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Okay, here we go. TLR -> not getting fuel to rail, crank no start, other things
Still learning the etiquette here so I am open to any critique. Feel free to move my thread or direct me to a good thread with answers. My issue is a good crank, but no start on my 1996 XJ6 X300. Some background info is:
It sat for a few years, then was driven a couple times before sitting for about 1.5 more years. Got the car from someone who didn't want to work on it, they got it for free so just drove it a few times and didn't want to mess with it when it no longer started. They didn't have any knowledge on it.
I trailered it home and did an oil change, didn't change filter, oil light still on. Got a new battery from autozone for year, make, model, put it in and all electronics seem to work, and all lights on dash come on, but battery light stays on whole time. I put in 1/2 tank of new fuel (mixed with some sea foam and probably a gallon (3.78 liters) of old (a year old possibly older) fuel that was still in the tank.
I started with the usual suggestions of check list of diagnostics
It has check engine light (that stays on the whole time) on so ran a bluetooth scanner and then another code scanner and got no codes. Hit the inertia switch anyways, and its a US car, so probably no immobilizer. Battery voltage is good at rest (12.6). when cranking it is hovering around 11 volts as per the reading on the multimeter, but its not getting to 11.5. I'm not sure if this is an issue causing the ECM to not do its job, as I heard it may need 11.5 (if thats the case, whats a better battery? Or is this maybe a wiring problem?). Checked all fuses and checked all relays that relate to fuel, starter, ecm. Tested relays with multimeter and ground and power to hear a click. All seem good. I have cleaned and actually replaced the crank shaft position sensor because it is barely moving while cranking, it just wiggles barely at the zero line and is not getting to 200 rpm. The RPM needle actually does the same with CKPS disconnected. Am planning to check to see if there's resistance between CKPS and ECM. However, the main issue so far i can see is no fuel delivery to fuel rail. With help I did try starter fluid sprayed in air intake bypassing the MAF, and it for a split second sounded different, my helper said the same, and I saw a faint cloud blue exhaust come out of back. I have been looking into fuel pump. Fuel fuse, relay, all good.
Now my question. I provide power to the fuel pump relay and hear a sloshing sound in the tank, like water pouring, but still no fuel to rail. I only jumped it about 30 seconds. The sound is very quiet and definitely not a whirring sound. Almost as if the fuel pump is pumping fuel back into the tank. Is it possible the pipe inside the tank is disconnected? Or is that the return line bring fuel back in? Should I open up the tank from the back seat and have a look?
I plan to test spark plugs once I can get fuel to the rail. I also have a new fuel filter and will check the state of the old one as im guessing it could be clogging the fuel line.
Thanks
For the XJS, and the x300 is similar, but not always the same, there are a bunch of small hoses inside the tank that would be at the age where they have disintegrated rendering a working fuel pump useless. I don't think they had planned on being submerged for 30 years without fuel pump replacement.
If you have access through the back, which the XJS does not have, then take a look! If what you hear is correct, that may very well be your problem!
If you do have enough access to replace these hoses, use Gates Barricade hoses, which is sold by the inch for what you would expect to pay by the foot. Also, might as well replace the fuel pump too, while you're there.
" Now my question. I provide power to the fuel pump relay and hear a sloshing sound in the tank, like water pouring, but still no fuel to rail. I only jumped it about 30 seconds. The sound is very quiet and definitely not a whirring sound. Almost as if the fuel pump is pumping fuel back into the tank. Is it possible the pipe inside the tank is disconnected? Or is that the return line bring fuel back in? Should I open up the tank from the back seat and have a look? "
In removing the back seat the rear vertical wall and bottom pan will give you nothing as tank access
The sound you hear is the complete circuit from the tank to the fuel pressure regulator at the fuel rail and the excess pressure bypassing in the FPR tp go back into the tank , you might place your finger on the FPR and feel it vibrate
In the normal starting seguence the pump will run for 3 seconds only then off, It will come back on when the ECU sees engine rotation
This 3 second fuel " charge " different then fuel prime must be trapped in the fuel rail by a check valve in the pump ( some have placed a check valve outside the tank ) , the FPR , and the injectors
The fuel pump has a secret control fuse other than the power fuse in the trunk, if your fuel pump relay does click with your finger on it the secret fuse is good
# 10 / 5 amp right heelboard fuse box , this fuse requires the relay in the corner of the fuse box to close , to test have the key in the run position and on relay removal it should click back open in your fingers
The inertia switch can fail to reset by pressing the button and you can remove the connector and jump with a paper clip between the 2 white wires
No immobilizer chip in key for US models
The fuel injectors will not open until the ECU Controled relay closes , there is a relay control fuse and power through fuse
# 6 / 5 amp right engine bay fuse box for control # 11 / 20 amp right engine bay fuse box for power
This is large relay # 5 right , you can swap this relay part # 6707 with a headlight , fog , or A / C clutch of the same part #
Pic coming
The CKPS will read 1300 ohms as a basic meter reading . you can read this at the ECU connector as socket Black 23 and Black 26
To power the CKPS " resolution " inside the ECU ( tach comes from ECU ) , the ECU needs first power as the right engine bay fuse box relay clicking closed with key rotation and fuse # 12 , there is the Papa Indy 1 connector in between
White / Pink wire position 4
The second power to the ECU is the large # 5 right ECU Controlled relay again
Yes on main fuel filter change and get rid of old fuel , there are O - rings down inside the fuel filter fitting , arrow on filter to the outside direction.
