Dwell Stuck at 50% am I correct to suspect the O2 sensor?

[Bitsyncmaster]

I just did the plug swap and it started right up.

So, I think that means the cold start valve is good, right?

After that I tested the pins of the TTS to engine ground and found that one pin was about 30Ω and the other was 0.2Ω -- both of those values sound right. The electrical clip that clips into the TTS sensor is badly damaged, I wonder if that clip isn't making a good contact to those TTS pins...

What else can I check?

There are connections also in the bulkhead connectors. My car had a bad bulkhead connection that made the CSV fail. I would suggest you use an ohmmeter to verify all the connections from the CSV to TTS are good. The bulkhead used a few pins just to join some wiring with a jumper on the back side of the bulkhead. Those are not documented.

[David T]

If it started right up cold with the plug swap it proves;
a) the CSV is good and works
b) for whatever reason the CSV was not operating on it's own.
The next step is to check the wiring and connectors. I have seen the plug to the TTS deformed and incorrectly plugged into the TTS causing it to burn up inside. I have seen the TTS installed with teflon tape effectively preventing it from connecting to ground. I have seen the wire going to the starter either disconnected or connected to the wrong terminal. Let's see what you find. Trace the system out wire by wire.

[spikeygg]

So, I just went out and checked some of the wiring. It looks like the two pins at the sensor plug are shorted together... is that normal? I even pulled the two white bulkhead connectors and they're still shorted together at the TTS connector.

What I mean is that WR (32) is shorted to UB (47). Any ideas where these wires may be shorted?

edit
I found that the CSV has those pins shorted. When I pulled the plug on it, the short went away. I'm guessing that's normal? Seems that the wiring is good and separate from the TTS plug to the bulkhead and to the CSV.
end edit

[Ron]

That sounds normal.

Unplug the TTS. At the Hot Start Relay, jumper the UB wire to the B (ground) wire. If it still starts right up COLD, the TTS or its wiring is bad. Check the TTS socket-plug, WR wire for 12V while cranking, and its UB wire for ground (while the jumper is still in place). If OK, replace the TTS.
Don't forget to remove the jumper or the engine will flood....

[spikeygg]

I'm trying to figure out if my starter is hooked up right to WR. I can see the White/Red wire but I can't quite see how it plugs into the starter and the heavy red cabling is in the way and difficult to move. Googling around for "DeLorean Starter" images result in pictures that don't quite look like my starter. Any idea if this looks correct? Can someone shoot a photo of their starter plugged in? Maybe that WR wire is easily visible in the same spot...

Starter.jpg

[WHO1DMC]

I'm trying to figure out if my starter is hooked up right to WR. I can see the White/Red wire but I can't quite see how it plugs into the starter and the heavy red cabling is in the way and difficult to move. Googling around for "DeLorean Starter" images result in pictures that don't quite look like my starter. Any idea if this looks correct? Can someone shoot a photo of their starter plugged in? Maybe that WR wire is easily visible in the same spot...

Starter.jpg

This might help.
http://dmctalk.org/attachment.php?at...8&d=1571608950

Dave B.

[Ron]

The WR wire should have 12V on it while cranking, only.
If you follow the steps in my previous post, in order, any problem with the CSV or the wiring for it should be identified.

[spikeygg]

That sounds normal.

Unplug the TTS. At the Hot Start Relay, jumper the UB wire to the B (ground) wire. If it still starts right up COLD, the TTS or its wiring is bad. Check the TTS socket-plug, WR wire for 12V while cranking, and its UB wire for ground (while the jumper is still in place). If OK, replace the TTS.
Don't forget to remove the jumper or the engine will flood....

Ron, I have Dave's solid state hot start relay. I just went out and tried to find a way to jumper UB to B. I don't have male spade connectors available so I pulled the hot start relay out a little and use an alligator clip from the UB to the B and it still wouldn't start. Not sure if using the relay pins is a good idea or not but it didn't seem to make a difference.

[Ron]

Ron, I have Dave's solid state hot start relay. I just went out and tried to find a way to jumper UB to B. I don't have male spade connectors available so I pulled the hot start relay out a little and use an alligator clip from the UB to the B and it still wouldn't start. Not sure if using the relay pins is a good idea or not but it didn't seem to make a difference.

Not a good idea usually...Jumpering different wires together at a socked/plug is usually done when disconnected.

The test(s) assumes there are no modifications. The hot start relay and some of its wiring was abandoned by DMC. If Dave's hot start relay requires wires to be added/changed, the test is not reliable.
Otherwise, remove the relay, confirm that it starts COLD with the plug swap test. Then repeat the tests.

Since it started right up when you did the plug swap, we're assuming the CSV is good but it's not being energized. So its WR wire is not bringing 12V to it or its UB wire is not grounding it (the TTS's job). Jumpering UB to B should ground it and if the WR wire has 12V, the CSV will energize and the engine should start cold (as with doing the plug swap). If not, the TTS is probably bad. This can be confirmed by disconnecting the TTS and checking for continuity...The TTS's metal case (ground) should have continuity to its WR and UB terminals when COLD. [When it is HOT (from cranking), the TTS's metal case should have continuity to the WR terminal only).

If in doubt, when the engine is COLD and the starter has not been used for several minutes, put the CSV in a bucket and see if it sprays while cranking.

[spikeygg]

That sounds normal.

Unplug the TTS. At the Hot Start Relay, jumper the UB wire to the B (ground) wire. If it still starts right up COLD, the TTS or its wiring is bad. Check the TTS socket-plug, WR wire for 12V while cranking, and its UB wire for ground (while the jumper is still in place). If OK, replace the TTS.
Don't forget to remove the jumper or the engine will flood....

Ok, I'm back at it now that it's nice outside again. I did the jumper with Dave's solid state relay removed. The car still doesn't start right up. I checked the voltage at the TTS while jumpered and cranking and it hit just over 10V. With the UB not jumpered to ground the TTS only sees about 1V while cranking.

I bought a new TTS from DeLorean assuming it was bad but the new one exhibits the same response as the old one.