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DetGeno
11-05-2003, 02:12 AM
Does anyone know what is going on? The weather here in Michigan has been up and down like a roller coaster lately. Today it was sunny 74 and warm, and yesterday was down to 30. But in the last couple of weeks when the car is running or cooling down after you turn the car off. I been hearing LOUD knockings from the gas tank, anyone has any ideas what that means? Only 6,500 miles on the beast! Thx in advance! :help: :help: :help:

RCSignals
11-05-2003, 03:42 AM
You sure it's the gas tank? Maybe mufflers?

RF Overlord
11-05-2003, 05:35 AM
Is your mother-in-law still in the trunk?

gilby04
11-05-2003, 05:47 AM
DetGeno,

I received my DTR MM on Oct 20th.
At times, I've noticed a dull, low pitched noise coming from the rear of the MM...sounds like a "bubble-gum" bubble bursting.
In no way is the sound LOUD like you're experiencing.
Perhaps a pressure differential issue in the fuel tank, or exhaust system ?
My noise issue typically occurs at cold start-up, but not every time.
Nothing seems amiss...just an odd quirk !
Hmmm...It never occurred to me that the sound may be a function of changing (ambient) weather conditions ???
gilby04

TripleTransAm
11-05-2003, 07:38 AM
I think I heard this loud pop once or twice at Hershey after a long haul. From what I hear on other car boards, it's the tank retracting when cooling. I have never heard it at home, but then again I don't usually hang around the car too long once I get home.

DetGeno
11-05-2003, 10:28 AM
I guess it could be the muffler? Just don't know? It does how ever sound like a "bubble bursting or a loud pinging noise". It's coming from the rear-end and that is for sure. Anyone has any clues, please give me your input!!!! NO IN-LAWS YET!!!

RF Overlord
11-05-2003, 10:35 AM
Geno:

I've heard similar sounds from my MM (kinda like a metallic "pong" sound), and I think it's the heat shields on the catalytic converters...my '94 T-bird used to make the same sounds when cooling off, so I haven't paid much attention to it, although it seems to be coming more from under the front of the passenger cabin than from the rear...

DetGeno
11-05-2003, 12:34 PM
Does it do any harm to the MM? Or, is there anything that we can do to prevent further noises?

Petrograde
11-05-2003, 01:02 PM
Hey Geno,..
I've heard this too,.. but here in Texas, it hasn't been cold at all. I've got about the same miles as you do,.. I first noticed a pop, or a thud? upon shut down about a month ago...

My first thought was the exhaust, hmmm,.. now that I think about it the only times I've heard it, the fan also kicks on for a few seconds.

Tom

GarageMahal
11-05-2003, 01:29 PM
Originally posted by RF Overlord
I've heard similar sounds from my MM (kinda like a metallic "pong" sound)

This summer after running hard (80+ MPH) for a couple hours I would hear a 'Ding!' a few minutes after I stopped and shut down the engine. I was able to reproduce this at each stop on a road trip and it would occasionally happen twice per stop.

I determined it was coming from the exhaust tips. I find it quite entertaining actually. It is a good clear note almost like a bell being struck once.

jta

DetGeno
11-05-2003, 01:31 PM
Very interesting! Maybe a dealer rep on this site can help us with this issue?

RCSignals
11-06-2003, 01:47 AM
Sounds like, as RF said, the shields on the cats suddenly cooling after shut down or at heating at start up maybe if it's very cold outside

DetGeno
11-06-2003, 02:15 AM
Thx everyone! I thought I left my Ex in the tank some how, now I know is not just me!

gonzo50
11-08-2003, 05:04 PM
Originally posted by GarageMahal
This summer after running hard (80+ MPH) for a couple hours I would hear a 'Ding!' a few minutes after I stopped and shut down the engine. I was able to reproduce this at each stop on a road trip and it would occasionally happen twice per stop.

I determined it was coming from the exhaust tips. I find it quite entertaining actually. It is a good clear note almost like a bell being struck once.

jta
I've heard mine do the same "bell being struck once" sound on days that was very cool in the mornings and I've only driven for a short distance, about 10 miles. Interesting ! :confused:

MMdriver03
11-08-2003, 05:26 PM
I get the same noises from day one... I always thought its just my exhaust rapidly cooling down.

SergntMac
11-08-2003, 09:28 PM
I hear all sorts of cute noise from my MM. Some after a long run on a cool day, and others from cold starts on very hot days. Actually...Now that I think about it, my MM makes a lot of noise in between too.

I think the soprano range "tink" I hear after a hot run on a cool day is my exhaust system dealing with the change in temps.

The "knock" I hear inside my MM on startup, and during hot idle (bumper to bumper with less than a half tank of gas) is probably my fuel pump. Before you jump on this, my fuel pump isn't OEM.

I have a WalBro 255, which can get noisey almost anytime it wants to. It can "bang" against the side of the tank when it wants juice and this noise really starts to shout at me just about the time my low fuel light comes on.

I'm okay with this. If I'm on the highway, I may lose track of fuel consumption, and this "knock" kinda says to me "hey, stupid, I'm hungry." Cool...

