Edited previous post . With no pre charge it points to pump control wiring before ECU replacement . Relay swap that you tried my have to be looked at again with a known good ( ? ) relay . Did you check the king relay on the trunk fuse box ? The print shows the second pump doesn't come on until a certain engine speed is reached .

 

There's the 5 relays in the trunk. The four in line and the one stand alone next to a row of fuses.

I swapped them all around as they are all blue 4 pin relays. The one in line with the fuses clicks when reinstalled, so that's good. Have put it in place for fuel pump and several others. No change. Believe the fuel pump is the purple plug, either way when testing I found the right plug, jumpered the terminals the relays usually would and got the fuel pump running that way. There's also the secondary pump relay back behind the battery, jumped that too, also got the pump running.

 

Fuel pump relay # 1 is the second one from far right ( passenger side ) . The previous owner of my car had the fuel pump wired through the auxiliary relay and it worked fine until the repair splice failed . Control circuit failed at RS3 corrosion was the reason they modified it with the Aux relay . Got it back to factory wiring configuration and works as original design . It's an option . A relay can click but still have bad power side contacts that show voltage but can't carry current load for a device .

 

that's right. It's in working order

 

Edited previous post

 

So i had a few minutes today.

Looked through all the relays. Tested them all with a DVOM. all work. all are good. Both underhood and trunk relays.

ECU is powering up as it's running other things fine like electric pump that flows coolant when key is turned to ON.

Double checked the wiring on the CKPS. Replaced CKPS with know good one off my 4.0 sport. No change. Checked functionality of new CKPS in 4.0 sport, works a treat. Not the problem.

Sprayed some brake cleaner in the airbox. After cranking a few seconds there was a bit of life. With a helper I'm sure it would come close to having it running on brake clean/ether. It has spark.

This time I decided to pinch off the fuel return line instead of feed. Still had to hotwire pump. All fuses and relays are fine, damn pump just isn't being told to do anything.

It ran, very very poorly, not on all six cilinders, but it ran, and died, I tried a few more times and got varying results. Can't touch the throttle, won't do more than idle like a pig. Did jump up to 2k rpm sort of for a second and died again.

Knowing this thing ran silky smooth and then suddenly not, I stopped the messing about.

Noticable was the clouds of very very white smokey exhuast. Much more burning oil like than coolant, it's still hanging about the workshop, I've had to leave it to air out. Could be flooded and old gasoline. Could be oil. I'll pull the plugs and inspect them. Last time I worked on this car six months ago I got this far I just remembered, pulled the plugs and can't remember what they looked like. Cleaned them then though so should be able to read them and see what it was burning this time around.

The fuel is at least 8 months old now. Though I don't suspect it's the main issue.

Still no fuel pump direction from either the ECU or I'm missing something very simple.

As far as the RS3 and P1 plugs go I can't find them, from what I can see I'd have to take the front wing off or gain acces by removing the bottom plastic shielding. There are too plugs forward of the washer bottle neck just behind the headlights, are they them?

In conclusion it's more than definately a fueling issue. I think the injectors aren't being pulsed and when I pinch of the return line the fuel pressure gets so high it forces them open and fuel dribbles in...

All injectors have 12v+ btw.

cheers

 

The RS3 connector can be accessed through the cabin just forward of the ECU and the PI1 and PI61 connector are both about 16 pin connectors . With respect to the time invested you may want to go with the auxiliary relay option then go back to the original wiring later so you can get going on the manual transmission .

 

All connecgors work. No break in wiring.

still no piwer to the fuel pump or its relay. Still no fire condition.

put fresh plugs in. No difference.

at my wits end on this one.

cranks and cranks but no sign of life.

H E L P!?

 

Left field thought, but you are sure you dont have water in the fuel tank?
It sinks to the bottom of any petrol, so goes straight to the head of the queue for ingestion into the engine
Your comment about firing on brake cleaner, and white smoke when you hotwired the pumps set me thinking...

 

You can hot wire with a common blade connector ( not paperclip) the pump through the relay's power output socket by removing the relay and putting B+ on the forward most socket . Red/ Yellow wire color . This goes straight to the pump . High current arcing hazard so make the final hot wire connection other then the socket .

It would be a good feeling to hear the engine running .

 

Hotwiring the pump only does so much still have to pinch off the return to get it to run barely. Not driveable. It drove and ran perfectly. I need to figure out why it isnt being triggered as i suspect the injectors and pump arent either.

i want to put this motor in my 78 xj6 with a 5 spd i have for it but i wont remove it b4 it runs again. As a transplant troubleshooting will be even worse. It ran fine, key off. Then started with this nonsense.

to recap;

all fuses good.
inertia switch good.
all relays swapped a billion times all working
no wiring issues.
fuel pumps both work when hotwired
new plugs
coils good
J gate good

turn ignition on everything lights up. Check engine stays on. Cranks and cranks not a hint of life and fuel pump has nit received any signal or done a thing

other ecu functions like starting coolamt circulation for water to air work fine.

ckos reeds 200rpm when cranking.

could i have the wrong key?! Correct fobs... bit i have a few of these jags as parts cars. How does the key to ecu relationship work?






I am beyond frustrated.

anyone know who does ecu programming on these so i can have the security removed amd double check the key isnt messed up.chip wise or something.

 

If your pinching off the return to get something have you looked at the fuel pressure regulator fully bypassing ? As Countyjag suggested bad fuel may need to be replaced . The X300 does not have a anti siphon fuel pipe if I remember correctly . If the car sat for a while piston rings can be bypassing to not get good enough compression . They can be loosend up from the top of the piston .

 

No

Primarily because the issue is prior to this. If the fuel pump isn't being triggered and perhaps and most likely neither are the injectors, there is no point in looking at the FPR.

