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There are two O rings (1 large and 1 small) in the FPR. Relieve the fuel pressure, pull the regulator and reseat both O rings. Put a drop of motor oil on them before you reinstall it.

 

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2000 Eldorado ESC; 1974 Dodge Monaco 440 Police package
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Discussion Starter #22
Thanks, guys! :) How do I relieve the fuel pressure? Can I just wrap a shop rag around the FPR, pull the clip and let it boil over?

If so, will the system re-pressurize when I start the car?

Rob
 

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There's a Schrader valve. (Like on a bicycle tube) on the fuel rail. Have a rag ready, and push the valve core pin in with a small, pointed tool.

You may have to "prime" the system, by turning the key to on, until the fuel pump stops, then off, and in again..... Repeat ~3-5 times or so.
 

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Discussion Starter #24
Roger that, MC...I'll try it tomorrow, and let you know what happens....now I'm wondering if this is what's throwing the code and triggering the SES light, since the injectors aren't getting their just deserts, as far a fuel feed.

Rob
 

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Master of the Dark Art of Diagnostics
2003 DHS - two-2002 DHS, 2003 SLS, 1995 Sedan DeVille, 1989 Coupe DeVille
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Roger that, MC...I'll try it tomorrow, and let you know what happens....now I'm wondering if this is what's throwing the code and triggering the SES light, since the injectors aren't getting their just deserts, as far a fuel feed.

Rob
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now I'm wondering if this is what's throwing the code
and triggering the SES light

I still think you have an ignition coil problem -

the FPR problem you have now was "self-inflicted" -
and started AFTER the original P0300 misfire code - correct?


when I was checking the fuel pressure regulator hose for vacuum leak last week,
I forgot to mention that I actually removed the spring clip
and pulled the regulator out a little (not knowing what I was doing);
when fuel began to spew out under pressure, I panicked and pushed it back down,
re-installing the clip as fast as I could.

That appears to be the source of my gas smell...
now when I crank the car, I can smell and see fuel leaking from the bottom of the FPR
 

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Discussion Starter #26
You're exactly right, BC...I'm getting dumber in my old age, or forgetting the order in which all these myriad things are happening with this car...the P0300 and flashing light was before the FPR fiasco, so I'm back to square one on the misfire issue...*sigh*....well, I'll fix the fuel issue, and then move on to the P0300 problem, like I originally intended.

Thanks for indulging me, and for all the patience!

Rob
 

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Master of the Dark Art of Diagnostics
2003 DHS - two-2002 DHS, 2003 SLS, 1995 Sedan DeVille, 1989 Coupe DeVille
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You're exactly right, BC...I'm getting dumber in my old age, or forgetting the order in which all these myriad things are happening with this car...the P0300 and flashing light was before the FPR fiasco, so I'm back to square one on the misfire issue...*sigh*....well, I'll fix the fuel issue, and then move on to the P0300 problem, like I originally intended.

Thanks for indulging me, and for all the patience!

Rob
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as I said earlier - I believe the problem to be a bad coil -

go back and re-read post #4 -
once you discover WHICH cylinder is misfiring - report back -

my plan is to swap coils - to verify the bad coil - or not -
and of course - inspecting the boot and spark plug of the misfiring cylinder

the coils are identical - except for the color-
and are completely interchangeable -

example - if the original misfire is from #2 -
after swapping the coils - the misfire should switch to #7 -

if it does - the front coil cassette is bad -
 

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Discussion Starter #28
Wow, I didn't know that about the coil packs; I thought they were independent of each other, as far as the application. I'll try to isolate the cylinder via a handheld tester at a parts house, and then try the cartridge swap method, and let you know what happens.

BTW, all the plugs are brand new, as well as all of the coil boots...I replaced them all about a month ago, with GM parts. ;)

Rob
 

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Wow, I didn't know that about the coil packs; I thought they were independent of each other, as far as the application.
I think the '04+'s are, but the '00 - '03's all one piece and encapsulated in the ignition cassette.

