Help needed, 2015 RX350 with Mice!

[Gamalot]

We live in the country and my wife's car is always in the garage each night through the winter. We do get mice in the garage but now we have mice in her car.

On Sunday I found a new born baby mouse on the passenger side front floor mat still alive but too young to move. Again today there is another baby mouse in the same spot. So, we have a mouse nest somewhere in the car, probably in the dash by the glove compartment. I will be tearing into it tonight when she gets home from work.

Please help me here if you can. Where should I look to find how the mice get inside the car from the outside? There has to be some pathway that allows entrance. Has anyone else ever experienced this issue?

How do I rid the car of a mouse infestation? I am well aware that mice can cause very serious damage from their chewing on electrical wires so this needs to be addressed immediately. Her doors and hatch are never left open while in the garage so the mice have a passageway that I must find and close. I just have no idea where to start looking.

 

Thanks

Gary 

[Gamalot]

Update! I tore into the problem last night and located the offender. Picture attached. Behind the glove box there is a cabin air filter and when I removed it I found it completely loaded with mice and a big nest.

I still don't know how the mice get in but this is highly unacceptable. I buy my wife a nice luxury vehicle and she is completely freaked out and wants it gone. She fears driving the car and having a mouse running around on the floor which would wig her right out.

Gary

 

[RickC5]

If you can keep the mice out of your garage, they won't get in the car.  When we first moved into our current house, there were lots of mice around.  Several years of trapping & poisoning them finally eliminated the problem, but I must have caught/killed a couple hundred of them.  Not fun, but I felt my efforts were necessary so we didn't have problems like yours.  Mice love cars, they're warm, and if the mice are hungry they eat the wiring.  You need to eliminate the source.

[mtbmtb01]

Try a cat

we also live in the semi county and have 5

no mice problems but I do have coins and possums coming up to dine on the cat food my wife leaves out.

[glerobi]

On 9/16/2018 at 4:05 PM, mtbmtb01 said:

Try a cat

we also live in the semi county and have 5

no mice problems but I do have coins and possums coming up to dine on the cat food my wife leaves out.

A good vizsla will take care of those raccoons, possums and other critters.  

[Gamalot]

Cats! Yup, tried that until we realized we then need to kill all the coyotes that kill the cats. Trapping and killing the mice is the better plan and I have blocked their entrance into the garage all except for every time we open the new door.

I posted this issue here in the hope of hearing from a Toyota/Lexus technician who knows the vent system and could describe exactly where the mice are able to enter up to the top side of the cabin air filter. If I knew where to look I would make a cover with chicken wire to block their entrance and glue it in if necessary. It just seems ridiculous that a premium vehicle such as a Lexus would leave such an obvious design fault open to mouse intrusion and the stench that follows when they die and permeate the entire cabin with dead mouse stink.

[Les Lex 2018]

If you open the hood, you should see a row of air intake vents (5 0n the 2018) plus drain hole for the water coming off the windshield. I can only tell you that Ive had mice come into the house thru square holes the size of the ones in these vents.  So have no doubt that there is a chance that’s where they are coming in.  To patch the vents with a smaller mesh screen would not be an easy job cutting and pasting all the odd size vent intakes.  Seems like it would be easier to glue down some sticky traps next to the intakes just to see what you catch.

The little critters love peanut butter on their menu.

[Gamalot]

Thanks Les, I am sure you are correct however when I open the hood on my 2015 RX350 the very first thing I see is plastic covers over the entire engine compartment. All of this will need to be popped off and removed before I can even see the vents you speak of. There appears to be an air intake tube that goes forward behind and under the plastic wheel well cowling as well. All of that would have to be popped and removed too. Knowing which of these air intake vents gets the mice directly to the top side of the cabin air filter is the key to tearing into this repair and so far I don't have the benefit of hearing from any technician who honestly knows this system. I could spend a full day dismantling all the shrouds and screening any entry points I can find and still not get it fixed. Back when I first posted this ordeal I also sent an email directly to Lexus customer service hoping they might have some advice. Never got a reply at all from the company.

