Strange Gurgling Sound In Exhaust

[inenidok]

well I a 04 gt convertible stang and it's got 116000 miles had the car for 8 months and it use to die at a light when I first bought it well it stopped that after I ran it for awhile. now it gets a strange gurgling sound in the exhaust when you stop it drops rpms to about 200 and picks back up, but you can hit the gas and the sound will go away, and it won't drop idle, it has got now where it use to take a 1/4 of a tank to work it's taking a 1/2 tank to work, I live 72 miles from work, I have no codes no light it's about to drive nuts,

 

[wmburns]

Before digging deeper CONFIRM that the battery and alternator is in tip top shape.

Confirm that the battery holds a charge.

Confirm correct voltage output from the alternator. Test for excessive AC ripple (bad diode).

No excuse to skip these steps as almost all auto parts stores will test for free.

Bottom line. Today's cars simply will not run right without a strong battery and charging system.

I'm assuming the main complaint is regarding the idle quality. Here's some more information on how to start trouble shooting an idle/IAC issue.

http://www.stangnet.com/mustang-forums/resources/troubleshoot-iac-idle-problems-1996-2004.13/

IMO some of this is a chicken and egg problem. IE, are the gurgling noises causing the idle problem or is the noise in response to the low idle (or other real problem).

It would also be a good idea to get caught up on any outstanding maintenance items such as:

• PCV valve
• Fuel filter
• clean MAF
• Spark plugs especially if over 100k miles on a set.
• check for moisture in the spark plug wells.

 

[inenidok]

no not chicken and egg it's taking a tank to go to work and back. I will check voltage but all this computer crap is crap I rather have a carb all day long I can rebuild them. and tune the hell out a carburetor engine.

now don't I have to remove the injectors and fuel rail to change the plugs and coils? and replace them as well.?

but the exhaust sound is like the whole damn exhaust system is about to explode.

 

[Rusty67]

Just because you understand carbs better than fuek injection doesn't make fuel injection suck. You just need to learn about the system you are working on.

If the car is using a ton of gas, ie getting crappy mileage then it is probably got a serious problem with one of the systems. Have you tried pulling codes? Maybe you check engine light bulb is burned out and the might has been trying to tell you something this whole time.

Something is obviously out of whack. Wmburns is the man and he will help you if you let him. Check the stuff he said to check because it is good practice to do anyways.

Can you provide more info on what the exhaust sounds like? Your description is rather vague.

 

[Az Pete]

My 02 dropped in mpg drastically, would not idle, service engine light came and went, and performance varied from one start to the next. I found the rubber hose attached to the pcv valve was collapsing once the car was warmed up. It was not real visable due to the intake tube covering it and it looked good from the top. When cold, the hose was in its natural shape, once warm, it collapsed. Replaced it and all things are better.

 

[inenidok]

I got no codes nothing not a thing in memory, that is the the puzzle it honestly runs like crap, imo I can tell a difference. but what took a 1/4 tank takes a 1/2 tank. it idles good it does, go up and down slowly but not crazy. no I may run sound fine, then as you drive you get that gurgling sound you can hear it and notice it then you come to a stop the rpm will drop to 200 and then pick up drop down now most of the time you can put it in neutral and tap the gas pedal and it will go away most of the time but recently it's getting more and more common and not going away for long

bulb not burned out it burns had a shop check the codes, this thing is driving me nuts

 

[inenidok]

exhaust sound is hard to explain really other then a gurgle.

like wind going over an open bottle,
kid blowing a tune in a open pipe,
like a boat idling in the water with the exhaust in the water

 

[wmburns]

now don't I have to remove the injectors and fuel rail to change the plugs and coils? and replace them as well.?

No. You don't have to remove the injectors and fuel rail to change the plugs.

As a reminder. Those of us out here in Internet land known nothing about your car and the history of it other that what is posted about it.

Nor do we know anything about your abilities other than what has been posted.

Frankly the people asking for help cover the entire range of car experience. Unfortunately I deal with people all the time that can't/won't believe that a symptom such as quitting at a light "could" be caused by something as simple as a bad battery. They stick to the belief that once the motor has started that the battery plays no role in how the motor runs (which is not true).

Frankly your problem "could" be caused by a number of things. Wouldn't you rather rule out the simple stuff first?

Does the check engine light blink while this problem is happening?

 

[inenidok]

yes sir I would like to rule out what it is not but there are no flashing light on other lights comes on nothing just when it makes that exhaust sound you know it's going to act up. if it don't make that sound it runs great, but the sound is more common now and I am lost I have built and restored a bunch of cars nothing computerized. all been 70's and older to me the classics. but I have never heard a exhaust sound like this and this type of problem

 

[wmburns]

Any evidence of gas in the oil?

Consider getting yourself an oil filter cutter and cut open and inspect the oil filter at the next oil change. Look for any metal debris on the filter element. What we are trying to determine is if the timing chains are worn out.

