does anyone else have this Maraude-itty??

[RedMM]

More times than not, when starting my 04 with 500 miles on it, after sitting all night-there is a boom/skreech sound under the hood about 15 seconds or so after startup. My best quess is belt tensioner or ac compressor?? Do not happen after the first startup each day, only when completely cold after overnight sitting. I've had many retired Crown Vic PI's that have made a somewhat similar noise when compressor kicks on and also a few that had to have belt tensioners replaced because of bad bearings, but this sound is a bit different. Any thoughts would be appreciated. Car goes back to dealer tomorrow th have prnd21 glass in console replaced(cracked across 2) and alignment checked due to wandering to the right. I would like to mention this noise to dealer, but will not be able to duplicate unless I leave it for a day or two(which I don't want to do) Anyone else notice this?? Thanks!

[TripleTransAm]

The only thing I get after startup is a click and a slight change in RPM, which sounds like the A/C compressor kicking in.

[RedMM]

If the belt tensioner or ac compressor had a bad bearing, wouldn't this noise happen all the time instead of just after sitting all night?? When starting cold it happens maybe 80% of the time. thanks1

[Agent M79]

I wonder if you are hearing the air bag pump? Sometimes I get that when I let it sit overnight on an uneven surface. It'll run 5 - 10 seconds and make a BRRRRRR type sound.

[RedMM]

Agent M79- No, this is one solid boom/skreech. I know the pump noise that you are referring to and this is different. Thanks!!

[carfixer]

Here is a cut and paste of a message from Ford, see if it applies to you.

15697 NORMAL CONDITION: MOMENTARY GRUNTING SOUND
SOME VEHICLES WITH AIR CONDITIONING UTILIZING R-134A MAY EXHIBIT A MOMENTARY GRUNT/POP AFTER BEING PARKED FOR SOME TIME & THE COMPRESSOR IS ENGAGED BEFORE THE ENGINE COMPARTMENT HAS WARMED UP. THIS IS DUE TO LIQUID R134A BEING PUMPED OUT OF THE COMPRESSOR. R134A WILL TRAVEL TO THE COOLEST POINT (THE COMPRESSOR) ONCE THE ENGINE HAS COOLED, DUE TO THE DIFFERENCE IN TEMP BETWEEN THE ENGINE COMPARTMENT & THE VEHICLE INTERIOR. WHILE MANY VEHICLES HAVE PCM STRATEGIES THAT ADDRESS THIS BY REPEATEDLY CYCLING THE COMP ON START- UP, THIS MAY NOT TOTALLY ELIMINATE IT. REPLACING A/C COMPONENTS WILL NOT ELIMINATE THIS. COMPONENT DURABILITY IS NOT AFFECTED. MINIMIZE THE NOISE BY TURNING THE A/C SYSTEM TO VENT BEFORE EXITING, & IN MILD AMBIENT TEMPS (APPROX. 50-75F) WAITING A FEW MINUTES BEFORE TURNING ON THE A/C OR DEFROST.

[carfixer]

2) and alignment checked due to wandering to the right.

Be sure the service dept has the correct adapters for the alignment heads to prevent wheel damage. Do a search on this here, lots of horror stories. If they say they have them, have your service advisor inspect each wheel together with you BEFORE the alignment is performed and reinspect before you leave.

[Ross]

RedMM, when you shut down your car for the night, do you turn off the AC/Defrost? If you shut it off at night, then it seems that it wouldn't be kicking in the next morning until you turned it back on. You could try turning it off tonight, and then see if the noise is duplicated in the morning. Or is there something I don't know (probably) about the AC that would do this even when turned off?

[RedMM]

Carfixer and Ross- no, I don't turn off ac/heat when parking-I usually just keep it where ever it is set. Thank you very much Carfixer!! I think that excerpt you posted sounds exactly like what is happening! I'm not looking for problems and if this is normal for some vehicles, that is good enough for me. Also a BIG THANK YOU for pointing out the damage some people have had to the wheels during alignment or balancing. I do remember reading some of these stories shortly after joining this site. I will ask about this BEFORE I have them look at alignment as the wheels are 100% perfect now!!! I wonder if this pulling to the right may be normal due to the size of the tires and the way most roads slope to the right. it's not a bad pulling, just enough to be annoying. Carfixer-thank you again-you always have excellent information. I appreciate your help!:D

[RedMM]

Carfixer- I saw your DTR photos. The shine on your car is INCREDIBLE!! I had the dealer do the Ziebart "diamond gloss" paint protection application before I picked the car up. It looks nice, but.........NOT LIKE YOURS!!! How did you get such a fantastic shine??

[TAF]

Originally posted by RedMM
Carfixer- I saw your DTR photos. The shine on your car is INCREDIBLE!! I had the dealer do the Ziebart "diamond gloss" paint protection application before I picked the car up. It looks nice, but.........NOT LIKE YOURS!!! How did you get such a fantastic shine??

You used the WRONG "Z-stuff"...

You need...ZAINO (http://www.zainostore.com/Merchant2/merchant.mvc)

[RedMM]

Hey TAF! thanks for ZEE Link. I will have to try it next spring. Carfixers DTR looks awsome!! I was in your town a couple of weeks ago with a friend who was working a trade show. There must be alot of disposable cash in Atlanta-I've never seen so many Navigators and Aviators!!:)

[KraziKid]

Originally posted by Agent M79
I wonder if you are hearing the air bag pump? Sometimes I get that when I let it sit overnight on an uneven surface. It'll run 5 - 10 seconds and make a BRRRRRR type sound.

I never knew what that was caused by. Thanks for telling me what one of the many wonderful sounds MM's make is :P.

[troopcar]

Same here. Never knew exactly what that sound was. Just knew it had to do with being parked on an uneven surface.

Thanks,
troopcar
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