Courtesy of Submariner409
 

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Discussion Starter #30
Yep...that right there is what I have two of, on my Eldo. :)
Rob
 

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Discussion Starter #31 (Edited)
Okay fellas, it's time for an update..... I changed the other mount, only to find out that the bracket itself was loose, apparently from all the vibration of the first bad mount; since I was already in there, I went ahead and installed the new mount, anyway....vibration/shuddering problem solved.

Now, on to the misfire...I haven't had a chance to have it checked with a diagnostic machine yet, but I wanted a little clarification in exactly what a "misfire" is: Does it imply that the spark plug isn't firing (denoting an issue further upstream), or does it mean the plug is in fact firing, but perhaps it's a fuel issue, leaking head gasket, etc, that's throwing the P0300 code?

Does my question even make sense?

Rob
 

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Re: Rattling/thumping on floorpan, Check Engine (SES) light

Yes - all the above: For some reason one or more cylinders is/are not doing its fair share of power production. You need to find out which cylinder(s).
 

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Discussion Starter #33
Re: Rattling/thumping on floorpan, Check Engine (SES) light

Ok, Sub....I gotchya. ;) I took it down to O'Reilly's, they hooked up the diagnostic machine, and it said cylinder No. 5 is the culprit....consistently, it seems.

So, now that I know this, I'm going to do the following:

1) Rent the pressure tester for the cylinder...see if it leaks down, and then I'll know it's the head gasket. I say this, because I'm not convinced (yet) that I've got that problem; I used the block tester, but never really got the liquid in the tube to turn yellow...it faded out to a clear, but it never turned piss yellow, or otherwise, then

2) Rent a pressure tester for the cooling system; if it's not a HG problem, then I need to find where the antifreeze is going....I can't find a visual leak, but it may only be leaking under pressure, then

3) Rent the noid set, to test the injectors, then

4) Swap the coil packs, to see if the No. 4 cylinder is the new culprit....then I'll know it's the cassette.

Any more ideas or suggestions?

Rob
 

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That outta do it, but you should be able to listen to the injectors with a stethoscope or screwdriver. If the injector is working you'll hear the same rhythmic ticking as all the other injectors.
 

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Discussion Starter #35
Roger that. I'm going to give it a go this weekend, and I'll come back here and let you guys know what happens. :)

Rob
 

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Master of the Dark Art of Diagnostics
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Re: Rattling/thumping on floorpan, Check Engine (SES) light

Ok, Sub....I gotchya. ;) I took it down to O'Reilly's, they hooked up the diagnostic machine, and it said cylinder No. 5 is the culprit....consistently, it seems.

So, now that I know this, I'm going to do the following:

1) Rent the pressure tester for the cylinder...see if it leaks down, and then I'll know it's the head gasket. I say this, because I'm not convinced (yet) that I've got that problem; I used the block tester, but never really got the liquid in the tube to turn yellow...it faded out to a clear, but it never turned piss yellow, or otherwise, then

2) Rent a pressure tester for the cooling system; if it's not a HG problem, then I need to find where the antifreeze is going....I can't find a visual leak, but it may only be leaking under pressure, then

3) Rent the noid set, to test the injectors, then

4) Swap the coil packs, to see if the No. 4 cylinder is the new culprit....then I'll know it's the cassette.

Any more ideas or suggestions?

Rob
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1) Rent the pressure tester for the cylinder...
see if it leaks down, and
then I'll know it's the head gasket

that's a giant waste of time on a Northstar motor -

I used the block tester,
but never really got the liquid in the tube to turn yellow...
it faded out to a clear, but it never turned piss yellow,

WAIT A MINUTE - when did you do the BLOCK TEST?

STOP EVERYTHING -

YOUR HEAD GASKETS ARE BLOWN -
the blue liquid reacts to exhaust gasses -
ANY COLOR CHANGE - is a POSITIVE reaction -
even the slightest change to a lighter blue is a positive reaction -

the higher the concentration of hydrocarbons - the "yellower" the color -
light blue - you are the early stages -
almost clear - more exhaust present -
green - even more hydrocarbons -
yellow - the strongest reaction -

