And since I was away, doing other things... let me ask you possibly stupid questions. Are the catalytic converters removed? There is set in manifolds and another one in cans after that.

 

my secondaries are removed, my primaries are still there. im not sure how to go about gutting them without tearing up my sexy 2 &1/4" pipes.

they need gutted though.

heres something that ive just now figured out. this might possibly be new thread worthy.

at one point, the car did not run with the CTS unplugged. right now ive got it unplugged, and its been running somewhat good for about 15 minutes. i jumped the CTS plug with a piece of straight wire, and it died instantly. i plugged it back in and it died again. ive got it unplugged right now and its running pretty good.

seems like it runs until the CTS resistance drops to about 200 ohms, and then shuts off.

what would cause this i wonder?

 

in total it ran for about 30 minutes with the CTS unplugged and used 0.6 gallons of fuel before i finally shut it down. far better than the 3 gallons before.

shes such a sweetheart. you can tell how badly she wants to be repaired. it seemed to run better than usual, but like always, if you wind it past 3k, you get a huge backfire out the throttle.

14 in/hg at idle.

 

Take this opportunity to keep it running long enough to properly bleed the coolant.

After that...dunno...I'm still coming back to wiring loom, but I'll defer back to the big guys...

 

its getting dark. if it runs the same in the morning, then i will bleed the coolant properly.

 

When I forgot to plug in right O2 sensor, half of my engine ran funny, making almost metallic sounding backfires. This is after I read in Kirby Palm's book, that H.E. models do not use oxygen sensor's continuously.

 

my O2 sensors are both plugged in and working well. last i checked, they were reading ~0.7v

if i felt like taking a risk on it, i would install a wideband.

 

Damn.... its almost good enough to go for a cruise. im so pumped to romp around these country B roads.

 

I'm sure others will pipe in on this, but my opinion would be that if you're seeing that much of a change, then you still have a wiring problem somewhere involving the CTS.
When unplugged, the ECU interprets the signal as a cold motor, and usually that means INCREASING the fuel mixture to run richer!

 

im thinking a hotter motor runs richer to prevent pre-ignition.

 

Cold motors need a richer mixture because gas doesn't vaporize as easily at lower temps. That's why the older V12's had the extra cold start injectors, to add more fuel.
Think about how the old carbs used to work. With the choke on, a butterfly closed to decrease the amount of air, thus increasing the fuel/air mixture.

 

When everything is working properly the CTS is pretty much done enriching the mixture after 70ºC or so, certainly by 80ºC. After that point it's baro, TPS, and O2 sensors.

Normally unplugging the CTS will kill the engine. Certainly the mixture goes way rich but I've also heard, but never confirmed, that doing so simply shuts off the injectors. This latter makes at least some sense because in my experience the engine dies *instantly*...no chugging, no stumble. It just flat-out shuts off, right now.

I'm not aware of any enrichment function if the engine gets too hot. There are two full-load enrichment switches, though, to add extra full at wide throttle openings.

None of this helps, I reckon

Cheers
DD

 

The ATS works on a *much* smaller temp and resistance range.

If the connectors were reversed....CTS plug on the ATS sensor.... and the intake air temp was 20ºC (about 68ºF) the ECU would see about 300 ohms resistance.....and "think" the coolant was at about 80ºC and would be providing very little, if any, cold enrichment.

In my experience the engine barely responds to a disconnected ATS as it's just a trimmer.

So......

When the engine has continued to run "with the CTS unplugged" ....which is contrary to normal behavior....perhaps it's because it hasn't really been unplugged at all. If the CTS plug was attached to the ATS then the ECU would still be seeing some sort of reading.

<shrug>

I dunno.

The CTS wires are orange/blue and yellow/black, if that helps

Cheers
DD

 

Stumbled on the following article about CTS, poor running and no start:

Testing the Jaguar Coolant Temperature Sensor

 

i unplugged both for good measure.

 

If your car ran with both unplugged, it is 99% certain that there is a wiring fault. I believe that the Lucas HE V12 ECU systemed engine, if functioning properly, will NOT run if the CTS is unplugged or has failed. Most prudent owners carry a spare CTS in the glove box for this reason. A sudden failure stops the car. Therefore, I believe your ECU is getting an incorrect signal from somewhere other than the CTS.

So I remain convinced the rewiring/original wiring you have is deficient in this part of the system.

 

according to my schematic, the TPS loom is wired properly.

 

this is exactly how mine is wired. i forget exactly which ECU pin corresponds.

 

Try putting in a spade connector back near the ECU plug in for the two CTS leads and run a new connector and new temporary wires. Just run them up over the top of the car, and just for the CTS, to bypass the entire wiring harness. This will rule out the loom entirely. There's way more to the wiring loom than just the underhood stuff you've replaced.

When I did control work for commercial HVAC installs, I had a school where I couldn't pick up about half the thermostats on the network. After searching for weeks I found where a careless dropped-ceiling installer had put an anchor right through my network wire.

D

 

so just duplicate the CTS & low side TPS wiring?

5 and 19 are the two pins ill be rewiring, right?