Confirm that the car drives OK and makes good power when the problem is not happening.

Tell us about any other "mods" done to this car.

 

[Rusty67]

Is it possible the brick in his cat has come loose and is blocking exhaust flow in a goofy way? I've heard of this happening and causing all sorts of weird engine issues. Either that or the muffle is hosed up in a strange way. It might explain some of the issues.

 

[inenidok]

Any evidence of gas in the oil?

Consider getting yourself an oil filter cutter and cut open and inspect the oil filter at the next oil change. Look for any metal debris on the filter element. What we are trying to determine is if the timing chains are worn out.

Confirm that the car drives OK and makes good power when the problem is not happening.

Tell us about any other "mods" done to this car.

no mods it's all factory I am 2 owner. it has good power I think I never drove a 4.6 to compare it to. when I get the oil changed I will ask for the filter

 

[wmburns]

I'm trying to think of ways to rule out a timing related issue.

• Check the CKP sensor to see if the hold down bolt is loose or if the CKP sensor is able move around inside the motor.
• Perform a through visual inspection of the crank damper. Look for evidence of cracks or run out. This is a long shot as finding a damper problem on the car is not very likely.
• Check the CAM sensor to see if it's loose. Also check the electrical connector to see if there are any bent/push pins or other damage to the wiring.
• Do you have an ODB2 scanner that is capable of monitoring operational data? If so, would like to know how the PCM reported timing advance is acting.
• Do you smell raw gas?

PCM controlled cars are seriously affected by any electrical instability. Would be handy to know the voltage when this problem occurs. For an intermittent problem one way to monitor voltage is to use an "add a fuse" in the driver's kick panel. This will give a hot pig tail that we can attach a Volt-Ohm meter (VOM) which we can use to accurately monitor buss voltage while driving. I'm interested to know how the voltage changes during this event.

 

[Moosee1955]

Try replacing the idle air control valve. I've read quite a few other posts that had the same gurgling sound, and this seems to be the first step. Also please spend the extra $ and buy one from Ford. Most if not all the aftermarket ones don't work. Keep us posted.


Sent from my iPhone using Tapatalk

 

[Az Pete]

No matter if there are codes or not.....these items everyone is telling you to check could cause the issues without tripping a light. As long as you wait for a light, you will have a poor running car. Open the hood and start some routine checks as suggested.....or spend the bucks for a shop to fix it.

I am an old carb guy myself but we all have to learn. I get tons of info online all the time.

 

[inenidok]

I'm trying to think of ways to rule out a timing related issue.

• Check the CKP sensor to see if the hold down bolt is loose or if the CKP sensor is able move around inside the motor.
• Perform a through visual inspection of the crank damper. Look for evidence of cracks or run out. This is a long shot as finding a damper problem on the car is not very likely.
• Check the CAM sensor to see if it's loose. Also check the electrical connector to see if there are any bent/push pins or other damage to the wiring.
• Do you have an ODB2 scanner that is capable of monitoring operational data? If so, would like to know how the PCM reported timing advance is acting.
• Do you smell raw gas?

PCM controlled cars are seriously affected by any electrical instability. Would be handy to know the voltage when this problem occurs. For an intermittent problem one way to monitor voltage is to use an "add a fuse" in the driver's kick panel. This will give a hot pig tail that we can attach a Volt-Ohm meter (VOM) which we can use to accurately monitor buss voltage while driving. I'm interested to know how the voltage changes during this event.

I will get the volt ohms meter out I don't have obd2 tool, I have checked for vacuum leaks the other day check for loose wires and hoses and found none

 

[inenidok]

I thought about iac but it's a 100 plus dollar part for motorcraft. but then I will be back to spending unnecessary money at some thing that's not the problem. that's like a friend had a chevy car we replaced every single part the computer was saying was bad never fixed the problem took it to the dealer come to find out the computer was bad so the 1000 plus dollars he spent was unnecessary

 

[wmburns]

In the trouble shooting link provided there were several "free" functional and trouble shooting tests that were called out.

The brand "X" IAC is half the price of the Ford unit. I have had good luck with the non-Ford units. I'm not so sure that the people with that have had a bad experience have also had other "issues" to deal with like excessive PCV blow by which really gums up an IAC.

Speaking of free items, this should be an IAC without a black vent. These can be cleaned. Which for someone concerned with $$, the cleaning is a good idea for no other reason than to find out IF it changes the symptom at all.

http://www.oreillyauto.com/site/c/detail/BWD0/31077/02169.oap?year=2004&make=Ford&model=Mustang&vi=1425024&ck=Search_idle+air+control+valve!s!motor_1425024_499&keyword=idle+air+control+valve!s!motor

 

[inenidok]

going to try to clean it today before I go to work this evening in hope it's the problem

 

[inenidok]

took off iac it's new cleaned it anyways but got weird sound engine now might be looking for 5.4