2) Rent a pressure tester
again - don't bother -

3) Rent the noid set, to test the injectors,
a noid will only tell you if the injector is getting the "fire" signal -

use a stethoscope - or simply a long-handle screwdriver -
and with the engine running - listen to each injector -
you will hear a very steady ticking sound it it's working -

it's worth knowing - and only takes a few minutes -

4) Swap the coil packs, to see if the No. 4 cylinder is the new culprit
also worth doing to verify whether the coil cassette needs to be replaced -

BUT - all the above information is only important IF
you are planning to do the head gasket repairs -

sorry to be the barer of bad news -
 

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Discussion Starter #37
Re: Rattling/thumping on floorpan, Check Engine (SES) light

Not ignoring basscat's post about a possible head gasket issue, as I appreciate his valued insight, but I'm incredibly hard-headed in accepting that diagnosis; until I have ruled out all the issues that I'm questioning at this time, I'm gonna keep stabbing at possible culprits. Maybe I'm dumb and blind and fooling myself, but I gotta try. :yup:

That being said, I went ahead and swapped out the coils to see if the No. 5 cylinder misfire would 'jump' to No. 4; I had also cleared the PCM codes, so now when I take it down to O'Reilly's for another test, they get the generic P0300 "random misfire" code I do. The guy tells me I have to tun it for a few cycles to 'lock' in a specific cylinder misfire...meh...I don't know enough about how that works, so I guess I'll run it a bit longer and take it back down there later this week, to see if we can pinpoint it again. SES light is still flashing. :annoyed:

I have heeded basscat's advice about forgoing the pressure tests at this time, though; I want to run some new stuff I discovered by you first.

Cooling system pressure: I notice I don't have any. I could run this car for 200 miles, take the cap off, and there's NO pressure release, no boiling over, nothing...although the reservoir is usually about 3 quarts low. I'm assuming that if I have a bad cap, the system could be venting my fluid at highway speeds, and I would never know...is this correct?

Either way and to be safe, today I bought a new cap, put it on and drove the 1 mile to home, and when I checked it, I got a "pop" of air pressure release when I turned it. Hopefully the problem of fluid loss is solved; time will tell.

Fuel injection system
: Today I ran the car, and got this horrific new smell of emissions/fuel smell, plus the really worse-than-usual, sputtering pulpwood truck, misfire condition. Last week while driving it to work, I could feel the car "surge" under power at highway speed, on-and-off, like it was trying to smooth out, but couldn't. I checked the FPR again for leakage, but found none. SES light is still flashing.

Although I haven't rented the noid set yet (this weekend was my wife's birthday, so Saturday mechanic'n was OUT, lol :tisk:), I did decide this afternoon to try a shade-tree test on the injectors by trying the screwdriver-stethoscope sound test. Although I did get the rhythmic fast 'ticking' at each one, I decided to pull off each wire connector while the car was running to see if I could hear or feel a noticeable change...and lo-and-behold, I could, on cylinder No. 1 and No. 4.

northstar_firing_order.gif

When I pulled the other leads off and back on, I could hear and feel the engine change; when I pulled these two off, and left them off, there was no change. I plugged them in, no change.

I guess my next move will be to rent the noid set, to see if the PCM pulse is getting to the injectors; if it is, can I assume I have two faulty fuel injectors (I understand they cannot be cleaned)? :confused:

Rob
 

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Re: Rattling/thumping on floorpan, Check Engine (SES) light

Deleted. Incorrect information for wrong year group engine.

BUT - Cylinders 1 and 4 are at the same position relative to crank rotation in the firing order: Cylinder 1 fires and exactly one revolution after that, #2 fires. I wonder if there's a hiccup in the ignition trigger signal for those two cylinders................ and this diagnosis is going to take a GM Tech-II scan/program tool to diagnose.
 

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I could run this car for 200 miles, take the cap off, and there's NO pressure release, no boiling over, nothing...although the reservoir is usually about 3 quarts low.
I don't think that tank will hold 3 qts. If you added 3 qts not only is the tank dry, but so is part of the radiator.


I agree with Sub. I'd replace the #1/#4 coil.
 

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Discussion Starter #40
When you guys say "replace the #1/#4 coil", how can I do that? Isn't the #1 in one cassette, and the #4 in the other?
Aren't they impossible to service, the coil pack being an all 1-piece construction?
Rob
 
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