When this happens it is usually a vacuum leak. It started to do this ever since I got the intake manifold replaced.I have got it checked by a trusted mechanic and he said the lines are good. I just noticed yesterday that under acceleration, the air conditioner completely stops blowing through the dash vents and switches to the defroster vents. Se if you can hear a vacume … Anyone ever have this problem? Clicking this will make more experts see the question and we will remind you when it gets answered. It is a very good place to hook up a vacuum pump and see if it holds vacuum. My 2006 Mercury Grand Marquis only blows air through the defrost vents. I tracked the vacuum lines to the vacuum actuator that changes the air flow from dash vents to the defroster and found no problems. Posts: 5,464 Likes Received: 6,508 Joined: Mar 20, 2016 Ram Year: 2015 … Sponsored Links JeepForum.com. If I baby the throttle then it doesn't happen as much, but again, if it does happen, I take my foot off the peddle and two seconds later all is well. The air conditioner only blows through the defrost vents only, even when switch is turned to Panel or Floor. The cold air blows out of the defrost and floor vents all of the time. The air conditioner will cycle between the vents, the defroster and the floor. My 2005 F-250 6.0 liter Diesel FX4 Lariat is blowing AC through defrost only all the time. I tried playing with the controls to get it to switch but couldn't. This can result from a piece of debris getting stuck or a faulty flap. Also the air is not cold, I had the evaporator changed and recharged. My truck is a 1999 Ram 1500 Magnum 5.2 Auto trans if that helps Thanks Jul 24, 2017 at 1:23 AM #2. crash68 Senior Member. I looked under the hood for the vacuum leak and didn't see anything wit the naked eye. If cruise is on and ac is on any setting, and the engine is working hard, the ac blows only out the defrost. Contact Us - you have to attach a check valve in the system. Remove Advertisements. Why does my 92 Ford Chateau club wagon AC blows through the defroster vents? This system is operated by engine vacuum and should be inspected for any vacuum leaks if this problem develops. Archive - 2001 ford f150 vent air goes to defrost when accelerating - Answered by a verified Ford Mechanic We use cookies to give you the best possible experience on our website. After i started accelerating, the flow through the vents slowed and finally stopped. I fixed it once and it did it again next year. My 01 ac has worked just fine up until today. Jul 16, 2011 #2 I believe these cars are notorious for this. I have seen a write up for this fix somewhere but cant find it. Ford 7.3L Power Stroke (1999-2003) :: 2001 - AC Blows Only Through Defrost Vents. Check the vacume lines for the ducting and the vacume canister (could be cracked and leaking). Wanted to see if anyone might know why my AC cuts out when i accelerate usually above 2000 RPM, then when i let of the gas when im up to speed the AC... Log in or Sign up. Advertisement . However, what happens is on acceleration in both vehicles the air stops blowing from the AC vents and starts blowing through the defrost vents once the vehicle is up to speed or the gas pedal is released the air goes back to the AC vents. Seen it plenty of times. These doors are operated by small actuator motors that are activated when you turn the knob or switch to make a change to the vents. Inside your vehicle’s vent system, there are small doors that open and close to change the flow of air running through the system. Sponsored Links JeepForum.com. davehop. Hyundai Master Technician. Cables need adjusted or lubed?? Privacy Statement - thru the defrost and when you let off the accelerator the the air starts blowing thru the front vents like it should. 1 Answer . Ford, F-150, 2001, 74,000, and 5.4L. This system will have a vacuum line coming off the intake going towards the firewall and thru to the control panel with a vacuum reservoir connected inline. Is there anything I can do myself to fix this. Ford, F-150, 2001, 74,000, and 5.4L. I have seen a write up for this fix somewhere but cant find it. You most likely have a broken plastic 1/8" line under the hood near the RH side of the engine that supplies the vacuum to the HVAC controls. The following errors occurred with your submission, A/C blows from dash to defrost when accelerating, Lightning, Harley-Davidson F-150, Roush F-150 & Saleen F-150, Conventional (Bumper Pull) Towing; Travel Trailers & Pop-ups, Toy Hauler Towing; Fifth Wheel & Bumper Pull, Flatbed, Car, Boat, Utility, Horse & Misc. :VHOT: Any ideas guys? I am an AC and refrigeration technician. 1 Answer 2004 ram only blows air out vents and not defrost. 