Another 89XJS failing to start
#1
10-30-2007, 05:22 AM
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Another 89XJS failing to start
5.3L V12 ran just fine last week. Now will turn over but not start. Suggestions for checking most likely culprits? Somewhere, and this could be all wrong, I read tolisten for the fuel pump (turning off after a few seconds when key turned halfway) and to also try starting while feeling and injector or two to see if they are clicking. I think I hear the pump turn off but I feel nothing on the injectors. Thanks in advance,
#2
10-30-2007, 12:01 PM
RE: Another 89XJS failing to start
Well, if it's turning over, then the basics are down pact. Now it's one of two things, either fuel, or spark. I would check spark first, since it's easier than fuel. If neither of those is the culprit, I would check compression, although it if it was running perfectly fine last week it's not likely that it's blown. Engines tend to give signs of death. Not too familiar with these beasts, but a car is a car, just my 2 cents.
#4
10-31-2007, 01:03 PM
RE: Another 89XJS failing to start
Bigdreams05 is right on track with this... Check the spark and then the fuel.
Checking the spark... Assuming that you have plug wires... I'm not familiar because I haven't had the luxury of owning a V12
.
First, check the plugs... If they are terribly fouled, replace and try to start. If they are ok, then continue on... The correct way is to get a spark testing tool which is about $10 at the parts store. It plugs into the plug wire just like a spark plug and has an area in it that will show you the spark. If you don't want to get one though, you can go the cheap way and use a screwdriver. Pull one plug wire and put the end of the screwdriver into it, making sure that the end of the screwdriver touches the metal. Rest the screwdriver on the motor or frame, making sure that the shaft of the screwdriver is near metal... 1/2" or so is fine - if you just place it on a metal peice, that will work. DON'T HOLD THE SCREWDRIVER!!!! Have someone try to start the car and see if a spark jumps from the screwdriver to the metal. Repeat for each cylinder. If you don't have spark, then first try to replace the wires. If that doesn't work, then troubleshoot the ignition.
Checking the fuel...
Simply hearing the fuel pump pressurize when you turn the key isn't enough. Fuel pumps have a tendency to still work, but not at a high enough pressure. They kind of "half way" work. So you will still hear it activate, but it wont be pushing enough pressure to supply the fuel needed. The best way to test it is to get a fuel pressure testing guage (probably about $30 from a parts store). Usually, I am all for taking the cheap route, but this is an invaluable tool that you will use a ton of times if you work on your own cars. Buy the tool. Hook it up to the schrader valve on the fuel line and turn the key to the on position. Compare the pressure to the car's specifications. If it is low, replace the pump. The cheap test if you don't want to buy the guage is to pull the plugs and pour a tiny bit of gas into each cylinder. Replace the plugs and try to turn it over. It wont start, but it will sound like it's about to. Basically what you are doing is putting a small amount of gas in the plugs to simulate the pump supplying the fuel. The gas burns off right away, so it wont start... but if all it was doing was cranking before and now after you did this it stumbles like it is about to start, fuel pressure is your problem. I would suggest buying the guage though... This isn't the safest test. lol.
Checking the spark... Assuming that you have plug wires... I'm not familiar because I haven't had the luxury of owning a V12
.First, check the plugs... If they are terribly fouled, replace and try to start. If they are ok, then continue on... The correct way is to get a spark testing tool which is about $10 at the parts store. It plugs into the plug wire just like a spark plug and has an area in it that will show you the spark. If you don't want to get one though, you can go the cheap way and use a screwdriver. Pull one plug wire and put the end of the screwdriver into it, making sure that the end of the screwdriver touches the metal. Rest the screwdriver on the motor or frame, making sure that the shaft of the screwdriver is near metal... 1/2" or so is fine - if you just place it on a metal peice, that will work. DON'T HOLD THE SCREWDRIVER!!!! Have someone try to start the car and see if a spark jumps from the screwdriver to the metal. Repeat for each cylinder. If you don't have spark, then first try to replace the wires. If that doesn't work, then troubleshoot the ignition.
Checking the fuel...
