Cannot locate fuel pressure test location. No Schrader valve on My LS V8

joegr said:
This is not making any sense to me at all.
The valves are solid metal, so there can't be oil in them.
The valve stems are soaked in flowing oil, as are the camshaft lobes. The valves themselves should be mostly dry of oil. Of course, valve stem seals can leak, but the only fix for that is replacing the valve stem seal.
There's no way for you to even see the valves without taking the intake manifold off.
Could you post a picture of what you are calling the valves?
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Those are valves, correct? Lincoln LS V8
 
John_Carr said:
Here's a clue to check.
(Added a 5v power supply to the ref side of the fuel rail pressure sensor and have it running perfectly. But I don't know why I have only 1volt on my 5v reference from the ECM? Would it be a bad ECM or Could it be it needs reflashed to adjust the voltage to proper limits? Best Wishes!
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I think you may be on to something with this. Same symptoms that my car experienced. I've checked every wire, but my vac line (like the one pictured in your message) is wrapped in the same plastic and has become brittle in many places and to top it off, I can't see the entire line because it goes back behind engine. As you probably know, these cars have extremely limited "elbow" room to be able to get your hands and eyes where they can actually find an issue (without dismantling a lot of parts). I don't understand what was meant by hooking up 5v to the ref side of the fuel rail but, hopefully, my issue can be solved by repairing (or replacing) this line. I admit that by the end of replacing my gaskets I was extremely tired, back was killing me, and I wanted to be done with it. I may have pinched that line.
 
jimmy McGill said:
The valves I'm referring to are what these coil on plugs are sitting in.View attachment 828573471...
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The COPs (Coil-On-Plug) are sitting on top of the spark plugs, which are inside the spark plug wells. The four valves that each cylinder has are situated around the spark plug well, not in or under.

jimmy McGill said:
Here is an example of the valves without the valve cover. The 4 Holes are what I am talking about. You can see inside them even with the valve cover over it and the spark plugs installed (Just need to remove the coil packs)...
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Those are not the valves. You can't see the valves, even with the valve cover off. You can only see the cams and the tappets. The 4 holes, are the spark plug wells.
 
Below is a picture of the bottom side of the LS V8 heads (removed from the engine).
On one of the cylinder positions, I have circled the four valves in red, and the spark plug hole in blue.

upload_2020-1-25_11-53-0.png
 
joegr said:
Below is a picture of the bottom side of the LS V8 heads (removed from the engine).
On one of the cylinder positions, I have circled the four valves in red, and the spark plug hole in blue.

View attachment 828573478
Click to expand...
Good to know. Ok, the spark plug wells is what I was talking about. Valve covers should be called Spark plug well covers, since the valves are already layers below the valve cover. But, tomato, potato, I just need advice on possible diagnosis of car issue.
 
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jimmy McGill said:
Any useful info would be much appreciated
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If you are concerned with faulty O2 Sensors unplug them all ....unconnect all 4 sensors ...you can unhook the MAF sensor while your at it ...see if the car fires up and runs...Dud the car fire up with starter fluid? Did you replace the starter relay?
 
AmsterDutch said:
If you are concerned with faulty O2 Sensors unplug them all ....unconnect all 4 sensors ...you can unhook the MAF sensor while your at it ...see if the car fires up and runs...Dud the car fire up with starter fluid? Did you replace the starter relay?
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it did not fire up with starter fluid. I replaced fuel pump relay, all fuses and diodes are new as well.
Ill disconnect the 02 sensors and the MAF and see if that helps
 
jimmy McGill said:
it did not fire up with starter fluid. I replaced fuel pump relay, all fuses and diodes are new as well.
Ill disconnect the 02 sensors and the MAF and see if that helps
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It's not so much as seeing if it helps but rather seeing if the car will run on a general factory fuel injector flow rate
 