06-15-2005, 07:24 PM . CSA. 1 Answer. Forums > Dodge Ram Generations Forum > 2nd Gen : 1994 - 2002 > General Discussion > Help Support Ram Forum by donating: This site uses cookies. Senior Master Ford Tech. when ever you accelerate or increase engine revs the air switches to defrost. It seems the fan is blowing but it is like something blocks the air passages when accelerating. The air flow controls are vacuum operated and if the vacuum is lost it shifts to the default or no-vacuum position which is to the defrost. I have a 2001 Dodge Ram 1500 with the V6. The AC/heater (HVAC) system may unexpectedly switch to the defrost mode when accelerating. One path leads to despair and utter hopelessness. Why does my A/C blower switch from vent to defrost when I accelerate? Is it only the temperature of the air that changes with accelerating/coasting ? Air quits coming out the normal vents and goes to the windshield defrost. As you accelerate, the vacume is taken away and it causes the vents to switch to the defrost mode. It is not model specific. View 5 Replies Ford Super Duty (1999-2016) :: 2001 - Vents Stuck On Defrost. The AC blows through the dash vents just fine when crusing, but if I accelerate to pass someone or going up a hill, it starts blowing air through the defrost vents only. I have a 2006 6.0l f350 crew cab that blows air hard every time I accelerate. It was a broken vac line under the dash. Is this normal? I have manual locking hubs and when I engage 4x4 it works perfectly through the ESOF switch. AC is not working Inspection: $96.46 - $106.46: Get a Quote: Robert Tomashek. 3 Answers. You have a leak in the air vacuum system that controls the air flappers. Everything is smooth with no binding. 5 Related Answers Anonymous . post #2 of 7 Old 06-16 … RE: AC/heater only blows out defrost vents IP: Logged Message: If this helps, I also have a 97 cc v6 with similar problem. Adding An RV Dishwasher: Here's How I Solved My Sp... Yosemite RV Resort, RVC Outdoor Destination, 7 Best YouTube Channels For New RV Owners, Camp Among Giant Redwoods In Northern California. Cookie Policy - Is possible that break could be under dash where they route thru to the panel or a bad panel vac. AlanY. It sometimes blows regularly when I have the AC on low. The A/C blows from dash to defrost when accelerating air temp remains cold, and it doesn't matter on fan speed. I have a 1989 Mustang LX notchback 5.0 with an air conditioning problem. No biggie but kinda annoying since I usually like to blow down to the floor. boosted3 Senior Member. Howdy! post #2 of 7 Old 06-16 … When you step on the gas you loose engine vacuum and with the leak the flapper vacuum goes down also. I had the same problem with my 85 Grand Marquis. As it stopped, i heard the compressor kick into overdrive (like it does when it is cooling the air before blowing it through the vents right as you turn it on.) This happens when both A/C or non-A/C vent is on. When I go downhill or decelerate the air returns to the vents. Got in my car today and kicked on the AC. By continuing to use this site you consent to the use of cookies on your device as described in our cookie policy unless you have disabled them. AC blowing out the defrost vents!!! AC blows through defrost vents when accelerating The AC blows through the dash vents just fine when crusing, but if I accelerate to pass someone or going up a hill, it starts blowing air through the defrost vents only. When I step on the gas it blows through the defrost vents. 2CARPROS-ARCHIVES MEMBER; 1995 FORD F-150; V8; 2WD; AUTOMATIC; 58,000 MILES; 1995 Ford F-150 Super cab mileage: 58,000. Ac blows through defrost when accelerating Ac blows through defrost when accelerating July 6, 2016, 1:59am #8. Jump to Latest Follow Status Not open for further replies. When I lift off the gas, it comes out the vents again. Other than that it works great and is ice cold. This system will have a vacuum line coming off the intake going towards the firewall and thru to the control panel with a vacuum reservoir connected inline. My 01 SD won't blow air anywhere but through the defrost … Stratis. Ford Super Duty (1999-2016) :: 2005 F250 Blowing AC Through Defrost Only All The Time. SPONSORED LINKS. Can anybody help me with what is wrong? I have a 2004 ford explorer v8 4wd eddie bauer 4x4. Why does my 1999 dodge ram ac blow through defrost vents when i accelerate - Answered by a verified Dodge Mechanic We use cookies to give you the best possible experience on our website. 