So what your saying is it should be fine once i put both of the new pumps in place? Or should i go ahead and replace the relays?

 

Since you already have the pumps out you might as well replace them and go forward . They don't last forever and there not that expensive . Do replace the relays and you will have the things that are electromechanicaly dependent on each other covered . After you have done that we will go through the control circuit of the relays that contacts the power circuit to drive the pumps . I have experience on both control and power circuits of this system . On the print I made above you will see the position of the # 2 pump relay

Any questions , just ask

 

In theory it should fire right up if you've renewed the pumps and their filters, relays and have fresh gas a good battery and looked after the bores with a bit of oil.
Hopefully you read this and it's running happily.

 

did some more testing, There is no power coming to relay number 4, therefor nothing also to fuse 7. so i need to know where relay Number 4 Feeds from? that way i can see why it is not getting power. i ordered pumps and spark plugs and all other tuneup items.

 

Here's a couple things to put in your Jag ammunition bag....
Save this one to your favorites, JagRepair.com - Jaguar Repair Information Resource ...I already have it at the electrical guide, prompt the first result.
Here, link 2 tells where to get the Workshop Manual.... https://www.jaguarforums.com/forum/x...al-pdf-183893/
The PDF below may help also...

 

The feed is momentary on ignition to prime/build fuel pressure via the ECM. Check the feed when turning ignition on.

By the way, just remembered - I had a no start on my 100 that turned out to be a bad connection on the engine temp sensor, cleaned up the connections, (flooded with wd40 and a few off/on connections) it fired first time - this after sitting all winter last year - another item to check, as this inhibits engine start if coolant temp signal is lost.

 

Alright guys soooo, got my airtex pumps and I installed them, in the time ive been waiting for my pumps the car actually stopped cranking. the battery is fine, when i try to start it all i hear is a loud click. I have a feeling i burned out the starter while cranking it over and over last week while the pumps were dead.

 

Go back and download the PDF in post #25. Check the connections at the starter and what condition are your battery cables? Any corrosion can prevent proper voltage distribution, replace the cable. Be sure to check your grounding points also.

 

Swap out the starter relay and a good battery charge of 12.77 volts , you are getting the commanded signal for it to engage , just wont motate . Starter motors do have a duty cycle that nobody thinks about in the heat of battle . There is a starter rebuild kit on Ebay from England if it comes to that . I Never used one .

You can have the battery load tested for free at the auto part store

 

I have brought a dozen or so 308s back from the dead and what you are describing is usually one of two things, the key or the battery, but usually the key. I did have one with a battery so fried that even on my huge 200a box she wouldn't crank.

 

Sorry, didn't read far enough down

 

If you need to go through the key switch we can do that if it comes to that , been there . X300 and X308 are exactly the same part # and circuit .

 

Alright guys,

1. How could it be the key if just a few days ago it was cranking just fine? nothing has changed since then.
To describe it is i turn the key to crank and its just one loud CLICK sound and thats it

2. as for it being the battery it is holding just fine at 12. And I put jumper cables on it from a running car and tried to crank it that way too and same exact click sound. so I would rule out the battery at that point.

I have had many bmws and mercedes and cant remember a single time that a relay has gone out, is it actually that common in JAG for a relay to be the cause of something? i have 1 brand new relay for it and i think all the relays are the same so ill test that.

 

The loud click ( of the starter and the relay both ) verifies you have a correct commanded signal by way of the key switch . Now it is the amount of power we are concerned with by insuring you have a good power contact inside the relay by swapping and ensuring a fully charged battery . The last thing would be to remove the starter . Someone once had a loose starter terminal post on the engine firewall and was easy to tighten up and is your engine ground strap clean and secure ?

Someone mentioned Jaguar's don't take too well with jump starting and this I don't understand . Can someone explain ?

Not to get picky with how accurate the battery voltage reading is but a 12.0 reading is a 50 % charge .

 

Me.
Jump starts are bad for the car if you leave the ignition on and hook up, I left my car in the paintshop and it required a jump start to move it multiple fuses blown on the left and right heel boards - steering column control, front seats etc, lots of stuff dead. I kind of held my temper with the guy who did it...

+1 on 12V it needs to be a battery in good order or new to run the systems on these cars - it needs over 12.5V minimum, even then you'll get TRAC/STAB/ABS warnings flashing on cranking. The click is the starter relay on the front left hand inner wing panel bracket, either you've a dying battery and it's trying to start, a bad earth. No to burnt out starter, no to bad relay. Plain and simple from me at this point

 

Battery is giving off 12.6V, checked the relay and replaced it and same result, can somone point me to where the starter is? i have looked for a picture of where it sits and cannot find it, i just want to see if knocking on it a little will get it to do something.

 

No pics but this may help :

https://www.jaguarforums.com/forum/x...r-motor-76686/

and

https://www.jaguarforums.com/forum/x...ast-way-77394/

 

Alright guys here we go, CHecked fuel pressure at the rain and now i have it since i replaced the pumps, I found the starter and knocked on it while cranking and it cranked now but the battery was super weak, but at least now i know it was the starter causing that click, soooooooo i need a starter and a battery. I am about to order a desno starter, What battery do i get and from where please. i believe we are getting close i can feel it.

 

Any correct size battery will work. Instead of a replacement starter, find your local alternator and starter rebuild guy and take it there. For less, they will rebuild it and have you on the road in minutes.

 

local shop wants $100 to repair it, not sure if its worth the savings considering a desno one is like $170 new in the box.