork, so maybe not though. It seems like my fuel mileage got a bit worse this summer, but that's only a guess without a working speedo/odo. Last year (going to Dayton and back for example) it was in upwards of 27 MPG and now I think it is closer to 21 MPG.

If your dwell is off the correct setting, that will affect MPG and mixture while your engine warms up. Is your adjustment plug cap already drilled out?

[Jonathan]

If your dwell is off the correct setting, that will affect MPG and mixture while your engine warms up. Is your adjustment plug cap already drilled out?

Yes, the tamper proof cap has never been there as long as I've owned the car. I have the plug from DMCH with the little handle and hook coming off it to keep it sealed.

[Jonathan]

Pardon my ignorance, but where exactly is the other end of the oxygen sensor plugged in to?

I thought I knew, but apparently I don't. I had thought it was the one that becomes the blue wire going through the grommet in the firewall, just to the side and below the ballast resistor and which comes into the electrical area behind the driver's seat. It doesn't seem like that's the right one though as the connector isn't the same and the engine side of that one disappears into the centre of the engine (from what I can tell).

I can see my oxygen sensor from above looking down at the exhaust pipe, and the black wire coming off of it disappears into an opening in the frame just in front of the centre line of the left rear wheel, but then I can't see where it goes. I hadn't thought the oxygen sensor wire was very long (two feet?) so didn't think it could be going very far and yet I still can't find it. Does the car need to be up in the air to see or access the connector?

[Bitsyncmaster]

Yes it the O2 plugs into a connector near the drivers rear wheel. The other side of that connector is a blue (I think) wire that runs to the lambda ECU.

[Horsebox]

You could always reroute the oxygen sensor wire so that it still goes through the bulkhead to the lambda ECU, but has a connection that is easy to get at in the engine bay. Makes troubleshooting the lambda system much easier. No more scrabbling around underneath the car trying to find when the lambda sensor cable goes.

[DavidProehl]

The NorCal DMC Club went on a drive around Lake Tahoe last weekend. Here is a short (3:20) video I made from the drive:

[Jonathan]

A little update:

- I finally found the O2 sensor connector. I confused myself not realizing the engine bay side connector I could see corresponded to the interior side hidden by carpet, and the interior side wire I could see WAS the opposite end of the O2 connector. I jacked the car up and double checked the connection actually by reaching over the top of the wheel while it was suspended. All good there.
- I ordered the Actron CP7605 dwell meter off Amazon and it'll be here next week.
- in the meantime, drove up to my hometown for their car show. Was glad it ended at 9 pm and not any later, like say 10:04 pm... considering where I parked that is.

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