First things first. Why is my blasted ECU not triggering my fuel pump and injectors?

That's what I need to figure out first...

 

ECU connector condition OK as well as the CKPS connector . Although it is a pulsed signal you can still read a fundamental resistance through the sensor and by jumping the sensor reading just the wires . I'll read mine now for values .

Black 23 to Black 26 Check sockets for pinch

Fuel pump enable is Black 19

Shield ground PIG153L located on upper left firewall

 

Have you taken the ECU out and checked that there is no visual damage to it? Just because it is firing other things like the aux water pump is not an indication that it is not deficient in the FP circuit. If you have a jag wrecker nearby it might be worth while approaching them to see if they have a compatible ECU you could borrow?

 

1390 ohms through KSPS and 0.6 through paper clip

0.9 ohms from ECU to the fuel pump relay , verified pin 7 at the Papa Indy 61 connector

Papa Indy 61 is the black one 1 is the white one , one would say . The Pink/Brown wire is at the blue arrow .

Be careful not to break the locking arm post on the RS3 connector and no wing or plastic well removal by going through cabin

 

Vehicles outside USA have a transponder chip in the key. If the key is not identified during the ignition on sequence fuel injection is inhibited although cranking is enabled. The key chip is read by a transponder ring fitted around the ignition switch and is compared with the registered keys programmed in the security and locking control module (SLCM) in the trunk. If the key matches the SLCM then communicates with the ECU using encoded signals and injection is enabled. As far as I know registering keys with the SLCM requires dealer level software. I suppose it may be possible to modify the ECU to allow injection if the "key accepted" signal is not present - after all USA versions do not have this additional security. I have seen posts asking if anyone knows how to bypass or remove the key security check but I do not know of anyone who has been able to do so. The communication between the SLCM and the ECU is an encoded data stream and not just a simple single line on/off.

 

im starting to wonder if my problem isnt somewhere in this realm. I'll keep plodding along. Ive dealt with the GM PATS system in the past and built a bypass for it. But thats simple stuff. Anyone in the US have an xjr6 ecu?

thanks for all the work Lady Penelope I'll get tot that today and go through it all. Cheers

 

You are a wealth of knowledge and I just want to say to everyone I appreciate your help and you especially as you are going to trouble to help a stranger. Cheers.

When I replaced the CKPS I Ohm tested the old and new. Thanks though. BTW, where is Fuel pump enable Black 19? Pin 19 on the black plug of the ECU? It's a ground signal I presume?

Made a little progress today and perhaps I could be eating my words, slightly on the FPR in any case. Had a helper today, extra pair of hands works wonders.

Here's what I learned today:

- Injector pulse is present. Not the problem.

- TPS is fine (someone suggested ECU reading WOT disabling fueling). Hooked OBD reader and TPS voltage is in line with the pedal action.

- It can run smoothly on brake cleaner. (which would rule out compression/timing/ECU and all other issues besides fuel delivery)

So it has to be FPR, bad fuel or bad fuel pump. I haven't tested fuel pressure yet...


Here's how I reached the above:

So, got my helper to crank the engine over, I had removed the air cleaner and had gotten a bit of life in the past with brake cleaner as fuel but not much. that was on my own at an awkward angle. Now able to look right at the MAF screen I was able to liberally and carefully dose the brake clean while my helper cranked the engine.

Presto. It came to life and I could keep a buttery smooth steady idle by pulsing my brake clean input. It was great to hear it run again! We tried to match extra throttle and extra "fuel" and it picked up pretty smoothly.

So that's a relief on some fronts, creates more questions on others. I guess most important is, what's next:

Replace FPR. Drain fuel, refil with good fuel. Check fuel pressure. Once that is all done and I have good fuel and good fuel pressure I can't see any reason why a hotwired fuel pump shouldn't run the engine. Then the next step will be figuring out why the pump isn't kicking on.

Something else I noticed again today that I'd forgotten is that the fuel rail and/or FPR make a REALLY loud hissing sound when the fuel pump is running, an abnormal sound if you ask me. It goes away when I pinch off the return line... My x300 4.0 sport doesn't make that noise.

Seems like I have multiple issues on my hands that just happen to coincide and be fuel delivery related. Thoughts?

cheers.

 

Vroom , Vroom... ...............Vroom . FPR will hiss up to a point before bypassing to much as the pinching proves . If you tap in a pressure gauge it should regulate at about 43 PSI at idle and bumps up with throttle with the vacuum line on the back of the FPR ( is it off ? ) . They don't last forever anyway . Mine is OK and was able to return it after troubleshooting . Make sure you use 2 wrenches on the fuel lines for they do twist or crack the lines .

On the Black 19 on the car side of the ECU connector it is a ground through the ECU as most if not all ECU enables are a ground and not a power source . You can tap that wire to ground outside the ECU to hotwire going through to Papa Indy 61 and the RS3 connectors . The fuse that gives power to the pulling coil of the # 1 fuel pump relay is in the RH Healboard ( back seat ) fuse box # 10 / 5 amp as the relay control is ground seeking through the ECU .

Brake cleaner as a fuel could be compensating for a weakness somewhere else , But it may ruin you Mass Air Flow Meter so put your money on a FPR before you have the buy a AFM and calibration as I believe it is not plug and play . You can drill a whole in the AFM body aft of the chemical sensitive sensor for the red nozzle tube but the whole will throw off the accuracy of the AFM reading . Plug it up with tape as you troubleshoot and glue later .

Since you have a # 2 fuel pump for the SC engine you can compensate for a weak # 1 by hotwiring the # 2 . As designed it does not turn on until 4000 RPM and doesn't turn off until it falls through 4000 then off at 3200 . It does this by the same CKPS and the ECU . See editing diagram for hotwire details .