[Ghostsoldier]

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

Guys,
Just a quick, armchair diagnosis from you, before I go out and jack/lift the front of the 2000 Eldo off the earth and try to squeeze my fat body under there:

About a week a go, I started to smell a slight odor, similar to burning rubber or plastic, coming from the middle to rear of my Eldo; I thought perhaps it might have been a plastic Walmart bag I somehow picked up on the undercarriage while driving, and maybe it was this that I smelled burning...I figured it would soon go away on it's own.

Not so...now a week later, the smell is still there (although slight), but now I've developed a rattling...no, more like a thumping...noise in rapid succession, somewhere on the underside of the car; you can feel it through the floorboards, like it's in direct contact with the body.

Also, the "Check Engine" light starts to flash when I'm pulling up hill, or if I gun the accelerator...if I take it easy and baby the gas pedal, it's not as bad, but it's still there, and it will eventually go off (until the next hill).

And, call it weird, but I can definitely 'feel' a difference it how the car runs...it's not up to it's usual N* par, if that makes any sense.

Any ideas, before I go out Christmas Eve to bust a gut (and my knuckles) under my car? :hmm:

Thanks (as always)!

Rob

 

[MoistCabbage]

Sounds maybe like a melted catalytic converter. Have you pulled the codes?

 

[Ghostsoldier]

Not yet; I cleared the PCM codes Friday before I left work, so I would have a clean slate; I drove home the 30 miles, and then shut it off.

I haven't cranked it back up yet, but I will go out tomorrow and get them, and post back here.

Rob

 

[basscatt]

a flashing check engine light is a SEVERE MISFIRE -

you will probably have a P0300 code - among others -
P0300 is a generic misfire code - our on-board code readers will not display
the specific cylinder/cylinders misfiring -
but a hand-held scanner will -

take your car to a big auto parts chain store - they will check for codes for free -

pay attention to the P030X codes -
P0301 is cylinder #1 misfiring - P0302 is cylinder #2 - P0303 is #3 - etc -

when you list your fault codes - include whether they are Current or History -
and remember to include the DEFINITIONS of any/all codes you might have -

 

[MoistCabbage]

I missed the part about the FLASHING SES light.

 

[Submariner409]

^^^ Yeah, that. He toasted the cat - that was the smell - floor pan insulation burning: Those things glow red hot when you're dumping in raw fuel due to a severe misfire (SES flashing - the catalytic converter damage warning is in the owner's manual).

 

[Ranger]

Next thing to figure out is WHY it's dumping raw fuel. Might start with a check of the FPR.

 

[Ghostsoldier]

OK, Ranger...what's the "FPR"?

And, will my car erupt into a ball of flame if I try to drive it very far? :shocked:

Rob

 

[Ranger]

FPR = Fuel Pressure Regulator.

No it won't catch fire. If it is leaking, the leak is being ingested into the intake manifold via the vacuum hose, thus the (unmetered) raw fuel. Just pull the vacuum line (red arrow) at idle and look for any sign of fuel at the nipple. Your will look slightly different in as much as you will have a steel fuel rail as opposed to the nylon one pictured (yellow arrow).

 

[Ghostsoldier]

OK, fellas....here's what I found:

Checked the FPR like ranger suggested....no fuel leakage, just suction at the tube at idle.

Crawled under the car after jacking it up, and manhandled the whole system...nothing is loose, nothing looks toasted. HOWEVER, I did find the source of the smell: Just as suspected, a plastic bag was wrapped around and melted to the exhaust pipe, right at the curve (in front of the rear pass wheel) where it cuts back into the mufflers under the trunk...it's black, melted carcass is still coated around 3/4 of the pipe, and still reeks of fiery death.

This doesn't 'splain the flashing SES light, the thumping, or the crappy performance, though....here's the codes and definitions I pulled this afternoon (current are bold):

P0300 C - Engine Misfire Detected
P1381 C - Misfire Detected - No Communication with Brake Control Module

B1552 H - Keep Alive Memory (KAM) Error

B2710 H - PASSKey Open/Shorted Pellet
B2711 C - PASSKey Open/Shorted Pellet After Good Key
B2750 H - PASSKey Data Communication Failure
B2780 H - Wrong Resistor Before Good
B2781 H - Wrong Resistor After Good

B1341 C - Air Mix Door Two Movement Fault

B1350 H - Engine Coolant Over-Temperature

C1223 H - Left Rear Wheel Speed Sensor Input Signal is 0

Some of these are familiar to me: I'm also getting the "Theft System Problem, Car May Not Restart Yada Yada yada" message (another thing to figure out), and I know, too, that the passenger air mix motor is toasted (gotta replace it)--the overheated coolant code is because I have a bad head gasket, as I had to drive it in camel mode a week or so ago, to get it off the interstate and home...the wheel speed sensor code and the KAM errors baffle me, but I'm thinking they won't cause the car to run crappy and thump as I drive...