At the dealer while still under the warranty they offered to replace the cabin air filter for free but I had already done that when I first found the dead mouse babies. They had no clue where or how the mice could have gotten in to that area and really didn't care. They claimed this was the first and only time they ever heard this complaint yet in talking with a mechanic at an auto body repair shop he said he finds mouse nests and dead ones in all sorts of strange places when he is rebuilding cars after crashes, snakes too.

[Les Lex 2018]

The air intake is immediately below the windshield and under the windsheild wipers which set right over the intakes which run all the way across the vehicle. No covers involved.  Designers decided to hide the intake bank behind but not really under the hood.  You don’t see them until you open the hood. Older designs have this bank next to the hood lid and exposed.

[Les Lex 2018]

There is only one air intake and most all vehicles have it in the same place because below the windsheild is the 2nd highest pressure point for collecting positive pressure. Front grill being the first.  The exhaust vents you speak of are at the rear next to the back hatch where the highest negative pressure (vacuum) point is. And the wheel wells are the perfect place to put them. Those vent holes are too small on the inside for mice to get in on my 18. Seems likely that they like to nest in the filter inside of the air intake because that is where they come in.  Restricting these air intakes would likely degrade your climate control system, as defeating the designers intent never turns out great.  IF his design could go with smaller holes, most likely he would have. Mods would be last resort - As it starts getting cold, inspect your filter often - real often... I have had to cut thru dry wall to extract a dead sickening mouse and I know what you went thru.

[Gamalot]

Thank you Les. The very first indication of mouse intrusion was a dead new born mouse dropped from under the glove box onto the floor mat. I did a thorough search of the cabin to find a nest but none was present. A few days later my wife, it is her daily driver, reported the stink which was putrid. I dropped the glove box, found the cabin air filter and the dead mice and nest on the top of the filter. So now I know the mice can make their way through the ducts and up to the intake side.

My thought if it is at all possible is to fasten 1/4 inch square chicken wire fencing over any holes where the adult mice could possibly enter from. As hard as I try I can't possibly keep mice out of the garage. I set traps and catch plenty all winter long but there is an endless supply of mice out here in the country. I expect them in the engine compartment nooks and crannies but have never heard of them entering the cabin air system and even worse, this system is designed to keep the cabin fresh but instead blows the stench of dead mouse throughout the entire cabin. Pretty sad that I as an owner must redesign the system in a premium vehicle such as a Lexus. BTW, Lexus did finally reply and simply said take it to the dealer and have them make the repairs at my expense. At around $100/ hour, No thanks. I would feel a great deal better if Lexus would simply tell me what fix a dealer would do to solve this intrusion. I bet they don't know of a cure but the dealer would be happy to turn his technician lose on my vehicle and take many hundreds of my dollars in the process. 

[Les Lex 2018]

When you park your warm car in a cold place or garage, warm air rises and the vent process is reversed.  Warm air rises thru the intake vent and is replaced by cold air from the rear exhaust vents. Guess where a cold rodent is going to go to get warm and set up their home? They follow the warm, not the cold. Ask your pest control guy what size hole would prevent a mouse from entry. Quarter inch may be too big.  When winter conditions becoming perfect, glue a sticky trap near the windsheild vent and see what you catch.  If you don’t have the money to accommodate Lexus dealers, it can be rough going with few other options.  My one time experience with them was that they were friendly and spent a lot of time explaining to me why I did not have a problem with seat ventalation even though I still think I do, ha ha.

[RB1Shooter]

Gamalot, I live in rural, WY and have exactly the same problem you are having. And like yourself, I am looking for air intake to cabin air system to screen off! Like you, I get idiotic answers like you are getting: traps, sticky boards, etc. Like you, I want to get to the root and fix it there and cannot find any diagrams as to where the air intake(s) are. I am going to local body shop and ask them. Your idea of screening the intake will solve the problem completely, the real queztion is, where is it? If you find out, please let me know. 2015, Lexus RX-350, base owner and very frustrated!

