Mustang Bullitt Forum banner
1 - 20 of 82 Posts

·
Registered
Joined
·
596 Posts
Discussion Starter · #1 ·
I Have now heard the 3500 RPM death rattle today while merging with traffic with a cold engine. I was hoping I would not be affected by this problem. I dont drive the Bullitt hard when cold usally shifting before 2800 RPM. But today I had to make a quick run and traffic was heavy so I had to smash the go pedal, 1st gear 3500 and there it was. I tried to duplicate the sound while parked and could not get it to do it. I'm so bummed!
 

·
Registered
Joined
·
394 Posts
It will not make the noise unless there is a slight load. I don't know why but, I have verified this on several occasions. I have tried to get the car to make the noise in my driveway with no success. It also doesn't seem to make the noise under WOT acceleration. For me it only does it under partial throttle between 3200-3600 rpm. First noticed it with about 1000 miles on the odometer.

BTW- I like the "death rattle" descritpion.

Eric
 

·
Registered
Joined
·
596 Posts
Discussion Starter · #3 ·
I have 2500 on the clock, but like I said I don't get in that RPM range normally when the engine is cold so it may have had the problem long before now. Really bummed out about this problem reaching out and grabbing my Bullitt.


_________________
True Blue Bullitt Driver

<font size=-1>[ This Message was edited by: Bullitt4075 on 2002-01-08 19:59 ]</font>

<font size=-1>[ This Message was edited by: Bullitt4075 on 2002-01-08 20:00 ]</font>
 

·
Registered
Joined
·
198 Posts
<TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font size=-1>Quote:</font><HR></TD></TR><TR><TD><FONT SIZE=-1><BLOCKQUOTE>
On 2002-01-08 19:41, Bullitt4075 wrote:
I Have now heard the 3500 RPM death rattle today while merging with traffic with a cold engine. I dont drive the Bullitt hard when cold usally shifting before 2800 RPM. But today I had to smash the go pedal, 1st gear 3500 and there it was. I tried to duplicate the sound while parked and could not get it to do it. I'm so bummed!
</BLOCKQUOTE></FONT></TD></TR><TR><TD><HR></TD></TR></TABLE>

Not to make light but this is more evidence of my hypothesis that not everyone has this problem because they haven't operated the car in the necessary fashion to hear the noise.

Anyway, yes it's load dependent.

Try this: next time you fire the car up cold go up to the 3k rpm and listen for the noise and then, WITH YOUR FOOT STILL ON THE GAS, push the clutch pedal in(disengaging the clutch).

i bet the noise goes away (as it did for me).

you're taking all possible load off the motor.
 

·
Registered
Joined
·
2,024 Posts
Fixer

DO NOT think it is piston slap. I know what piston slap is from one of my race engines

<font size=-1>[ This Message was edited by: Bullitt4995 on 2002-01-09 12:10 ]</font>

<font size=-1>[ This Message was edited by: Bullitt4995 on 2003-12-04 21:03 ]</font>
 

·
Registered
Joined
·
198 Posts
interesting. maybe i was lucky...

see what i mean though? kinda hard to swallow the piston slap explanation...

I do have piston slap. no joke. i heard it from the very beginning. its funny cause i hear the piston slap just before the rapping sound so its a good caomparison. The two sound way different.
 

·
Registered
Joined
·
1,428 Posts
Yep, I have it also. I believe all 4.6s will do this as my 99 E-150 Van also did it when the engine was cold, but went away when it warmed up. I would think that we should'nt be too alarmed.
 

·
Registered
Joined
·
302 Posts
I was going to ask if anyone had checked to see if other cars that use the 4.6 are experiencing the same problem. ie crown vic, gm, towncar, etc.
 

·
Registered
Joined
·
198 Posts
THE F-150 *i think* does make the noise, but from looking through the various f-series web sites its very small percentage and many of the people think its piston slap. I have heard of at least two expedition and one f-150 owner complaing of the exact same symptoms.

I looked through a crwon Vic forum and found nothing.
 

·
Registered
Joined
·
131 Posts
It sounds like I too HAD this same noise so I took it to the dealer. It only happened after sitting over night and the engine was cold. Here it doesn't get cold so the mornings were the only time I could produce the noise. The dealer replaced a part which is on the air intake right in the front. Looks like a small silver cylinder. On my job order its called a "VALVE ASSEMBLY-THROTTLE" Part Number SPO 2R3Z 9F715 DA. I had it replaced in November and since then the noise hasn't returned. I'm not an engine guy but you might want to check this out.

