Everything’s been checked every fuse and every relay, fuel pressure,etc. he does see a code for the cps but it’s a newccps and there’s continuity back to the ecu. He also tried using a known working ecu and cps.

 

If there's a code for the cps, then there's obviously an issue. It would be consistent with a no start.

The wires for the cps are shielded wires. I wonder if that might have anything to do with it. I would be surprised if non-shielded wires could result in a non-start? Have you checked to make sure the wires are grounded (on one end only)?

 

Thanks passed this on to the mechanic

 

Jeff,

I assume he's knowledgeable about these AJ16 engines. Many owners have repeatedly chased no-start conditions because they don't accurately diagnose the symptoms and the problem, often just changing parts to no avail.

So, the simple question to him is:

- Does it have fuel spraying out of the injectors when it's cranking? Not just the fuel pump buzzing, or pressure at the rail or clicking of the injectors - Are the injectors spraying fresh fuel in the cylinders when cranking?

- Are the spark plugs sparking when it's cranking? Not just 12v at the coils, or continuity on leads or 12v at the plug top - Are the plugs clean and sparking in the cylinders when cranking?

One or both of those isn't happening. If he doesn't know which, you'll end up chasing the problem like the XJS.

Good luck, Jeff,

Paul

 

Update:
she’s running again. I’m embarrassed to omit this but when I went to remove the bracket as instructed to change the cps I inadvertently remove the bracket that held the sensor not the plug end. Working by feel when I reinstalled it I used a wrong mounting hole and the sensor was slightly off causing the cps error I mentioned earlier. Mechanic figured that out but claims my ecu is bad and only got her running by using a similar ecu from another jag. Anyway just sharing my stupid mistake and want to thank all who offered help with this. Can’t wait to get her back as the warmer weather is calling
Regards,
Jeff

 

Jeff,

No shame, we've all made schoolboy errors trying to fix our cars!

Others may disagree, but I'm surprised the ecu was "faulty" Corroded pins, Yes,possible, but the circuits are pretty robust IME. Anyway, glad you've got it sorted. I'm sure you're keen to get it back on the road!

Cheers

Paul.

 

Ok the saga continues. Sent mechanic a new ecu with exact matching numbers as original he installed it and also replaced a leaking oil pressure switch while it was up on the lift and change oil and filter. Said the car was running beautifully untill he lower it to the ground then is just sputtered and died. He said there’s fuel pressure but no spark. Back to square one. Urghhh!

 

Jeff,

That's very frustrating for you. I would ask him the same questions I wrote in March:

- Are the injectors spraying fuel when cranking? Not just pressure at the rail, not just clicking of an injector - Are they spraying fuel when cranking?

- Is the spark plug sparking when cranking? Not just voltage at the coil or the plug - Is the plug sparking when cranking?

One or both of the above isn't happening. Unless he's pulled an injector and a plug and tested both when cranking, you're chasing shadows again.

Good luck,

Paul