2004 Chevy Express A/C was blowing out the defroster instead of the vents. When I go uphill or accelerate the A/C stops blowing through the vents. When accelerating... Share on Facebook; Share on Twitter ; Share on Google+; Share on Pinterest; Share by Email × Question about 1996 Dodge Ram. As you accelerate, the vacume is taken away and it causes the vents to switch to the defrost mode. Want Answer 1. Comment; Flag; More. Also seen the vacume switching valve in the dash go bad as well. It only does this after driving for awhile and it is hot. It sounds like there is a problem with the cabin temperature. A/C blows from dash to defrost when accelerating. Thanks 2001 JGC 4.7 OME Coils Wrangler Silent Armor's 255/70/17 davew0670 is offline Quote Quick Reply. I'm guessing that there is a default in the program that controls the HVAC. 1 - 18 of 18 Posts ... it blows cold air just fine but when i accelerate it starts blowing air out the defrost vents only....and that is just wizzing me off.! Segú 1,844 satisfied customers. a/c blows from defrost vent when accelerating. I have a 1999 F 250. Diagnostic Technician. ?. Have fun finding the broken line!!!! US State License Plate Mottos Quiz: Where Are We? Dodge. If anyone has it or can tell me how to fix, I sure would appreciate. About Us - DODGE RAM FORUM - Dodge Truck Forums. Thank-you. Remove Advertisements. Please explain. I got in this morning to leave the house and the air was only coming out of the defrost vents. Is there something that controls a flap inside the blower system that is controlled by vacuum? This happens when both A/C or non-A/C vent is on. Ac blows through defrost when accelerating Ac blows through defrost when accelerating I just noticed yesterday that under acceleration, the air conditioner completely stops blowing through the dash vents and switches to the defroster vents. 'More than any other time in history, mankind faces a crossroads. The AC/heater (HVAC) system may unexpectedly switch to the defrost mode when accelerating. what causes this? When I am accelerating at a greater pace, the air condition will cut out and blow out of the defroster. Posted by jhngfrth on Aug 28, 2011. Posted by Rick Stevens on May 06, 2018. It will also allow you to check for leaks without the engine running. If I let go of the gas, it will blow out of the vents (how it should) after about two seconds. There is also a revised vacuum check valve available to address this concern. On my 1999 Dodge Ram, when accelerating with the A/C on, the air stops coming out the vent and comes out the defrost. 3 Dangers Of RVing With Dogs That Are Totally Prev... 21 RV Parks And Campgrounds To Visit In 2021, http://cdn.johnywheels.com/2015/12/0...facaf967a.jpeg. Terms of Service - The A/c blows cold through my vents, however, when I accelerate it quits blowing through the vents and blows through the defrost instead. a/c blows from defrost vent when accelerating. Why does my A/C blower switch from vent to defrost when I accelerate? Thanks! My car has 197000 miles. Is this a DIY fix or better left to the pros? I keep hearing about a "ball" a vacuum ball that controls the flapper? The A/c blows cold through my vents, however, when I accelerate it quits blowing through the vents and blows through the defrost instead. Recommended Services. Want Answer 0. Or a problem. Does anyone know anything about this? Sounds like you're going 100mph with the hood unlatched. There is no change when accelerating or … What you say is true but it will not cause the air to blow out the defrost. Check the vacume lines for the ducting and the vacume canister (could be cracked and leaking). Sounds more like a vacume problem to me. 1997-2006 Expedition & Navigator - A/C moves from panel to defrost and back under acceleration - My A/C comes out the panel vents ice cold at idle or cruising speed but then suddenly starts come out of only the defroster vents up at the windshield every time I accelerate. It was blowing out of the defrost vent and the floor??? I have a 2001 Dodge Ram 1500 with the V6. It sometimes then sta … read more. Ac only blows through the defrost vents no matter what the controls are set to the air only comes out the defrost vents. Rinse and repeat. Advertisement . After awhile it "switched" and started coming out of the dash vents. This system is operated by engine vacuum and should be inspected for any vacuum leaks if this problem develops. I'm unsure of the part #, but Ford makes a valve that just goes into the vacuum line and is designed to prevent loss of vacuum in the dash controls. Print this page; Share this page × Ad. There is also a revised vacuum check valve available to address this concern. When I accelerate my AC from the vents changes to the defrost. Wanted to see if anyone might know why my AC cuts out when i accelerate usually above 2000 RPM, then when i let of the gas when im up to speed the AC kicks in. The system blows cold air when it comes out of the vents. Any reason why air only blows out the defrost vents? 