Any ideas of what it could be? As Sub hinted, is there any way to check the converter by taking it to O'Reilly's or AutoZone for a code check, as basscat suggested?

Rob

 

[Ranger]

A bad CAT "SHOULD" set a DTC.

but now I've developed a rattling...no, more like a thumping...noise in rapid succession

Failed front motor mount. Pretty common.

 

[Ghostsoldier]

Thanks, Ranger...I was hoping it would be a cheaper fix! I'll check it out later this week....right now, I'm going to eat some pie and eggnog! :bouncy:

Have a Happy Holiday, everyone! :thumbsup:

Rob

 

[Ranger]

You might consider a set of torque struts to prevent future failures.
http://www.cadillacforums.com/forum...3-fabricated-torque-strut-2000-northstar.html

 

[Ghostsoldier]

I've got a couple of aluminum dog bones up top, Ranger... are those torque struts?

Also, can anyone point me in the direction of a tutorial for changing that front motor mount?

Rob

 

[Ranger]

Yeah, those would be torques struts. Didn't realize that the Eldo retained them.

 

[Ghostsoldier]

OK, fellas....I swapped out the front right mount, using this tutorial:

http://www.cadillacforums.com/forum...forum/4381-how-replace-front-motor-mount.html

It worked like a charm, in about an hour...if you have an Eldorado, this is definitely the one to use. :thumbsup:


Here's what the old mount looked like:

As you can see, it was pretty much toast...rubber falling out, soaked with oil, and you can flex it with hand pressure.

I thought I had it fixed, but now I think the left one needs to be replaced, too, because it seems to be broken...the exhaust pipe thumping is just as bad (if not worse) when you accelerate, and when you power brake it in gear, the N* is still 'climbing' up under torque, although not as much as it did before.

I'm assuming there should be no noticeable raising-up of the engine under torque; I'll try to take a video of it tomorrow to post here, so you can see.

Dummy that I am, I only ordered one mount, so now I've got to get another one for next weekend....the fun never ends. :banghead:

Rob

 

[basscatt]

have you addressed the misfire yet?

have you discovered which cylinder/cylinders is/are the problem?

 

[Ghostsoldier]

No, not yet, BC...I was going to try to get this fixed first, then turn my attention to the misfire issue.
Rob

 

[Ghostsoldier]

UPDATE:

Okay, fellas....here's the skinny: I crawled under the Eldo today, and discovered the source of my rattling....seems that the front cross-brace bar (the one immediately) behind the cat) had been bent and pushed upwards, to the point where the exhaust pipe was rattling and bumping to beat the band; it looks as if it had been done several years ago, and just now has begun to manifest itself. I pulled it off, hammered it back (maybe a little over-arched in the opposite direction, just to be safe), replaced it and solved that issue.

Now, the reason it began to do this, now of all times, became apparent whenever I studied the left front trans mount....like the right front motor mount, it too has developed a leak and has collapsed, with oil cascading everywhere; no doubt the shifting of the engine alignment caused the exhaust pipe to begin rubbing, where it has not for so many years. I promptly ordered a new mount, and should be able to install it sometime next week (it doesn't appear that it's going to be as challenging as the motor mount). Also, while I was under the car, i checked the rear trans mount, and it looks fine (it appears to be solid, not hydraulic, but I may be wrong).

Now, on to one more issue I discovered: Apparently, 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. My question is this: Is there an o-ring seal that I might have damaged, or is the FPR something that can't be removed and replaced (as in, once out, it needs to be replaced with a new one)?

I haven't done anything to it yet, as I wanted some opinions first...depending on what you guys tell me, I'll try to fix it tomorrow.

Rob

 

[98Geldog]

If u remove it gas will come out that's ok . There is a ring around it.just remove it and make sure it's seated correctly .