_________________
pgrtag
Bullitt #5082


<font size=-1>[ This Message was edited by: pgrtag on 2002-01-13 17:54 ]</font>
 

·
Registered
Joined
·
198 Posts
<TABLE BORDER=0 ALIGN=CENTER WIDTH=85%><TR><TD><font size=-1>Quote:</font><HR></TD></TR><TR><TD><FONT SIZE=-1><BLOCKQUOTE>
On 2002-01-13 17:29, Bullitt4995 wrote:
GREAT! And I switched from GM to go through all this aggrevation? :sad:
</BLOCKQUOTE></FONT></TD></TR><TR><TD><HR></TD></TR></TABLE>

Toyota has a few problems with this sort of issue as well so greener grass is not too easily found.
 

·
Registered
Joined
·
41 Posts
here is some information that might help you located the noises for your self, this is going to be a cut and paste, happy hunting and wish you luck...
******************************

First thing you need to do is spend 20 bucks for a cheap stethoscope at the auto parts store or if you are going to do this a lot get the electronic ones from Steelman for about $160.

But, possessing human nature, you will convince yourself that a hose stuck in your uneducated ear will do just as well. No sense in arguing with you that the whole idea is to be able to discern infinitesimal changes in direction and intensity that require the use of two somewhat experienced ears AND the right tools.

So stick your dumb ol' hose in your stupid ol' ear and we'll start with some clues.

Remember that diagnosis of engine noises is nothing more than splitting possibilities down to only one

First off, eliminate all of the accessories like the alternator, power steering pump, A. C. compressor and vacuum pump by removing the belts one at a time. If the noise is gone, of course the problem is a belt driven accessory. If the naughty noise is still there you should be able to hear it more clearly by not having the accessories whirring away.

If the engine has a carburetor instead of fuel injection it probably has a mechanical fuel pump mounted to the engine. Before the engine gets too hot, put your hand on it. If it is making a noise you should be able to feel it.

Try to track the noise down with the stethoscope tip or the end of the hose suckered onto the engine surface, sealing the end. Spend a full ten minutes putting the hose all over the engine, not just where it is loudest. Try to envision the parts moving inside the engine. You are training your ear, not just listening, so don't get in a big rush except to be sure that the engine doesn't overheat. A trained ear can tell you which piston is slapping or which rocker arm is clacking from outside the engine so if you come out from under the car proudly saying, "it's the bottom end" get your dumb-ass back under there until you can tell me it's coming from the oil pump or the 3rd piston back on the driver's side or the flywheel or the camshaft.

Rod knocks are loudest at higher speeds (over 2500 RPM) Feathering the gas pedal may result in a distinctive back rattle between 2500 and 3500 RPMs.

Bad rod knocks may double knock if enough rod bearing material has been worn away allowing the piston to whack the cylinder head in addition to the big end of the connecting rod banging on the crankshaft rod journal. It will sound like a hard metallic knock (rod) with an alternating and somewhat muffled aluminum (piston) klock sound.

Wrist pin knock in modern engines is very rare today but is a favorite for the misdiagnosticians.

Determining which cylinder contains the noisy parts may be aided by shorting out the plug wires one by one with a common low voltage test light. Now you won't get the bulb to light up but it is a convenient way to short the cylinders without getting zapped or damaging the ignition coil.


Attach the alligator clip to a convenient ground, away from fuel system components, and pierce the wire boots at the coilpack or distributor end of the wire.


If the noise is changed when the plug wire is shorted to ground, you can figure that the problem is in the reciprocating bottom end parts. (piston, wrist pin, connecting rod or connecting rod bearing)


The reason the sound changes is that when you short the cylinder plug wire you are stopping the combustion chamber explosions that are slamming the piston downward making the inside of the big end of the connecting rod bang against it's connecting rod journal. Or in the case of piston slap, no explosion changes how the piston is shoved hard sideways against the cylinder wall.

If you get a change in the sound when you short a cylinder out it may become moot as to what the problem is because the oil pan and cylinder head must be removed to correct the problem. [Generally speaking, an engine with damage to reciprocating parts (pistons, rings, connecting rods, wrist pins or rod bearings) and more than 70 thousand miles is not cost effective or risk free enough to attempt to repair. Replacing a crankshaft, for example while the rest of the engine has 70k perfectly maintained miles on it is risky enough but whatever killed the crank has scored the rings and packed the lifters with debris and smoked the piston pin bosses etc.]

