Noise under Dash driving me nuts!

[alykat06]

I just bought my 08 Ironman edition XLT V8 explorer 3 weeks ago, and after a short weekend trip on our way back we started hearing the most annoying Hissing (more like someone blowing up a balloon or pumping up a tire) sound. Ugh I got rid of my 95 Explorer because it was nickle and diming me lol. I'm dont much about SUVs, so if anyone could simplify what this problem may be I'd be greatful. Sorry if I am posting an old topic.

It does it while accelerating, doesnt matter the speed, after gaining some momentum after pressing the petal it stops, it doesnt matter if the heater is on/off or what temperature it is outside (we had 60 on monday, 30's on tuesday). It also does it for 5-6seconds after I turn the engine off. Its coming from right under the glove box or glove compartment from what I can tell, looked underneath and see 2 black-round/oval objects and wires, but everything seemed tight (then again I couldnt see much since everything was wrapped in electrical tape and hell if I know what I'm doing lol). It seems to be coming from one of those two objects (Idk what they are). If I could pin point the issue, then I have someone who can fix it, but I dont want to waste anyones time or my money diagnosing since it seems that most dealerships dont know what it is. I have seen some posts stating problems such as the valve, loose wires, hoses, battery box issue, or the plastic heater door? what do you guys think it is? Thanks!

 

[bender]

there are numerous threads on this, it is a vacuum issue, I have had mine in a couple of times and the problem continues to come back. Someone had some luck with some electrical tape on a male/female connection under the glove box. mine is sporatic, going away for a few weeks then coming back.

do some searching on "hissing noise" and you'll find some threads.

 

[alykat06]

I have read all if not most of them, some finding the issue, some only temporarily fixing the problem, just wondering if anyone could clarify what parts are located under the dash, if anyone has found the issue, solved it, and it didnt come back. Wish this stupid noise wasnt so annoying lol! and that the darn thing was making this noise before I bought it!

 

[Tanrat]

I have an 08 EB V8 and only makes the noise when I have it on the dual control.Its the heat and AC divider switching between driver and passenger side which is vacuum controlled.I keep it off the dual control and have no noise.

 

[alykat06]

I have an 08 EB V8 and only makes the noise when I have it on the dual control.Its the heat and AC divider switching between driver and passenger side which is vacuum controlled.I keep it off the dual control and have no noise.

Whats dual control? Sorry I don't understand. Do you mean you have a driver's vs passenger AC/Heat control option? Where each person can make their own decision? Mine does not have this option, and I get the noise no matter what position I place the controls in, whether it would be dash and floor, just defrost, etc. Even if ac or heat isn't on.

***Update, as soon as the weather started warming up here in Md and I started using the AC, the noise went away, I had no further issues for 2-3 months, but in the past week, its back! Now what I notice is that when I accelerate, with the ac on, when i reach the peak of accelerating and am about to cruise at a level speed (around 1500 to 2500 rpm), the ac stops blowing air from the front, but its still blowing through the top defrost vents? it only lasts a few seconds before the air comes back through. Any ideas yet now? oh and what is considered normal for the control vent settings for the ac/heat...if it shows floor should air still come through the defrost vents etc?

I took my car back to the "dealers repair shop" before the sound disappeared, and they said it was just a noise and those controls were supposed to be that way. if you ask me they didn't inspect anything but my computer since it never looked like it was touched. They said I didnt have any faults, I could have told them that...I just dropped 385$ at ford for a new spindle, tie rod, abs sensor, and such..so I really want to know what I'm getting myself into.

 

[bender]

yes mine does the same, it coincides with the hissing. the air flow going to the defrost is the default when the system does not have enough vacuum it sends the air to the defroster vents. when enough vacuum builds it reroutes it back to the passenger vents. still no perfect fix, like i said earlier, mine comes and goes as it sounds like yours does.

 

[FordService]

yes mine does the same, it coincides with the hissing. the air flow going to the defrost is the default when the system does not have enough vacuum it sends the air to the defroster vents. when enough vacuum builds it reroutes it back to the passenger vents. still no perfect fix, like i said earlier, mine comes and goes as it sounds like yours does.

It’s unfortunate that you’ve been experiencing an issue like this, especially if it’s intermittent and have had it in for repairs more than once. Have you had your Explorer in the dealer recently? If not, and you would like to schedule an appointment, I’d like to lend a hand. Feel free to message me with your VIN, dealer name, and approximate mileage if you would like any help.

Cory

 

[Davidm53]

Cory should give his thoughts on what the problem is so we all could learn from it.
The main reason I am on this site is to avoid the dealership at all cost.

To bad Cory will not help, since he claims to be a customer rep.

 

[FordService]

Davidm53, the reason why I don’t post my thoughts on issues is because I’m not a technician and I’m not allowed to speculate. That’s why I reach out and request your information. I try to do everything I can to help.

Cory