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Great. the noise was combustion. That means you have spark. So, you can concentrate on the failure to fuel issue.
Ether is more combustible than gas. Kerosene is less combustible than gas.
A squirt of gas can work... Primes the cylinder with fuel. A little dab will do ya. do not flood...
Great. the noise was combustion. That means you have spark. So, you can concentrate on the failure to fuel issue.
I apologize--I thought somewhere early on here I mentioned that I'd verified that there is spark. Regardless, the started fluid info is good to know, and thank you.
James, the drain hole that was mentioned is in the bodywork at the bottom of the recess towards the back of the car just below your pic of your filler cap. It is easy to miss. It does get plugged up with stuff and the water that would normally be expelled ends up in your tank. This was one of the problems that I had when dealing with a no start situation.
Con
Thank you! I would never have found that on my own. I looked all over and never saw it. I had to vacuum out bits of leaves and debris to see it.
I plugged the filler hole and poured some WD40 down it (I've got a big can of it and figured it wouldn't do any harm). Left side is okay, right side is constricted. What do you use to clean it? I used a long zip tie to go in to the top and bottom, but I think it's plugged or constricted somewhere deep inside.
I'm just curious -- if these get plugged, why would that cause a no-start?
With key in ON (pos 3), no voltage at the positive end of the coil. No voltage on either side or across the injector sockets. No voltage at the power resistor pack on any pin.
Checked ground from the coil to various places, including the battery terminal--got continuity (good ground).
Pulled and checked the resistor pack -- started another thread to show that. I believe it's working correctly (i.e. not blown or burned up).
Just for my own peace of mind, I shorted the inertial fuel cutoff switch to make sure that wasn't at fault somehow.
Only thing I can think of now is to swap the ECU. That would require a chunk of money and a trip to the wrecking yard (about 90-120 minutes away, each way). And that's provided the junkyard ECU is good.
James,
If you have good fuel pressure, ignition spark with fuel injectors not opening.... suggestions for process of elimination...
1. Look at diagram of fuel circuit, top left hand corner you see Ignition coil, the (WB) white and black wire on the negative terminal of the ignition coil is where the fuel injection computer gets its initial electrical input signal, if you have good circuit all the way to pin 1 on computer go to 2.
2. Look at lower right hand corner of diagram you will find power resistors, with key in position 3, you must have 12 volts to connector (at bottom of resister pack) at the two wires NS, if you have good voltage, then good to 3. Clean connect and input to PWR Resister with contact cleaner: installing and removing connector 3 or 4 times spraying cleaner each time.
3. With ign. key on position 3, you remove connector from each injector and check for voltage (less than 12 volts) on input wire OU, OW, O, OP, OY & OR on connectors; if you have voltage, then go to 4.
4. Replace 6 fuel injectors connectors, and with ign. key on position 3 check for voltage at connector to ECU computer (in trunk on wall behind rear seats); ON, OB, OLG, OG, OS, OK, should have voltage (less than 12). (Clean connect and input to ECU with contact cleaner: installing and removing connector 3 or 4 times spraying cleaner each time.
The computer takes the Ignition Coil signal at 1 and provides a ground for the fuel injectors the appropriate time at, 14, 15, 30, 31, 32, 33. The only check I know is substituting another computer, if you have good wiring to the ECU connectors. Historically the ECU is one of the most reliable units in the circuit...
Others have been down the path and may have short cuts as well as other tests. You may want to put a trickle charger on your battery overnight, just to insure you have good voltage for further testing.
You are making good progress and are becoming familiar with the hidden things that make Jaguars a Fun hobby.
Rgds
David
Last edited by David84XJ6; 07-18-2021 at 06:54 PM.
"So here's where I am now.
With key in ON (pos 3), no voltage at the positive end of the coil. No voltage on either side or across the injector sockets. No voltage at the power resistor pack on any pin."
James
I was writing post and didn't see your last post.... It does point to ignition switch or the wiring from Ignition switch to the main relay connector and the fuel pump relay..
Starting at top right hand corner of wiring diagram: follow Ignition Feed POS # 3 (WY wire) , Direct Battery Feed (N wire), and Ignition Feed Pos. #2 & #3 (W wire) to the relay sockets to insure you have voltage from Ignition switch. The W wire goes to fuel pump socket first Terminal 30) and to then to pin 1 on diode pack to ... out of pin 4 to pin 86 on main relay. (Check pin 85 on connector for ground connection)
Ignition switch is two part mechanical and electrical, you can change the electrical part (SNG has DAC1607); or you can look up threads on how to disassemble and clean the electrical portion of the ignition switch on this sight (many have done)
Rgds
David
I think it's the ignition switch. A few weeks ago it bound it up on me. I zapped it with graphite lube and thought that fixed it. But it may have broken when I turned, and the whole thing with running out of gas was just a coincidence.