[john stewart III]

i just bought a 2008 RX 400H and went to replace cabin air filter , pulled out air filter and saw  what looks like a pile of lint like insulation? i was able to pull out with tongs and was wondering if mice or packrats can get to this area from under the hood? i live in Tucson  arizona but have never had an issue with this and this car came from the L.A. area of California.Has anybody encountered this issue?  Thnx, John

 

 

 

[john stewart III]

gamelot and Les, I just saw your posts  containing fotos of mouse nests and that is exactly what i found while replacing cabin air filter, so i will see if i can come up with any info regarding sealing off the air intake under the hood without disrupting any hvac systems . I suspect this is an old nest as  there is no stink or any traces of mice !Removed! etc. but will keep my eyes out for any new signs of the little  bstrds!!

[ppine]

I had a pack rat living in the engine compartment of my truck.  They can do real damage as in thousands of dollars worth.  I got serious about controlling rodents.  Mice are only a nuisance in comparison. 

Leave your hood up, leave the light on, add some fragant conifer boughs to our engine compartment. 

Rodents gain access by climbing up the tie rod ends.  Mice might climb up the tires.  Place some spring traps near the front wheels.  The battery operated zapper worked on the pack rat. 

Rodents are serious business. Be proactive and take care of the problem. 

[Farr]

I have a 2013 Lexus RX 350.  Today I found a baby mouse on the floor of the passenger side!  I had no idea how in the world he got there?  You guys comments were so helpful.  After I opened the vent compartment, which is all the way in the back of the glovebox, I found a nest with three more live baby mice.  It was a challenge to take them out.  I used the narrow tip of the vacuum cleaner to pull them out one by one.  The filter was damaged that I ordered on eBay.  Thank you so much.

[Kathy Anderson]

On 9/25/2019 at 9:48 PM, john stewart III said:

i just bought a 2008 RX 400H and went to replace cabin air filter , pulled out air filter and saw  what looks like a pile of lint like insulation? i was able to pull out with tongs and was wondering if mice or packrats can get to this area from under the hood? i live in Tucson  arizona but have never had an issue with this and this car came from the L.A. area of California.Has anybody encountered this issue?  Thnx, John

 

 

 

John, Yes I have a 2008 Lexus RX 350. and have been fighting rats in my car for months now.  They ate through the wires and that cost me $130.00 to replace wires.  We have tried peppermint Oil, electronic waves, rat poison, rat traps and every morning we find new !Removed! under the engine cover, which pops open very easily..The !Removed! is getting smaller so they must have had babies now and refuse to leave my engine to find the traps.  We even put a sticky trap on the engine. The urine smell is horrid. We pressure washed the engine and still they haven't left, because we cannot find them!  Our mechanic fixed the wires but obviously didn't dig any deeper so our only desparate idea is to take it back to him and start taking things apart.

[Jack1944]

Have had this exact problem for many years with my 2005 RX330.  Mice and even rats can get into the cabin air system.  They even bring date pits (from our trees) for their food stores.  I have followed all the comments here for years and no one has ever posted exactly how they can possibly enter the cabin.  In 60 years of owning many models of cars, I have never had this problem with other models.  So discouraging to hear that newer RX models STILL have the same problem.  They are not coming through the 1/8 inch holes in the air intake, or open windows, etc.  My guess is that there must be a hole in the firewall or steering wheel shaft or somewhere so they get in the cabin.  After that, they could crawl into the floor heater vents (no grill mesh on those) under the front seats and end up on top of the cabin air filter.  I have trapped 3 so far this time.  Problem has been ongoing since before gluetraps were invented, and once again, ONLY IN OUR RX330.  No more Lexus for us.  Shameful.

[Les Lex 2018]

Thanks, Jack!  The vent holes on my 2020 are 1/4 inch wide, not 1/8th and even bigger for length.  I keep seeing on internet searches that small rats can fit thru a 1/4 inch hole but mice can't.

I don't know what a small rat is as far as what species... Based on that, you are right. Mice should not be able to get thru the vent to the dirty side of the filter.

Les Lex 2018 / 2020

[Jack1944]

The air grill holes in my RX330 are square, 11/64 inch.  Still trying to figure out how to block mice from accessing the cabin.  Last night I used a field cam on the garage floor to learn that they come and go quite easily, by jumping up on the wheel rim, then up onto the suspension A-frame, then into the engine compartment (see video).  Next step is to try to trace the agile little monsters and find where they enter the cabin.  Also learned that leaving garage lights on at night, moth balls, PVC glue odor, and security lights do not affect them.  They outsmart most traps except glue plates.  But trapping and removing them (8 so far) is not the solution as long as they have such an easy way of re-entering. 