AmsterDutch said:
It's not so much as seeing if it helps but rather seeing if the car will run on a general factory fuel injector flow rate
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Oh, ok. So if it does not fire up after I disconnect MAF and 02 sensors than what does that rule out? I'm trying to do whatever I can to avoid taking off valve covers again, they are a pain to get to on this engine. The bolts are hard to reach. I tried old COP's that I just replaced with new (Cheap) COP's but it did not fix the issue. Shouldn't my fuel line (the one that plugs into the driver's side fuel rail above valve cover) have fuel leaking from it when I disconnect it? It doesn't. I don't know if this is because I unplugged the fuel pump relay and turned engine over to let it cut the fuel from flowing while disconnecting this same fuel line for the purpose of removing the valve cover to begin with, or if it is another issue altogether (I have since, plugged a new fuel pump relay into fuse box). The engine started one time after I replaced valve gaskets and shook, (at idle) while revving to bleed degas system, and then died. Now it cranks and won't start. Do you know a method of checking spark without the help of someone cranking the engine while I hold a test light close to COP with spark plug inside it? Wouldn't my OBDII pick up a code if I had no spark? Sorry for the 20 questions I'm just trying to get solid answers and you have been helpful
 
jimmy McGill said:
... Valve covers should be called Spark plug well covers, since the valves are already layers below the valve cover...
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They are called valve covers for historic reasons. Note that they don't actually cover the spark plug wells either, they surround them. Note also that there are coil covers over the valve covers. Some people more accurately call the valve covers cam covers, since they do cover the cams in our overhead cam cars. They are also sometimes (accurately) called cylinder head covers.
There is a similar problem with the coils. They are correctly called COP (Coil-Over-Plug), since that is what they are. However, many call them coil packs, which they are not. The first distributorless ignition systems used coil packs. These were packs of coils (usually two or three) together, and usually each coil in the pack fired two cylinders.
 
joegr said:
They are called valve covers for historic reasons. Note that they don't actually cover the spark plug wells either, they surround them. Note also that there are coil covers over the valve covers. Some people more accurately call the valve covers cam covers, since they do cover the cams in our overhead cam cars. They are also sometimes (accurately) called cylinder head covers.
There is a similar problem with the coils. They are correctly called COP (Coil-Over-Plug), since that is what they are. However, many call them coil packs, which they are not. The first distributorless ignition systems used coil packs. These were packs of coils (usually two or three) together, and usually each coil in the pack fired two cylinders.
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Interesting. I Checked my fuses again and my 5 amp "starter relay coil" fuse is not broken or otherwise giving any indication of being blown yet my test light did not work on it. I replaced the fuse with another new one and still no light. The other fuses in this fuse box all light up fine. This is the box in the cabin (passenger side, under glove compartment). The test light did not light up when I touched the connection on the box itself (where the 5 Amp fuse goes). What would be the next step I need to take to find out where I'm losing circuit?
This is the fuse information from the manual:
Fuse/Relay Location: 1
Fuse Amp Rating: 5A
Passenger Compartment Fuse Panel Description: Starter relay coil
 
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Why are you checking the starting circuit? Your starter engages and turns the crankshaft over when you turn the key to start, so there is no problem there. Your problem is with getting the engine to run.
That starter relay fuse is only powered when the key is held in the start position.

You need to do things to troubleshoot the problem the you do have. What have you actually done?
Have you checked for 12V at the ignition coils when the key is in the run position? You need to check at least one of each bank, but all would be best.
Have you checked for 12V at the injectors when the key is in the run position?
You need to check at least one of each bank, but all would be best.
Have you tried a noid light to see if the injectors are pulsing when you are cranking the engine over? Have you tried a noid light to see if the coils are pulsing when you are cranking the engine over?

Lets do that and get the results before randomly looking at other things. Otherwise, we are going to just keep spinning in circles here.
 
jimmy McGill said:
Interesting. I Checked my fuses again and my 5 amp "starter relay coil" fuse is not broken or otherwise giving any indication of being blown yet my test light did not work on it. I replaced the fuse with another new one and still no light. The other fuses in this fuse box all light up fine. This is the box in the cabin (passenger side, under glove compartment). The test light did not light up when I touched the connection on the box itself (where the 5 Amp fuse goes). What would be the next step I need to take to find out where I'm losing circuit?
This is the fuse information from the manual:
Fuse/Relay Location: 1
Fuse Amp Rating: 5A
Passenger Compartment Fuse Panel Description: Starter relay coil
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I agree with Joe stay focused on the four basics
  • "Ingredient one: Compression. An engine needs compression to run. A compression test is a straightforward (and usually simple) test to perform. ...
  • Ingredient two: Air. Air is required to run an engine. ...
  • Ingredient three: Fuel. Fuel and air sort of work hand in hand, as we just discussed.
  • Spark is the match that lights off the burn. Spark, like the other ingredients, must occur in the correct amount."
 