It would make sense. It sounds like it's starting but dies when I release the key and it pops back to Pos 3.
Tomorrow I'm going to the wrecker and see if I can get another one.
"What do you use to clean it? I used a long zip tie to go in to the top and bottom, but I think it's plugged or constricted somewhere deep inside.
I'm just curious -- if these get plugged, why would that cause a no-start?"
James
The plugging of the drain hole allows water to get into fuel tank as car sets out in the rain or goes thru a car wash... then rust contamination or water into fuel rail.
To clean hole, I use old single use wire clothing hanger, straightened out with the business end bent over 1/4" and crimped in a vise. Push and turn slowly from top to clear debris.
Rgds
David
Last edited by David84XJ6; 07-19-2021 at 04:09 PM.
yachtmanbuttson yachtmanbuttson is offline
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As it turns out, my switch went back together rather well and did indeed spring back from the start position. So... there is no trick to putting the switch back together, except for the little ball and spring lining up. Mark positions of all items before taking them apart will ensure going back together the same. Take pics. Lubricate with dielectric grease lightly. Sliding contacts like that. Point to point contacts, not so much (like relays).
Don't be afraid to take switches/relays/plugs and jacks, etc apart using great care obviously. LOTS of electrical gremlins can be alleviated by clean electrical contact. I used to be a Field Engineer for a big computer company back in the day. And I earned a reputation of a real sharp shooter in New England. And mostly what I did was travel to troubled computers (generation 2 with plug in circuit boards - 2 flip flops to a board - oh the old days) and pulled each and every card, cleaned the contacts and reseated them. Problem went away. I'm a Hero! Pretty basic. Same situation with our 40-50 year old cars.
__________________
Bill Watson - Palm City, Florida (formally CT)
Rgds
David
Last edited by David84XJ6; 07-19-2021 at 04:55 PM.
Thank you, I appreciate it (both the quote and the coat hangar idea).
Went to the junk yard today and got the ignition switch. Someone had beat me to it but left it in pieces on the floor. I'm not sure if/what I'm missing. It gives me a good idea of what's going on, though.
I'm going to try to another one--I have two more possible junk cars to try. I'm hoping to get one that's intact that I can pull apart--that way I can verify whether I'm missing springs, ball bearings, etc. Also a good source for spare parts. Then I'll take my own out and give it a shot. I'm not averse to doing it (I had the power resistor pack open the other day to see what it looked like), but I like having another one on-hand as a parts donor and a practice cadaver, just in case things go bad.
I got the electrical portion of the switch (the one in my car) off, cleaned the contacts, and managed, eventually, to get it re-seated.
In POS 3, I now get dash lights (I hadn't noticed before) and I get 12V on the injectors, where before I was getting nothing.
Unfortunately, now when I twist to start--no crank. Nothing. As if the battery were disconnected (it's not).
I notice I have a wire disconnected--I have no idea if it's part of the problem, because I have no idea what it is. Would someone please tell me what it is and where it goes?
Two photos at different angles so it's hopefully easier to identify.
I think that's part of the dash light system. It has glass fibre that takes the light from the main light source under the console to the ignition switch. Not exactly sure where it goes but look for a hole in the switch surround. It should just push in.
Con
Last night said I was Jacob Marley from A Christmas Carol. Got the ignition back together but no crank. Had voltage where I needed it with key in Pos 3. The all-time 12 worked. Other electrics worked.
I visually checked to make sure I hadn't yanked a wire by accident (that's been known to happen), but everything was intact. I found a thread on how to check the starter relay, which involved pulling the white/red wire and shorting it to the battery positive to hotwire the car. The car cranked but would not catch.
Checked spark at #1 plug. Nothing.
Went back to check on the coil and realized that I had unhooked a wire on the coil to check continuity between it and pin 1 on the ECU--never put the wire back on. Connected it. Hotwired the car. It started.
Now it's in my garage and out of the broiling sun, so I can put the panels and such back on at my leisure. Will also drain and flush the tanks, add a pre-filter in front of the pump.
Thank you again, everyone who helped me. You saved me having to tow it to a shop and god knows what the bill would be. Plus I learned a lot of new stuff. I appreciate it greatly.
1. did I miss that one. Crank, fires and dies!!!!!! Huge clue. Including as you say. the ignition switch. I had an issue with mine. solved. NOS from David Boger at everydayxj. goood guy, good prices, good service...
2. Jump from battery + to coil + and iI strongly suspect the thing will not only crank and fire, but continue to run.
3.. Probe coil + with key in run. I suspect no volts!!!!!
4. Why? Switch bad or whte wire loose or busted...