Simply hearing the fuel pump pressurize when you turn the key isn't enough. Fuel pumps have a tendency to still work, but not at a high enough pressure. They kind of "half way" work. So you will still hear it activate, but it wont be pushing enough pressure to supply the fuel needed. The best way to test it is to get a fuel pressure testing guage (probably about $30 from a parts store). Usually, I am all for taking the cheap route, but this is an invaluable tool that you will use a ton of times if you work on your own cars. Buy the tool. Hook it up to the schrader valve on the fuel line and turn the key to the on position. Compare the pressure to the car's specifications. If it is low, replace the pump. The cheap test if you don't want to buy the guage is to pull the plugs and pour a tiny bit of gas into each cylinder. Replace the plugs and try to turn it over. It wont start, but it will sound like it's about to. Basically what you are doing is putting a small amount of gas in the plugs to simulate the pump supplying the fuel. The gas burns off right away, so it wont start... but if all it was doing was cranking before and now after you did this it stumbles like it is about to start, fuel pressure is your problem. I would suggest buying the guage though... This isn't the safest test. lol.
#5
11-10-2007, 08:37 AM
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Posts: n/a
RE: Another 89XJS failing to start
Thanks very much for the replies to my post. I have been in and out of town the last two weeks and only today can return to my baby. I tried starting her this morning, hoping that the passage of time would solve the problem, but no luck.
To answer the first reply--I believe I have the Lucas. It is blue in color, larger in diameter, and has short connecting posts. I believe that is the Lucas, at any rate. I will be going to parts store this morning to pick up a plug tester. On other advice, I did try removing the HT lead from the middle of the distributor cap and, holding it about 1/4 inch from engine, see if I could see a spark when cranking. No is the answer. I do have a voltmeter--Can I measure directly from the HT lead? If yes, what would I expect to see?
My plan is to try and rule out electrical first before looking to fuel. I should point out (it is probably obvious) that I am no mechanic and I am learning as I go. Thanks very much in advance for your help.
UPDATE: Purchased a spark tester this morning, one which is designed to measure through the spark plug wire. Nothing. Although the casing on those wires is quite thick and the only tester I could find was, well, pretty cheap. I did try my multimeter. I disconnected the lead from the middle of the distributor cap and put themeter between that wire (coming from the coil???) and ground. Read between 9.5 and 10.0 volts while cranking. Informative?
UPDATE #2: [Am I a lone voice in the wilderness here?] Tried starter fluid this morning and she coughed a couple of times but pretty much started right up. Ran fine afterwards (30 minute drive in the countryside). This is not over, I'm sure, but I was very relieved and celebrated my good fortune with a Samuel Smith's Nut Brown Ale at 10am while ignoring commentary from my wife. Oh, and today is my 48th birthday. I think I will have another beer.
To answer the first reply--I believe I have the Lucas. It is blue in color, larger in diameter, and has short connecting posts. I believe that is the Lucas, at any rate. I will be going to parts store this morning to pick up a plug tester. On other advice, I did try removing the HT lead from the middle of the distributor cap and, holding it about 1/4 inch from engine, see if I could see a spark when cranking. No is the answer. I do have a voltmeter--Can I measure directly from the HT lead? If yes, what would I expect to see?
My plan is to try and rule out electrical first before looking to fuel. I should point out (it is probably obvious) that I am no mechanic and I am learning as I go. Thanks very much in advance for your help.
UPDATE: Purchased a spark tester this morning, one which is designed to measure through the spark plug wire. Nothing. Although the casing on those wires is quite thick and the only tester I could find was, well, pretty cheap. I did try my multimeter. I disconnected the lead from the middle of the distributor cap and put themeter between that wire (coming from the coil???) and ground. Read between 9.5 and 10.0 volts while cranking. Informative?
UPDATE #2: [Am I a lone voice in the wilderness here?] Tried starter fluid this morning and she coughed a couple of times but pretty much started right up. Ran fine afterwards (30 minute drive in the countryside). This is not over, I'm sure, but I was very relieved and celebrated my good fortune with a Samuel Smith's Nut Brown Ale at 10am while ignoring commentary from my wife. Oh, and today is my 48th birthday. I think I will have another beer.
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