Put your finger on the fuel pump relay and feel for the 3rd click as the pump turns back on after the ECU sees rotation by the Crankshaft Position Sensor . You appear to have the 3 - 5 second primer charge but eats it up and starves .

You can hotwire the fuel pump to stay on by bringing power to the forward most # 1 pump relay socket ( this would verify relay control issues like M'Lady P. had when I bought her .

High current hazard so use a blade type connector in the relay and the last arcing contact at the battery

You may have something intermittent like on mine .

The # 2 pump does not turn on until 4000 RPM and back off at 3200

You can jumper the # 2 pump as well but mine does not have one so I can't tell you the physical location of the socket you want to put power into just that it is a heavy Blue / Red one

 

Is it safe to keep the fuel pump on all the time by bypassing that relay permanently, or is this just for testing? Tracing the fuel pump control circuit for intermittent shorts is a bit daunting.

I'll let you know about the 3 clicks on the relay when I get a chance. Need somebody to stand in very very cold weather outside with me

thanks,
John

 

No , you can put a temporary clip on the battery or rear fuse box terminal . Mine was wired though the accessory relay socket position as I got it and was live with the key switch , found the original fault was in the relay control circuit repaired back to the designed # 1 pump relay . Their repair was faulty as the rubber glue on the black electrical tape migrated into the twisted conductor wires .

The test configuration can be used as a temporary fix , but it will be live at all times .

You can do the # 2 pump the same way on your SC model .

One of the pumps should work with the matter of the one fuel filter to consider , easy change when warm .

Any questions . just ask . My original owners fault was with the RS3 connector pin 22 that goes through the behind right fwd wheel well .

This is in no means the magic bullet , but eliminates some things toward your resolution .

 

I did the fuel pump relay test... all fine on that end.
The "stall on very cold weather" is I think due to a clogged exhaust...ice collecting somewhere. Here it is explained.
https://www.jaguarforums.com/forum/x...orking-108330/

I did upgrade to a new computer ECU with latest EPROM and that might have solved the stall on warm weather. Now getting a P0500 (bad wheel speed sensor) and P0123 (Throttle out of range) with new computer but all runs great, I guess I need TPS calibration but don't know anybody with the PDU...

Thanks!~

 

The green / yellow wire should read 0.60 volts + or - 0.02 volts with the key in the on position and engine not running . As you slowly twist the butterfly you should see a steady climbing voltage and no bips to zero . Best seen on a old school needle meter .

With the P0500 you can remove and clean the face of the sensors as they get clouded over with debris . The sensors will read about 1300 ohms as a fundamental test , not a functional test . The pairs are marked as a color group in the print .

 

Have you checked the temperature SENSOR readings this is the 2 pin socket on the thermostat housing? Sounds like the engine isn’t getting the enrichment for cold tart.

 

Thanks for the tips. The new Throttle Position Sensor error code is only present with the new ECU (with very latest AL EPROM) so I imagine a Throttle Adaptation Reset would fix it. The Speed Sensor error was not present with my 2 other ECU's...but likely related to my ABS Light on. The Speed Sensors are rusted tight in rotors with no way to remove...
No big deal. ABS Light usually goes on above freezing temp, stays off when very cold so obviously a bad connection/solder joint and I plan to eventually replace ABS unit also.
I drilled some weep/drain holes in my muffler...lots of water seeping out (first time in 30 days that the temperature is above freezing. And I keep the car outside all the time).

 

So as a summary: the car would stall on startup without gas pedal pumping. This happened with 2 different ECUs (AH EPROM). With the other ECU (newest EPROM AL) the stall hasn't happened again.
The no-start condition was due to a muffler clogged with ice.
I am also inclined to think that the catalytic converter (probably original from 1995) is useless, half-clogged and possibly causing the stall problems. That's for another thread.

 

You can manually set the Tps, as i did, its possible to loosen the screws with a small ratchet, with the throttle body on, with bellow removed, i enlarged the holes on tps, and probe middle wire on connector with wire/paper clip then attach positive lead of multimeter, use manifold for earth, move tps until you get .6volt reading, and tighten, and recheck. I used wing nut bolts, so it was easier to tighten.

 

Thanks