If the sound doesn't change, look at parts other than the reciprocating ones. In many cases of rod-knock or piston slap, more than one is banging so even if you eliminate the noise from one rod the other one will still be a-banging away with a different, more singular tone.

When the engine is cold, the aluminum piston is small in comparison to it's iron cylinder. Therefore the rather hollow slapping noise will be loudest first thing in the morning. After the engine warms up, the aluminum piston heats up faster than it's iron cylinder, cutting down on the excessive clearance between the piston and cylinder wall.

So, the test is this:

First thing in the morning, start the engine up and run it for 15 seconds while you listen carefully and memorize the sound and it's intensity. Shut it down quickly, pull the spark plugs and put two squirts of motor oil into each cylinder. Reinstall the plugs, fire the engine up again and listen.

If you have piston slap the noise will have been greatly reduced or even eliminated…..for 15 or 20 seconds that is, and then your nightmare noise will come back like a Marine Corps marching band coming toward you in the parade.

*************************************
Diagnose Noises with a timing light?

Valve train noises occur at half of crankshaft speed so even if your ear can't tell whether the noise is happening at 700 rpm (raps per minute) or only 350 rpm, your eyes can. Hook the timing light to any one cylinder and watch the flash illuminate the timing mark. Stare at it for a while and see if the flash jives with the knock. If it does, then it is more likely to be rocker arms, pushrods, lifters, camshaft, cam bearings, timing chain and gears. If the noise seems twice as fast it is probably in the crank, mains, rods, rod bearings, wristpins and pistons.


well people, i hope this helps.

bob in jville, fl.
Member STLE
Lubricant Specialist
http://www.bobistheoilguy.com
 

·
Registered
Joined
·
337 Posts
Bob,

Thanks for the info. The challenge with this noise is it pretty much only occurs while driving, under load. Thus a stethoscope can't be used.

I was able to mic the engine bay with two small electret mics and record the engine in stereo (for a binaural recording, allowing sounds to be placed in 3D while wearing headphones). The day I performed this test the engine did not make the noise (I had just switched to 91 octane fuel, and did the test later in the day, so temps were higher). Perhaps when I have some free time I'll get all the gear together again and record the engine first thing on a Saturday morning.

pgrtag,

Did your sound only occur while under load around 2500-4000 RPMs?

<font size=-1>[ This Message was edited by: DrivingSimulators on 2002-01-13 20:01 ]</font>
 

·
Registered
Joined
·
131 Posts
Yes my noise did happen in that range. I thought at first it was suspension because it sounded like it was coming from under the car but the dealership said that the noise resonates through the car so it would sound like that.

_________________
pgrtag
Bullitt #5082


<font size=-1>[ This Message was edited by: pgrtag on 2002-01-13 23:11 ]</font>
 

·
Registered
Joined
·
596 Posts
Discussion Starter · #16 ·
Does anyone know if Mr. T has ever said anything about our engine noise?????? Maybe on another thread.
 

·
Registered
Joined
·
193 Posts
"The dealer replaced a part which is on the air intake right in the front. Looks like a small silver cylinder. On my job order its called a "VALVE ASSEMBLY-THROTTLE" Part Number SPO 2R3Z 9F715 DA. I had it replaced in November and since then the noise hasn't returned."

I just reviewed the above post, has anyone else checked this out and had any luck? If so, how did it turn out?

Dave
 

·
Registered
Joined
·
117 Posts
You had the infamous rattle/tick at 2500-3000 rpm and this got rid of the noise ??? Do we have a cure guys or is this a different noise and a different fix?
 

·
Registered
Joined
·
596 Posts
Discussion Starter · #19 ·
Bullitt00155, are you sure you had the death rattle (when cold) and this fixed it? Man that would be awesome if it is. This problem has been bugging a lot of members. Could you double check with your dealer to see that indeed this was the fix. We will be keeping our fingers crossed.
 

·
Registered
Joined
·
34 Posts
That silver cylinder that they replaced for you is the IAC (Idle Air Control) valve. I can't see how that would fix the "rattle" though??
 
1 - 20 of 82 Posts
Top