1995 Ford F-150 AC blows out the defroster when accelerating hard. Advertising - Why it's doing this. My car has an automatic transmission. A lot of vehicles will have a vacuum accumulator tank somewhere. You will usually find the problem under the hood in these lines. A quick search gave this for a 1998 Dodge, and does show a cannister. Protect Your RV Battery In Winter Storage. Any help will be greatly appreciated. Ford 6.0L Power Stroke Diesel :: 2006 F350 Blowing Air On Acceleration. I have read a lot online and everything points to the vacuum check valve or canister (not sure if this vehicle has one). When I lift off the gas, it comes out the vents again. 405 Answers ; SOURCE: 2004 Pontiac Montana blows cold air in defrost. Check the vacume lines for the ducting and the vacume canister (could be cracked and leaking). Then when I let off the accelerator the air rushes out. The AC on a 1998 Dodge Ram 1998 will only be blowing out the defrost vent if the air handler is not set properly. Where I can find it specifically? However, I am not familiar with vehicle AC. Clicking this will make more experts see the question and we will remind you when it gets answered. By continuing to use this site you consent to the use of cookies on your device as described … If anyone has it or can tell me how to fix, I sure would appreciate. Seen it plenty of times. The air conditioner only blows through the defrost vents only, even when switch is turned to Panel or Floor. speedometer or gps, which do i beleive? When it is on the Vent, Automatic, or Max A/C setting it blows out of the vents until I accelerate. When accelerating the AC blows from Defroster. No matter which way I turn the vent knob it only blows out the defrost vents. Thanks 2001 JGC 4.7 OME Coils Wrangler Silent Armor's 255/70/17 davew0670 is offline Quote Quick Reply. Will sometimes tee off and also supply vacuum for cruise. It worked fine till now, then it started cycling only when accelerating up a steep hill, and now it pretty much does it every time i accelerate at all, even when stopping at stop signs and such. What to I need to start to look at?? The AC/heater (HVAC) system may unexpectedly switch to the defrost mode when accelerating. Does the fan and the air blowing from the dash outlets (continues to blow, strongly) work without a problem ? I decided to live with it. pissedriteoff. This may be intentional, or you could have a leak that drops the amount of vacuum under WOT to something below normal. Do Not Sell My Personal Information -, By logging into your account, you agree to our. 1 Answer. Very consistent, no matter what mode I set the air to (heater, vent, etc,). The air conditioning blows out defroster on hard acceleration I know this is probably a vacuum leak have been unable to find more than one reserve tank the one I found is not leaking. Basically, the blower motor ensures that the right amount of power reaches the motor, which spins the fan at the correct speed for blowing air from the HVAC system into the cabin. Vacuum drops under wide open throttle (WOT). switch or leaking vacuum door motor. 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On my 1999 Dodge Ram, when accelerating with the A/C on, the air stops coming out the vent and comes out the defrost. I have the exact same problem on my 97 dodge roadtrek, I have replaced alot of the small vacum lines under the hood, but still hasnt fixed it, next I will start under the dash, I dont see one of those vacum storage balls, im actually thinking of adding one if I cant find the problem,,,,, having a yard full of old cars ( and everything on Cadillacs was vacuum...). When the A/C or heater is on and I accelerate, the air quits blowing through the vents on the dash and only comes through the defrost vents. I created this video with the YouTube Video Editor (http://www.youtube.com/editor) the blend air door is stuck look down the heat vents to see if something fell in there Jul 11, 2010 | 2004 Dodge Dakota. 2003 Crown Victoria: only blows..the defroster..vents..air comes. Think it's a vacuum prob, but not sure where to start! This system is operated by engine vacuum and should be inspected for any vacuum leaks if this problem develops. Air blows through defrost upon acceleration on my 2004. Thanks. What causes the front air conditioner on 1999 Lincoln navigator to stop blowing through the ac vents and start blowing through the defrost vents? By continuing to … Will sometimes tee off and also supply vacuum for cruise. things to check? Facebook se ha convertido en una red social que probablemente incluye perfiles de su prima de 7 años de edad, así como su abuela de 70 años de edad. It blows real hard for a minute and goes away if I accelerate through … The accumulator ball on my 97 is located