I hear a "creak" from my right rear suspension during slow and tight right turns to elevated grades. This is probably my "body on frame" construction expressing discontent with my turn. Sounds a whole lot me getting out of bed on a chilly AM, so, I have some sympathy here. Go figure...

I hear a "metal on concrete" scraping noise if I pull out of my garage too fast. This is due to my lowered ground clearence, and my elevated garage apron. Both me and my MM, K? We're both heavy and low...

When the City of Chicago re-paved my alley, they dug up the old stuff to install sewers, then started fresh. It's about 2" lower in the center now, for water drainage I suppose. So, if I "launch" out of my garage too hard, my tailpipes will contact the pavement.

Okay, it's a "known cause and effect" noise, but it's a sound I hear every "now and then" and I'm listing them all now.

I hear a loud "hiss" at start up. Power on, before ignition, and again at idle.

Actually, I hear almost it always. This must be the 7" 400 CFM Derale fans I've added to the heat exchanger behind my grill, and the trans cooler in the left front. They sing a duet ya know, and I like this "hiss" at the stoplight.

My MM also "farts," or, "sneezes" depending on how you feel about this noise.

Its more like a nasal "fhittttsss," (a soprano fart?). This is my "blow off valve" on my Vortech/Kenny Brown supercharger, a waste gate for unused boost.

When I get into the throttle hard, and suddenly back off, (like in burnouts), the "charged" air has to go somewhere. This is one of two basic differences between the KB design and the Reinhart design. KB installed a waste gate while DR recirculates the charged air. I do not believe either design has any impact on performance, both are reactions to a closed throttle. But, it's a cute noise, Haggis calls it a "whistle."

My in-dash DVD "whirls" while the screen opens.

I don't "whirl" anymore.

My cigarette lighter "pops" when ready.

I can "pop," only "when ready."

My I-PASS "beeps" when I pass through a toll booth.

I never "beep."

My Stallion triple plate torque converter "chatters" at idle, in park or neutral.

"Idle Chatter?" Ummm...Here at MM.net?

Oh, come on now...

My Passport 8500 plays several tunes. Some are diagnostic at power up, others are warnings when a radar signal is detected, dependent on strength and distance. My CB radio has likewise power-up diagnostic tunes and close range signals.

Shame my ex-wife never had these features...

My on-board air suspension will "burp" a monotone "barrrruuummmpppp" every now and then.

I do this too, and on a regular basis. In fact, I'm "regular" because of this.

My remote mirrors "whine" while I adjust them. But, I hear this from most of my office staff. Lazy louts!

My window washers "squirt."

I haven't "squirted" anything since my 30's!

My window wipers call me names once it's stopped raining..."Dumbguy,dumbguy, dumbguy..." Ditto my ex-wife, I should learn a lesson here, eh?

My tires "squeal" in pain when I trounce on others at the get-go, and I don't get this. It's the other guy I'm putting a hurtin on, why are my tires crying "stop it!"? But, they also "screech" when there is another "dumbguy" in front of me on the highway.

My glove boxes "snap" and "click," and all of them too!

The only "snap" and "click I have left today, thank you...

Light switches, seat belts, door locks, all "clickers" in several tones and tenors. A real symphony, she is! And, the only symphony in my life today. She's a real "keeper" eh?

Now...If only I could all these noises to play together, and hold a 9/8 time signature... I could have a new bagpipe tune to play, maybe even a top 40 hit!? Surely, the "techno/warhouse" lovers could have some fun with all this industrial noise...I do!

Anyone here interested in recording my MM?




Oh...

Never hurts to ask, eh?

TripleTransAm
11-08-2003, 09:44 PM
:lol:

Abso-freaking-lutely hilarious...

rumble
11-09-2003, 08:24 AM
Cool! Once again the Sarge exceeds expectations. Although,
Sarge, I truly think you have to be our age to appreciate all
those experiences.

TooManyFords
11-09-2003, 08:46 AM
Ywah. we'll record your MM as long as we don't have to record you too! :D:D:D

john

jgc61sr2002
11-09-2003, 04:56 PM
Sarge - Very cool. I can relate to some of your statements.:cool: :D

DetGeno
11-10-2003, 09:47 PM
Thx Sarge!!! :up: Glad to know it's not just me!!!!

gilby04
11-10-2003, 11:05 PM
Mr. Sarge,

Very impressive list, indeed.
Your itemized list of noises is most comprehensive, without equal, I'm sure.
I certainly sympathize with you about your cigarette lighter popping only when ready...I have one of those lighters myself.
Most annoying, eh ?
It's been said by many old-timers that either Vaseline and/or Windex, in the proper proportions of course, can help with many lighter issues.
I'm not positive, but perhaps the solution to all the other noises can be resolved with tweaking the radio volume control knob.
You're a good sport, Sarge,
Take care,
Jim

ik04
11-10-2003, 11:20 PM
I had a former spouse who fixed the grinding/howling noise from the self-destructing oilless differential/final drive in her car by turning up the volume on the radio. Really.

Kevin