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Watching the voltmeter that is very accurate you have a expected voltage sag to X , hard to see so let me expand the video size to see it better
9 ? which is too low , 9 would not be bad starter solenoid relay power contacts related but good relay power contacts
You also have a good solenoid itself as the extension ( somewhat ) and the battery cable power contacts inside the solenoid to account for the voltage sag
the large clunking is the starter solenoid expanding the starter motor gear into the starter ring
This means you have all the agreements for starter engagement, so you are past that point
Some things you can try is to swap the starter solenoid relay as it may have burnt power contacts , agian 9 volt meter reading says it's OK
This relay is the same for the headlights , fog , A/ C clutch
Battery good ?
Never install battery in backwards and never over tighten the battery positive post bolt
So you have a battery cable current / power " supply " issue
Take a look down through the intake pipes for the starter solenoid top terminal post nut for being loose heavy battery cable , 13 mm socket , 3 inch extension from under the car but maybe from top ? Check the large starter ground strap from the starter mound bolt to the chassis ground , 10 mm while there , this definitely from under car , the large starter voltage sag says the large ground strap is good
B1mcp ( Brendan McPhillips ) had a good pic of this
There is a large battery cable ( starter cable ) terminal post on the right wheel well sheet metal inside the engine bay about 4 inches from the rear engine firewall that can give problems , remove battery cable and wiggle post , this is point ST3 on the top red line in the diagram pic
This starter cable goes both ways as the starter umf from the battery and in reverse to go between the alternator and the rest of the car ( battery charging and fuse boxes to power systems )
You have 2 more terminal post to the battery as the umf goes fwd , one easy and one hard before starter removal
Right at the battery positive post as it turns down ( point ST8 )
And under the rear seat pan as you remove whole seat pan under a black triangle cover ( point ST6 )
Battery positive post shims ? clamp stretches over time , put some battery terminal red oil under cap to a clean terminal post
Thanks for all that info. When I took the video the car was being jumped by another car (had to do the old engine jump truck to open trunk routine) so it wasn't under its own power. I've had the battery on a tender all day since and still have no power. So could it be as simple as the battery is bad so it won't start?
First thing is take to a common auto parts store to load test , but is a Sunday afternoon , this test takes a hour at the / on their store equipment time
A tender will take forever to recharge , the 13 volts on the gauge was the jumper cart
But keep it charging overnight to be best before auto parts store test time , but it may just start
MAY HAVE A PARISITIC BATTERY DRAIN TO LOOK AT AS A 2nd SUBJECT and new thread
First thing is take to a common auto parts store to load test , but is a Sunday afternoon , this test takes a hour at the / on their store equipment time
A tender will take forever to recharge , the 13 volts on the gauge was the jumper cart
But keep it charging overnight to be best before auto parts store test time , but it may just start
MAY HAVE A PARISITIC BATTERY DRAIN TO LOOK AT AS A 2nd SUBJECT and new thread
Jumper cables positive cable car fwd post ?
Sounds good, thanks again! I've been trying to decipher what battery the car should take as well. The big box auto stores are recommending group 45 battery's but to my knowledge I thought the Vanden plas was suppose to have group 49? Any insights on this in case I need a replacement?
As well as all the good info from Parker another battery lead connection to check is where the cable passes through the firewall. It will be in the RHS front footwell close to the transmission tunnel. It is a brass stud, threaded on both ends and it passes through a plastic insulator and because of where it is it is impossible tighten without the help of an assistant.
All the battery lead connectors, from the battery to the alternator, in my car were loose when I bought it and cleaning and tightening them all solved a battery charging problem I had.
Because of all the issues I had with my XK8 and the codes that came in when the battery went totally dead, I keep the batteries on my XK8 and X300 on a battery tender all the time. On the XK8, if it goes too low, you will start seeing some really crazy codes in reference to all kinds of communication bus issues. Until you clear them out, charge the battery you will think that all hell broke loose.
" On " lower right firewall plain area terminal post / through as it continues inside right fender quarter panel up to the inside engine compartment right wheel well sheet metal terminal post ( 4 inches fwd of rear firewall plain ) . Thanks
That is one thing I was not aware of ( your detailed work ) in my long going and current starting issues and will look into at the through firewall terminal post and get pics of it
My car was wrecked on the right and replaced right front quarter panel by the previous owner
So it makes sense
The right lower footwell 48 wire RS3 engine regulation connector was damaged , and they did a half ars job of salvaging the original connector ( tie wraps together ) which led them to abandoning the car to me with 110 K miles , with I'm sure many reliability issues hence low miles for me to enjoy , one being the fuel pump relay command close wire that surprisingly goes through RS3
I did bring a long very heavy thicker than the original gauge # battery ( professionally made at a battery cable shop ) cable around the outside of the car from the rear seat terminal you made me aware of to the terminal post on the right engine bay wheel well terminal post ( ST3 ) but my work at that time may have been lacking
Car does run if starter rotation
Last edited by Parker 7; Sep 10, 2024 at 06:58 PM.