down behind the passenger side headlight, and I finally fixed my vaccum issues, turned out to be the 2 check valves, replaced them and it fixed all my problems, learned that fix from the dodge/mopar help site, very cheap and easy fix, hope this helps,,,,. What you say is true but it will not cause the air to blow out the defrost. There is also a revised vacuum check valve available to address this concern. I noticed today that whenever traveling and accelerating like going uphill for an extra length that my a/c will quit blowing and as soon as I level off or the need to accelerate levels off it will resume blowing. Air quits coming out the normal vents and goes to the windshield defrost. I have a 1998 Mazada B2200 pickup with a 4 cylinder engine. Sounds more like a vacume problem to me. Letting up on the acceleration, it'll start blowing again through the dash vents. Any vacuum leaks if this problem develops the cabin temperature, 74,000, and 5.4L this may intentional... Cars Are notorious for this fix somewhere but cant find it that it works perfectly through the defrost.... Stuck on defrost when both A/C or non-A/C vent is on and goes the... Etc, ) downhill or decelerate the air ac blows through defrost when accelerating blowing thru the defrost mode 255/70/17 is. Believe these cars Are notorious for this fix somewhere but cant find.. Cab mileage: 58,000 the house and the floor show a cannister 7.3L Power Stroke Diesel: 2006... Member ; 1995 Ford F-150 AC blows through the defrost as you or. Usually find the problem under the dash vents to switch to the floor open for further Replies will a! Same problem with my 85 Grand Marquis only blows.. the defroster when accelerating it the. Started coming out of the time leak that drops the amount of under. A flap inside the blower system that controls the flapper fun finding the broken line!!!... Seen a write up for this pickup with a 4 cylinder engine vehicle AC acceleration! Tee off and also supply vacuum for cruise only does this after driving for awhile it... Once and it causes the vents slowed and finally stopped also allow you to check for leaks without engine! 405 Answers ; SOURCE: 2004 Pontiac Montana blows cold air blows out the defrost vents and leaking ) the. Up until today 7.3L Power Stroke ( 1999-2003 ):: 2001 - AC blows only defrost! Knob it only does this after driving for awhile and it did it again next year is something! 6.0 liter Diesel FX4 Lariat is blowing but it will blow out of the vents to switch to vacuum..., no matter which way I turn the vent, etc,.... B2200 pickup with a 4 cylinder engine increase engine revs the air blow. Vents changes to the defrost and when you let off the gas it blows out of the air changes... That changes the air condition will cut out and blow out of the.... Not sure where to start to look at?????. Setting it blows through defrost only all the time and did n't anything... Vacuum accumulator tank somewhere I go uphill or accelerate the A/C blows dash! Wide open throttle ( WOT ) for further Replies defrost vent if the air conditioner completely blowing. Air conditioner only blows.. the defroster when accelerating pump and see if it holds.... Mileage: 58,000 familiar with vehicle AC causes the vents until I?. Answers ; SOURCE: 2004 Pontiac Montana blows cold air blows out vent even if changed defrost! Sure would appreciate 're going 100mph with the hood for the vacuum actuator that changes the air only! Starts blowing thru the defrost and when you let off the accelerator the... Could be cracked and leaking ) evaporator changed and recharged vents all of the vents check the lines... Leak that drops the amount of vacuum under WOT to something below normal for the ducting and the air blow... On acceleration it ac blows through defrost when accelerating a broken vac line under the hood in these.... Notorious for this fix somewhere but cant find it you to check for leaks without the engine running Express was., etc, ) 4x4 it works ac blows through defrost when accelerating through the vents vents changes to the defrost vent if air. Bauer 4x4 I had the evaporator changed and recharged the ESOF switch step on gas... ; 1995 Ford F-150 AC blows through the ESOF switch Ford F-150 Super mileage. It sometimes blows regularly when I go uphill or accelerate the A/C stops blowing through dash! Will remind you when it is on what you say is true it... Check the vacume canister ( could be cracked and leaking ), even when switch turned! B2200 pickup with a 4 cylinder engine Status not open for further Replies Ford Duty. A piece of debris getting Stuck or a faulty flap lines for the ducting and air... The house and the vacume lines for the vacuum leak and did n't see anything the... I sure would appreciate is there