Your gurgle in the tank again could be that you already have good fuel pressure coming back from the FPR ( in start sequence )
The FPR can fail to the low side as they don't last forever ( rubber diaphragm ) $ 90 US , regulated fuel pressure 43 PSI
" I can see is no fuel delivery to fuel rail " How do you see this ?
Thanks Parker 7, pictures really helping
I had disconnected the fuel line where it meets with fuel rail, supplying power to the pump gave me no fuel coming out of the fuel line. I looked inside the fuel tank, it was very rusty but the hose/pipe was connected well. So the sound must be the fuel pressure regulator you mentioned. Changing the fuel filter today to see what that will do.
CKPS - when unplugging the CKPS and testing resistance between its wire connector and Papa Indy 1, I am getting some resistance (I think around 400-500). Is this normal? Or should there be 0 resistance between CKPS and Papa Indy 1?
Thanks for your reply again parker
New fuel filter installed and with jumping the fuel pump relay, still no fuel delivery to engine. This is leading me to believe a new fuel pump is needed. The fuel relay clicks still but I hear no sound other than what was previously talked about.
CKPS - What about the resistance between ckps connector and ecu pins? should there be any resistance in that whole wiring path? I am getting some, which leads me to believe this is the cause of such little rpm reading (zero)
" CKPS - What about the resistance between ckps connector and ecu pins? should there be any resistance in that whole wiring path? I am getting some, which leads me to believe this is the cause of such little rpm reading (zero) "
There should be little if no resistance from the ECU connector to the CKPS pigtail connector on the White and Orange wire , straight wires , Black 23 and Black 26
Pic coming for the SC engine that is very the same , extra fuel pump
As the fuel pump fails it will sometimes burn the power contact inside the fuel pump relay ( bypassed ) and the connector sockets on the pump motor
The pump motor connector is on top of the tank behind the fwd trunk wall liner , you will see the connector for a 2nd pump
If the car has been sitting the pump can be stuck and you can jumper the relay sockets with a battery charger ( slightly higher voltage / electromotive force ) to free up a stuck pump
The fuel test point is the rear of the fuel rail ?
I have jumped the fuel relay with a jumper wire coming from the battery, it is not getting unstuck as you mentioned may work. The fuel test point is the rear of the fuel rail ? - is this just a screw off cap or something that I test with a pressure gage? or is it just disconnecting the fuel line somewhere around the fuel regulator. I was testing for fuel pressure by taking off the fuel line where it connects to the fuel rail near the windscreen.
As for ECU not getting signal from CKPS, I am still working on this..
Well I pulled out the fuel pump and saw the electrical wire contacts were very gummed up and soldered up and the whole pump itself was horrible. Would have tested it but cant even see the contacts on the pump side. A new pump on the way and will have to get to cleaning the fuel tank before anything else. I am also having to rewire the CKPS to the ECU.
The wires don't go from CKPS straight to ECU as the manual shows? (through some connectors of course) I am thinking of running the wires from the CKPS all the way to the ecu and spicing them into their spots (23 and 26). Would this not work? I wanted to do this becasue I was finding no connection between ecu pins and CKPS
Double check the wire colors , Black 23 / White , Black 26 / Orange
The wires come through the rear engine firewall after going over the fuel rail as a bundle , there is a through grommet to the cars right slightly off center
The wires are too sensitive to use a butt splice and needs to be water proof as I recall you have a water ingression to the ECU connector
Are you looking at the CKPS on the crankshaft front and not the CMPS above on the engine block left side ( hockey puck ) ?
Update: Still waiting on a new fuel pump in the mail. In the mean time I have been cleaning the fuel tank out as it was gross and rusty. Disposed of old fuel.
While waiting for a new fuel pump I put in new wires from the CKPS to the wires of the ECU 23 and 26. I used wire splicers on one end and butt connectors on the other end. I ran 16 awg wire. However I am still getting no tach when cranking. I'm also getting no spark. Was running 16 awg a horrible idea?
" However I am still getting no tach when cranking. I'm also getting no spark. "
The relay check on the small one in the corner of the right engine bay fuse box ( and fuse 10 , 12 , 14 , 16 ) and the large one as the # 5 right ( there are 2 fuses # 6 and 11 right engine bay fuse box )
The large # 5 right relay may have been swapped mounting positions
Even though they may click on your finger tip as you feel ( must feel and not listen ) when rotating the key ( verifies correct command ) the relays can still be compromised on the internal power contacts
The no spark , in the very beginning it should be looking at the Camshaft position sensor so we come back around to if the ECU is properly powered.
After the Crankshaft position sensor sees engine rotation it will pick up the duties of ignition and fuel injector timing
This after 1 crankshaft rotation and the CMPS has fired off 3 cylinders as it controls them ( it sees all 6 cylinders TDC fire positions as 6 individual windows )
On the 2nd crankshaft rotation, the 6 cylinders should have fired off and the CKPS transfer should have begun
The connector to the CMPS can be removed and the engine will still start , but more crankshaft rotations just using the CKPS