[Les Lex 2018]

Sounds like you live close to Mother Nature, where there is an overpopulation of rodents.  I hate cats but my kid found one.  We made it a nice cozy box in the garage and it was happy running around the area catching mice. I don't recall that we had any rodent problems after that. Didn't need to buy cat food after that.

Nothing like the balance of nature. But getting back to your problem, the exit vents are way in the back of most all vehicles.

Once again, the vent opening is 1/4 in on the 2020 RX here.

[Jack1944]

Yes, we have lots of rodents outside, and also have been storing 500 lbs of goose food in the garage, which has become a big self-serve mouse buffet .  We are moving all feed storage elsewhere, but have had mice and rats in the RX330 since long before the feed storage.  I'm sorry I wasn't more clear about the "air vents" I was referring to - see photos.  The 11/64 square holes are in the air intake grills under the hood in the engine compartment, which some people had mentioned as a  possible entry point.  I can't see how that could be the problem.  Other people have mentioned the holes where the hood hinges are located - they suggest taping these holes (see red tape in photo), but those holes have drains that route rainwater behind the wheel well and no grills at all, something I can't imagine Lexus would use as an air intake route.  The in-cabin vents I was referring to in my 2005 RX330 are the under-the-front-seats ducts that blow A/C or heater air onto the feet of rear passengers (see photo).  They are nearly 1/2 inch tall x 8 inches wide, with no grills.  I am surmising that mice somehow find their way into the cabin, and then find their way into the heating system through these floor ducts.  They end up on top of the cabin air filter, where they make nests and quite a mess.  That access route is all a guess on my part, but I will keep using my trail cam to try to figure this out.  (Also see photo of a sheet metal car corral solution that worked for someone in a rural environment.)

[Les Lex 2018]

There is only one location for air "intended' to enter the vehicle and that is below the windshield as you show.

Air exits the vehicle via the vent I showed you in the rear. After air enters the dirty side of the filter, it then goes to the condenser coil and then out all the vents provided.

1. IF they are nesting on the dirty side of the filter, they are coming in thru the windshield intake or some other opening that is not intended to be there in that path. All air from the windshield intake is suppose to go to the cabin air filter. Lexus does not want dust in your condenser or your cabin.

2. If they are nesting on the clean side of the filter, they are coming in from some where else and going thru the air vents and they can get into your condenser coils and on to the clean side of the air filter.  But, see below:

I think you hit on something - The drain hole! That hole is inside the cage where air is collected and sent to the air filter. If they come in there, they get a free ticket to the air filter.

 

[Gamalot]

I don't think mice can get to the top "Dirty side intake" of the cabin air filter from the under the seat air flow outputs. I also don't believe they can shimmy through the air intake vents on the fire wall. What I do know for sure is they can and do get onto the top "Dirty side" of the cabin air filter. Just a rather uneducated guess here but our heat/AC systems do have a setting for recirculating inside cabin air and then blowing it out through the vents. This is likely some sort of flap between the outside air and the interior air that opens and closes. I have no idea where the intake suction side of the recirculation vent might be but this is where I suspect mice can get to the top side of the cabin air filter. I am very sure mice can get inside the interior of my RX350 with no trouble whatsoever. They ate my candy in the cup holder. Once inside the cabin they apparently search for a way back out and some end up on the top side of my cabin air filter. I showed pictures of dead newborn mice laying on top of the filter and the car had a stink like dead mice until I finally located them and that happened when my wife had a dead baby drop onto her foot from behind the glove box.

After all this time that this discussion has been going on we would think some "rocket scientist/design engineer" employed at Toyota/Lexus might have chimed in and shown us the possible route the critters could be taking. My bet is Lexus has the ability to show the entire air flow system in a simple computer generated schematic with all the other systems removed and arrows showing the flow direction. Basically just a wiring diagram but for only the air flow vent duct system.

I do love seeing the trail cam pictures of the mice on the move. Too bad we can't see any points or racks on the critters. I have caught a lot of mice in my garage but never did check if they were bucks or does.