I replace the wire that comes from the start relay to terminal 3 of the diode at Dougs suggestion. There is power from the post the wire is connected to at the start relay. But no power at terminal 3 of the diode.will the rest as you posted. thanks

 

I am stuck at the diode. The start relay has power at the white/yellow post which sends power to terminal 3 at the diode. No power at terminal 3. If the diode is bad and not using the power from the start relay I would assume the diode is bad. But iam reading or not understanding is why the injectors dont fire including the cold start. I know its been said not all of these work together.
So what I have is I think a bad diode and or a faulty start relay thats showing power but might have an internal fault that not sending the right power???
Also the injectors ..Iam having a hard time seeing if they have power. bare with me im POded at the situation.

 

update......i have pwer at the injector resister pack.

 

did you replace the fuel pump???

 

yes its all working fine....fuel at rail is 38psi

 

still no start?

 

canks but no start

 

can you list the parts you have already replaced?

 

fuel filter, pump, wires cap router, plugs,, the black thing in the amplifier, feul relay.

 

oh coil to

 

im just wondering about a balast.... is it on the coil?? if so someone told my son to get ri of it.. and tie in the wires to the coil....12v coil

 

the ballast is a square piece of white ceramic that used to come attached to the coil, but Jaguar eliminated it.

yes, remove that darned ballast, connect the white wires to the Positive (+) terminal of the Coil. Do you mean it is still there?

it looks something like the picture below:

 

done

 

OK, good. You have power at the resistor pack....presumably at the two brown/slate wires,yes?

You also have 38 psi fuel pressure at the rail, which is fine. Should be 36 psi but 38 is close enough.

A few days ago you mentioned that you still have spark, correct? If so, good.

Did you ever determine if the injectors are pulsing?

The injectors get voltage from the resistor pack, and we already know that the injector pack is getting voltage. Now, is the voltage getting to the injectors? With the key "on" you should have 12v at the injectors...so check for that. Pick any injector and check for voltage on both wires. Both should show 12v with the key "on".

The injectors are grounded by the ECU so when cranking (or running) one of the two wires at each injector changes to ground. This will result in a flickering of your test light on the grounded wire (the wire comong from the ECU) or, if you have one, your injector "noid" test light. Voltage on the wire from the resistor pack will drop.

Cheers
DD

 

By the way, have you checked the bundle of ground wires at the rear of the water rail? Very important!

Cheers
DD

 

I don't think you need to be.



Then it can only be a wiring fault.

Remember there are TWO white/yellow wires and TWO white/yellow wire posts at the starter relay. One from the ignition switch to the starter relay and the other from the starter relay to the diode pack.




Easy test. There are 3 diodes in the red diode pack

1) when cranking the starter does the fuel pump work? If "yes" then that diode is OK

2) with the key "on" does the fuel pump operate when you use your fingers to push open the air flap in the air flow meter? If "yes", then that diode is OK

3) do you have 12v at the two brown/slate wires at the injector resistor/ballast pack? If "yes", then that diode is OK. You've already said that you DO have voltage to the injector pack so we alrady know the answer to that one







See my earlier post about checking for voltage at the injectors.




Right, they don't. The regular injectors are controlled by the ECU. The cold start injector is controlled by the thermotime switch.

The regular injectors get voltage from the injector ballast pack. The cold start injector gets voltage from the starter relay



Have you seen TWO white/yellow wires at the starter relay, as described in my earlier post?Each has it's own post on the starter relay....but the two posts are actually joined together


Best way is with a "noid" light:
OTC 7188 Bosch PFI Noid Light: Garden Center : Walmart.com
Lots of autoparts stores have 'em...sometimes for as little as $6-$7.

Cheers
DD

 

ok when I checked the white/yellow wire before it had power at the post that goes to the diode. I did not check the other white/yellow wire.
I checked both today and now there is no power at either white/yellow wire............im going right now to get a noid light. ill post the results later

 

ok i just realized when I checked for power at start relay only with the key on not cracking ill do it now cranked forget my last post

 

dumb question but do you have plenty gasoline in the tanks???

 

but yes fresh