Why Does 91 Ls 400 Passes Hot Air Inside While The Car Is On The Run &

[sheab]

I have 91 LS 400 and its got about 144 miles . runs okay but i notice when i drive the car hot air comes through the vents.. while the the heat botton is turn off for sure. it only happen when i drive and when the car is parked and engine run its okay the hot air doesnt come by vent . what should i do plz . what could be the reason for it? and how can i resolve the problem? and abt how much do i have to spend? what neded to be change for it to work back to normal ? any comments and help will really help !!!!!!!!!deshicyberchat.com

[92Lex]

Air comes in behind the button? Or is it through the vents? Are you sure the button is set to the off/re-circulating air when it is off? Orange would be off.

[sheab]

Air comes in behind the button? Or is it through the vents? Are you sure the button is set to the off/re-circulating air when it is off? Orange would be off.

its come by the vent yes the button if opp i enven press the off button couple of time but the hot air comes only when i drive .. siting the car runing the engine without driving .. its okay .. but driving it makes the hot air come through the vent .. any one help plz !

[92Lex]

There's an actuator that controls vented air vs. cabin/re-circulating air. That motor/arm is most likely broken...thus causing air to be drawn in (vented) regardless of the position of the button. I guess what I'm trying to say is....the vented air position is stuck in the "open" position and the button has no control over it.

[sheab]

There's an actuator that controls vented air vs. cabin/re-circulating air. That motor/arm is most likely broken...thus causing air to be drawn in (vented) regardless of the position of the button. I guess what I'm trying to say is....the vented air position is stuck in the "open" position and the button has no control over it.

sorry didnt get it can u make it more clear where is the mortor arm located

[92Lex]

Not sure if you'll want to remove the A/C suitcase...it's a hell of a job. It's behind the dash. Right next to the heater core. I'm not sure which year LS you own but 90-94's call for about 4 hours of labor if I recall. Are you going to be taking on this task yourself?

[sheab]

Not sure if you'll want to remove the A/C suitcase...it's a hell of a job. It's behind the dash. I'm not sure which year LS you own but 90-94's call for about 4 hours of labor. Are you going to be taking on this task yourself?

are u sure that is the problem // cuz when i turn on the a/c or heater button its work fine .. i mean its turn on and off ... what i mean is the problem is that .. when i drive then engine hit get inside by the vent how do i fix that ? and why the engine hit geats inside when i drive the car . the air doesnt get in when i doont drive the car .. even though the engine is running // does it helps or make it more clear of the problem thanks for ur time buddy !

[92Lex]

No, you're confusing me as hell. Haha. According to how I first read this post, you're having problems with hot air being vented in while your vehicle is in motion...yeah? Even though all the buttons are off. Including the vent/outside air option being switched off. If that's the case then I would suspect that to be the problem. No guaranty though, unless you decided to pay me =).

Man, it's 4:44 am your time...and I thought I was the only one with problems sleeping. Any suggestions for a good sleep med? I thought country music would help but I'm still wide awake!! Haha.

[Paul Sherman]

Ok, maybe I'm missing something here, but I didn't see

this question directly answered.

sheab, my first question is - when you have the heat shut off,

is the vent set for fresh or recycled air?

With my '93, I always get air coming in while in motion when the

system's shut off if I leave the system set to allow fresh air.

The air intake is (at least on mine), independent of whether

the system is on or off.

(I was grateful for this when my fan died in summer - I had

SOME A/C while driving)

So, do you still get air through the vents with the system

shut off AND the air set to recirc? If so, then the others have

excellent solutions.

[sheab]

Ok, maybe I'm missing something here, but I didn't see

this question directly answered.

sheab, my first question is - when you have the heat shut off,

is the vent set for fresh or recycled air?

With my '93, I always get air coming in while in motion when the

system's shut off if I leave the system set to allow fresh air.

The air intake is (at least on mine), independent of whether

the system is on or off.

(I was grateful for this when my fan died in summer - I had

SOME A/C while driving)

So, do you still get air through the vents with the system

shut off AND the air set to recirc? If so, then the others have

excellent solutions.

yes the hot air get through the vents eventhough the button is turn off so what is the excellent solutions

while i read ur post i found that ur problem is smilier to mine like it only happen when the car is in motion .umm when its park and the engine run i dont notice it but when it runs thats is air start to comes in by the vent .. so tell me what next!!! and what u mean by "is the vent set for fresh or recycled air after the heat buton turn off?" how do i know if the vent is set fresh air after the buton is off i just tryed set off button thats all .. give me a full detail if possible plz thanks !!

[92Lex]

Do you get air coming through at cruising speeds regardless of the position of the button? If yes, somethings messed up. Your climate control system isn't working properly.

You're confusing me. Based on what I understand, you only get un-wanted air at cruise speeds...not at idle. So I would say that the actuator is defective.

[sheab]

i do get hot air coming through the vent while the car is in motion and while the position of the button is set off for ac and heat. so what could be messed up??

[swordfish]

hi there

I had this problem and fixed it as follows:

THere should be a big rubber seal goes across rear of engine bay to seal against underside rear of engine hood and top of engine compartment when hood is closed.

Mine was not there. Probably lost after a accident repair, or became hard and someone took it off.

It is like 4 foot long and 3-4 inches wide.

If it is not there or is seroiusly deteriorated, hot air from the engine bay is sucked into your fresh air intakes

which are under your windscreen wipers, as car goes along. Usually if you go faster highway speeds, enough cool air is sucked in you dont notice the heat so much. Also you can get oil fume smells as well.

Jus t get a new seal, about $100 I paid in Australia as a genuine part, ex Japan. Put it on yourself in 5 minutes,

happy days!

swordfish

if u are lost I can take pictures of it and post for you, let me know.

[sheab]

hi there

I had this problem and fixed it as follows:

THere should be a big rubber seal goes across rear of engine bay to seal against underside rear of engine hood and top of engine compartment when hood is closed.

Mine was not there. Probably lost after a accident repair, or became hard and someone took it off.

It is like 4 foot long and 3-4 inches wide.

If it is not there or is seroiusly deteriorated, hot air from the engine bay is sucked into your fresh air intakes

which are under your windscreen wipers, as car goes along. Usually if you go faster highway speeds, enough cool air is sucked in you dont notice the heat so much. Also you can get oil fume smells as well.

Jus t get a new seal, about $100 I paid in Australia as a genuine part, ex Japan. Put it on yourself in 5 minutes,

happy days!

swordfish

if u are lost I can take pictures of it and post for you, let me know.

thanks .. ur the best .. well im kinda lost but yes thats what is the problem when i took it to the dealer but its a heak alot of monay they ask for can u take some picture and display thats will be really help full thanks alot ... the isuee has been found now need to install it so plz post the pic thanks !

[swordfish]

will do, but it will be tomorrow now, its dark and raining here at the moment.

the seal just clips on to the raised edge along the rear of the engine bay, no tools required, i did it in about

10 minutes, just make sure it goes up the right way, dont press it down on the clips till yu are sure you

have it about the right way.

swordfish

[ko90ls]

so this seal is under the lower engine shield? mine does the same thing but i thought it was natural... like if i set the cabin temp to 60 it will blow cold air and vice versa. but i always use the outside air unless using the A/C.

[sheab]

so this seal is under the lower engine shield? mine does the same thing but i thought it was natural... like if i set the cabin temp to 60 it will blow cold air and vice versa. but i always use the outside air unless using the A/C.

simple just turn off the recyle button off .. thats all u wont get anyait i think ur main problem is ur fresh air (recyle button) is on let me no if that help