Second Video only a couple minutes after first, now showing some oil pressure but still not turning over... maybe its not getting any spark? Should I check and replace spark plugs/ coils? https://drive.google.com/file/d/1onh...ew?usp=sharing
# 9 small relay in the corner of the right engine bay fuse box ( this fuse box has fuse X ) that closes the starter solenoid relay and powers the ECU with fuse A
The starter solenoid relay control fuse is X , the muscle power through the starter solenoid relay is fuse Y ( hot at all times from the left engine bay fuse box )
# 5 large ECU controlled relay that brings power back into the ECU , half of your engine sensors , and powers the fuel injectors to open
Fuse B and C for the # 5 large ECU control relay
Place your finger in these 2 relays and feel for click with key in run position , you can do this yourself by removing the relay
To get the # 5 large relay to close the # 9 small must close first as the ECU low power section controls the # 5 large for ECU high power section
You have cheap relay swapping options , left engine bay fuse box as this relay only controls the car horn , and headlights , fog , A/C clutch for the large
There is a fuse that controls the fuel pump relay as fuse Z and that fuse requires the right heelboard fuse box relay in the corner to close
same click test as before
The common denominator is the ignition switch and it's ground path through pin 5 ( no need for a new ignition switch just yet ) you can change this switch if needed and no new key or key barrel
I'll get you X , Y , and Z later but the emphasis here is on a intermittent or hard fail relay closing
Last edited by Parker 7; Sep 12, 2024 at 09:00 AM.
The explanation for the codes you are being given by the app is wrong.
They are to do with the O2 sensors and I won't worry about them till the engine starts.
See here https://forums.jag-lovers.com/t/x300...5-codes/237061
Have you tried the easy option of replacing the crank position sensor? This is not too expensive, and if its not failed this time, it will soon so you have nothing to loose by swapping it now!
Yes , he has no tach on starter rotation , but the engine should fire off with the CMPS and then revert to CKPS
But the CMPS would not feed the tach gauge
Hey Parker. I don't think that is correct. AFAIK the ECU only ever uses the CKPS for spark and injector firing. The CMPS is only used at startup to determine (in conjunction with CKPS) whether No. 1 cylinder is at TDC for Firing stroke or Exhaust stroke. The actual fire trigger comes from the timed CKPS.
The CMPS is not timed to the degree that the CKPS is so cannot be used for precise fire triggers for spark and injector. The CMPS has to be only in the right ball park for No. 1 TDC for it to work OK.
So I would agree with @Cafcpete that if there is no tach movement on cranking then a new CKPS would be first step.
I don't see the evidence of no Tach movement - only in the first vid where battery was dead.
The engine sounds like it's turning over too fast to me. That's usually a sign of low/no compression. I think a compression test would be in order - could be a Bore Wash problem.
Would be interesting to know what happened immediately before it was parked up for a few months - was it started and moved a short distance and then turned off? That's a classic scenario for enducing Bore Wash.
For a bore wash condition in a light case , you can crank the engine with the gas pedal to the floor and then release for start
The ECU knows to cut the fuel in this setup ( low MAF and such ) and has a chance to recoat the cylinders with compression sealing oil from under the piston
In hard examples you would remove the plugs and put a bit of oil on top of each cylinder , crank trough a few turns and let soak ( overnight ? )
I read where they use a gun oil to get it to creep into say piston rings ?
It will smoke , smoke a lot on engine startup but is the smell of victory
Last edited by Parker 7; Sep 12, 2024 at 07:22 PM.
Ok so to answer a question, The car was drove about once a week around town and from one freeway exit to another just to keep it going. But after I parked it at my mothers, that stopped happening. So when it was parked the only code I knew of was the one for the exhaust/CAT not being there. Over that year the battery obv went bad but thats the extent that I know of. I took a new video with the whole dash visible at crank. It seems as if the tac is moving. So a place to start looking would be great. If it's too much for me to do on my own I have a good mechanic that I suppose I could take it to down the road but trying to avoid that (but with me being a novice it may just come to that)
I see tach is moving and is a good reading ( but a little low ) for starter rotation
Place finger on the fuel pump relay and feel for click on initial key rotation
The fuel pump will run for 3 seconds only then off
With a good ear you can hear the pump
The fuel pump relay clicks back on when the CKPS sees engine rotation above a certain point , safety design
The initial 3 second fuel " charging " of the fuel lines will be trapped in the lines until the 2nd pump turn on catches it
Fuel line charging is different than cylinder priming
With the 3 second fuel charging you should get at least a couple of combustions
You may have to cycle the key several times to build up fuel pressure if that charging is leaking off , injectors normal feed and stuck open , fuel pressure regulator leaking past the rubber diaphragm and a check valve inside the fuel pump itself
You can pull the vacuum hose off the FPR and ensure it is not wet
Bad tank of gas as this model is sensitive
Main fuel filter change ?
You can jumper the fuel pump relay to power the fuel pump at all times between socket 3 and 5
This will eventually drain the battery with the keys in your pocket
2 fuses for the fuel pump relay ? and that right heelboard fuse box king relay clicking closed ?
The # 2 fuel pump is for supercharged or V - 12 models
Last edited by Parker 7; Sep 13, 2024 at 09:09 AM.
As well as all the good info from Parker another battery lead connection to check is where the cable passes through the firewall. It will be in the RHS front footwell close to the transmission tunnel. It is a brass stud, threaded on both ends and it passes through a plastic insulator and because of where it is it is impossible tighten without the help of an assistant.
All the battery lead connectors, from the battery to the alternator, in my car were loose when I bought it and cleaning and tightening them all solved a battery charging problem I had.
Cheers,
Jeff.
Hello. Im just going to jump in here to reply to this ansewer. Great info! I had the exact problems as the OP in this thread. You said about the firewall, and i decided to check it in my car, and Jesus! I found a fire hazard. I recommend everyone else checking that place out too even though, your car may not have these symptoms. You can even see the lighting marks in the metal, and the burned foam around the cable.
-Ozzo
When I checked mine the insulator was partially melted indicating a loose connection and high resistance causing it to heat up. Lucky it didn’t short out on the firewall metal and blow the fuse or worse set the car on fire.