jimmy McGill said:
Interesting. I Checked my fuses again and my 5 amp "starter relay coil" fuse is not broken or otherwise giving any indication of being blown yet my test light did not work on it. I replaced the fuse with another new one and still no light. The other fuses in this fuse box all light up fine. This is the box in the cabin (passenger side, under glove compartment). The test light did not light up when I touched the connection on the box itself (where the 5 Amp fuse goes). What would be the next step I need to take to find out where I'm losing circuit?
This is the fuse information from the manual:
Fuse/Relay Location: 1
Fuse Amp Rating: 5A
Passenger Compartment Fuse Panel Description: Starter relay coil
Click to expand...
Did you check your COP's Fuse in the Engine compartment? I believe there is a coil over plug relay also in the engine compartment....When you changed out the Fuel Pump Relay did you also replace the Fuel Pump fuse in the trunk? I believe it's a 15amp fuse? I'm just retracing your steps and ruling out these for sure...also did you lift your back seat cushion up and even take it out if need be to make sure the pump is turning on? you have two pumps under the back seat...but if you are getting fuel and no air leakage then I would think the SPARK is more problematic or should I say lack of spark?????
 
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joegr said:
Why are you checking the starting circuit? Your starter engages and turns the crankshaft over when you turn the key to start, so there is no problem there. Your problem is with getting the engine to run.
That starter relay fuse is only powered when the key is held in the start position.

You need to do things to troubleshoot the problem the you do have. What have you actually done?
Have you checked for 12V at the ignition coils when the key is in the run position? You need to check at least one of each bank, but all would be best.
Have you checked for 12V at the injectors when the key is in the run position?
You need to check at least one of each bank, but all would be best.
Have you tried a noid light to see if the injectors are pulsing when you are cranking the engine over? Have you tried a noid light to see if the coils are pulsing when you are cranking the engine over?

Lets do that and get the results before randomly looking at other things. Otherwise, we are going to just keep spinning in circles here.
Click to expand...

I have not checked for 12V on the coils yet. I asked if there was any other way to check for spark without someone else cranking engine while I hold a test light or screwdriver a half inch away from spark plug connected to coil on plug, but now I know there is another way. I assume a multi-meter will work fine for this test. I can do this by myself. I can't check the injectors or coils for pulse while cranking because I don't have a plug in starter or remote starter but I will be able to check the voltage by placing key in run position. Thank you, very useful.
 
AmsterDutch said:
Did you check your COP's Fuse in the Engine compartment? I believe there is a coil over plug relay also in the engine compartment....When you changed out the Fuel Pump Relay did you also replace the Fuel Pump fuse in the trunk? I believe it's a 15amp fuse? I'm just retracing your steps and ruling out these for sure...also did you lift your back seat cushion up and even take it out if need be to make sure the pump is turning on? you have two pumps under the back seat...but if you are getting fuel and no air leakage then I would think the SPARK is more problematic or should I say lack of spark?????
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Yes I did replace all fuses, and checked all relays, I replaced the fuel pump relay in trunk along with every fuse in that compartment, and you are correct, the fuel pump fuse is 15A. I'm thinking it is a spark issue. I did not know how to check that (other than having someone else crank engine while I check for spark), but with the info Joegr gave me, I now know how I can perform this test without someone else cranking engine for me. I have checked fuel pump (under backseat), it is not the issue, so I am going to garage to test COP's and injectors and make sure they are 12V. Thank you for the help.
 
Please note that a "noid" light is a bit different than a multi-meter in that it applies a slight load to the circuit under test and it is a better way to see something pulsing as most meters wouldn't be able to keep up with it. It doesn't really change the need to have two people. Surely, there are other humans reasonably near you?
 
Yes there are some people reasonably near me but they are not always home when I am able to work on car. I was hoping this was a one man job but I can coordinate a time to have someone available to help.
 
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