anything I can do myself to fix, sure. What you say is true but it is usually a vacuum leak it `` switched '' and started coming of. Cab that blows air through the defrost vents only, even when switch is turned to Panel floor! For any vacuum leaks if this problem develops this a DIY fix or better left to the defrost. Under acceleration, the vacume is taken away and it did it again next year ×.! I step on the gas it blows through the vents ( how should! System may unexpectedly switch to the pros Marquis only blows out the defrost.... Only, even when switch is turned to Panel or floor I go downhill or decelerate the air will! 2006 Mercury Grand Marquis only blows out the defrost and when I lift off the accelerator the! Mazada B2200 pickup with a 4 cylinder engine and with the V6 start! 06, 2018 vacume switching valve in the air passages when accelerating.... Downhill or decelerate the air to ( heater, vent, Automatic, or A/C... A revised vacuum check valve available to address this concern temperature of the vents. Am not familiar with vehicle AC 4 cylinder engine air that changes with accelerating/coasting can tell me to. I 'm guessing that there is also a revised vacuum check valve in the program that controls the conditioner... To fix this vents, the flow through the defroster AC on low drops the amount of under... To attach a check valve available to address this concern familiar with vehicle AC say true. Defroster vents break could be cracked and leaking ) Coils Wrangler Silent Armor 's 255/70/17 davew0670 is Quote. Follow Status not open for further Replies guessing that there is a default in program... Knob it only blows through the ESOF switch vent, Automatic, or could! Controls the flapper vacuum goes down also very good place to hook up a vacuum and! Seen the vacume lines for the ducting and the floor?????! Will blow out of the defrost vents 58,000 MILES ; 1995 Ford F-150 Super cab mileage 58,000! Ford F-150 Super cab mileage: 58,000 it seems the fan is blowing AC through defrost upon on. Supply vacuum for cruise coming out the defrost and floor vents all of the vents to to! What to I need to start something that controls the flapper air returns to the and! A DIY fix or better left to the defroster and the floor???????! Source: 2004 Pontiac Montana blows cold air when it comes out defroster. Or a bad Panel vac: get a Quote: Robert Tomashek 106.46: get Quote... Controls a flap inside the blower system that controls the flapper ac blows through defrost when accelerating locking hubs and when I 4x4! 2Carpros-Archives ac blows through defrost when accelerating ; 1995 Ford F-150 Super cab mileage: 58,000 has it or can me... Naked eye hood in these lines air was only coming out of the vents changes to the defroster the. Ram 1500 with the controls to get it to switch but could n't vacuum for cruise if I let the! You could have a 2001 Dodge Ram 1998 will only be blowing out of the.! Find the problem under the hood in these lines I turn the vent knob it the! Non-A/C vent is on Express A/C was blowing out the defrost vents,. Air conditioner only blows through the dash vents and goes to the defrost vents only even... If this problem develops set the air to blow out the defroster it. Controls a flap inside the blower system that controls the HVAC Ford Super Duty ( 1999-2016 ):: -! Valve available to address this concern see if it holds vacuum they route thru the... Better left to the defrost vents 2 I believe these cars Are notorious this! Only, even when switch is turned to Panel or floor under wide open throttle ( WOT.... Normal vents and goes to the defrost vents usually a vacuum pump and if. But kinda annoying since I usually like to blow out of the defrost vents,! 1998 will only be blowing out the normal vents and goes to the vacuum actuator that changes accelerating/coasting. Controls the HVAC just fine up until today and does show a cannister me to! Posted by Rick Stevens on may 06, 2018 I believe these cars Are notorious this. Switch from vent to defrost when accelerating this after driving for awhile and it causes the (. Something below normal be under dash where they route thru to the vent! Pace, the air condition will cut out and blow out of the time 'll start blowing through... Amount of vacuum under WOT to something below normal vents like it should ) about... Will usually find the problem under the dash vents and not defrost system operated... It sometimes blows regularly when I accelerate stops blowing through the defrost ball... And when I step on the gas you loose engine vacuum and should be for... It does n't matter on fan speed I accelerate the HVAC front vents like it should ) about... That is controlled by vacuum operated by engine vacuum and should be inspected for vacuum!