anyone else having rain issues with injen cold air?
 

ever since ive installed my injen cold air intake, its rained twice and its ******* with maf sensors and making car run boggy but easy fix with reseting ecu and and throttle valve relearning. it seems like its getting wet from the top part, entering from the hood area. is anyone else having this problem?

There have been a few members having moisture issues from the Injen intakes that led to poor drivability in rainy or even very humid conditions. I did not, however, hear of any solutions found as most either decided to live with it or get a difference set of intakes.

it's why i drive around with stock boxes. the injens come on on sunny days if i'm at a show or something (i.e. they will never see the light of day ever again.)

sucks balls

Yeesh... that stinks.

I say ditch them for OEM airbox + high flow panel fitlers + smooth intake tubes, or if you really want an aftermarket intake, go with the Stillen G3's.

I have the AEM intakes and they sit around the same area as the injens. I have been pretty hesitant driving it in the rain. I have to get to work though, so I just bought the injen hydroshields. I will install them and report back with results.

I've driven through torrential downpours and the car is outside most of the time and have not had a single issue with my Stillen G3 intakes, very happy with them.

I was going to share this same experience last summer in dry weather when I was experiencing this and then again when it rained but discovered through alot of testing that it only occured under certain circumstances.

1) When the car is parked at at angle, as when the nose of the car is on an upward angle. For instance when washing the car on an inclined driveway.

2) Parking in the rain in a parking stall that places the front nose on an upward angle.

Ever since then I now wash the car in the street on a flat surface. As far as the rain getting into the engine bay and dripping down on the top of the filters was another issue. As I cannot always get a flat surface to park on when it rains.

As it turned out water was entering the hood/engine bay and running down to the tops of the air filters. I even tried to block those areas in the engine bay that have gapping holes fron the inner wheel well. I found that Injen when manufaturing their CAI that they were lucky that Nissan has a 1" in diamter hole cut in the under cover that is exactly positioned to flow air to the inside of the air filters. I plugged the hole with a rubber plug and covered up the gapping hole in the fender well only to discover the air flow and car was gasping for air. All of it was removed and back to square one as to why water only messed with the MAF when the car was parked in the rain or after a wash on my inclined driveway. The car did not get any water on the filter and MAF when its moving only when parked and water is running down the hood.

Turns out Nissan did not do a good job manufacturing the gutters on the inside hood and fender. Then again they did not intend for the stock air box to be removed either. When the car is parked at an upward angle and water from washing the car or rain will seep downthese channels on the fender and make its way to the air filter causing the MAF to either cough very bad or worse put the car into limp mode.

Solution was to take some black weather insulation with adhesive backing (home depot) and run it along the edge of the fender halfway down from the top of the head lamp to bottom of headlamp.

Fixed!

Sorry for the long winded but this bugged the crap out of me when it first occured after my install of the CAI and summer came along and washing the car in the (inclined) driveway. After the fix I got lazy and really thought it was just mine and the bro's Z and no one else was having this problem, maybe because they never wash their car on an inclined driveway or park their car on an inclined parking stall in the rain to have this happen.

Glad I am not the only one having this issue. Btw I still have no regrets buying Injen as I still did not have to cut into my car to get the G3's to fit and accessing the air filters to clean (thru the inner wheel well) is alot easier than removing the bumper. Hope this helps.

For those wanting to pick up some of the filter booties, I ordered some from Amazon and they double shipped me for two cars, so I have extras that I am willing to unload at a good price.

i had this problem in my g37 when i went to the carwash THEN i got the hydroshilelds went back many times has yet too happen again :ughdance:

Good fix :tiphat: I am still debating installing my hydroshields. The $8 weather stripping is another fix.

awesome input with the angles drive way scenario.my first incident was rain on an inclined driveway. the car wouldnt even turn until i rolled it down into the leveled street. thanks for all the post, its keeping me motivated to live with these damn intakes.

@ zforce, i thought the incline was the isolated problem. however the second time it was parked leveled in a parking spot, heavy rain for a day andafter inspection water did enter through the top part of the engine bay around headlights...maybe just amount of rain and time were the factors that caused it to happen again.

Happened once to me! But it has rained 20 times since with no problems. I remember driving through a big puddle when it happened so I really try to watch for that now.
Expecting rain for the rest of this week also!!

It might just be that even on a level surface and prolonged rain that water could seep down the headlight. I fixed mine with the weather stripping during the summer time and over the previous 2010 rainy season I have to guess that there was not enough of constant rain to cause it to choke and go into limp mode. So you may have proved that it even leaks on a level surface with substantial amount of rain pounding on the hood.

I have had mine parked on a flat surface all day during the recent torrential down pour of rain we had here in Sacramento this last week and no problems what so ever. This was after the weather strip fix.

You may want to just get the weather strip, it only takes a couple of minutes to lay it down. I sleep much better now.

Another tip is to be careful when washing the car and spraying water on the inner fender well. I still spray but with low presure and done quickly rather than holding the hose in one spot for any long periods of time.

I would suspect that since you were moving and hit a puddlle that is was the 1" diameter factory cut hole on the under engine plastic belly cover that leads right to the inner side of the air filters is the culprit of where water entered into the area where the air filters reside. You can easliy verify this without even raising the car on jacks, its right below where the filters are situated. I tried to plug this hole with a rubber plug, but it appears that Injen during their R&D discovered this factory cut hole and it benefited with the placement of their air filters. I would say that this is where most if not all of the exterior air enters the sealed compartment of where the air filters reside. It's the main air flow path to the filters.

The Injen Hydroshield booties might help when hitting big puddles with giving the filters a little help with absorbing the water and retaining it before it hits the filters and MAF. I may install the booties on the next oil change.

yeeesh.... all this makes me glad I went with the Stillen Gen II CAI's!

I was not impressed with the G3 install with cutting into the frame. Injen has a cleaner install tube path.

I may just slip on the Injen Hydro shield on my next oil change. I have four extra's (brand new) if anyone is considering these as an extra safe guard.

Part # x-1065red.

PM me if interested.

Injen intake here and no problems with driveability even in torential down pour.

Good to hear, I just washed the cars today and mine choked...oddly the bro's did not...checked for where the water was coming from and found the bottom peice where the front wind deflectors mount, it was not seated in properly from when I had the air filters cleaned.

That's weird. I was afraid of having that on my Stillen Intakes

I had the injens for a good 15,000 miles or so and never had any water issues. Granted I was always extremely careful with puddles.

Buy Stillen G3 then forget your worries. Your not cutting into the frame just a piece of hard plastic, and if you went back to stock it would be covered up were you would never notice.

^ Good to know. Wanna buy some Injens?

Turned out yes, the plastitc shrouding on the inner fender well and lower bumper were not fitted properly on the last air filter cleaning. Fixed now and also installed the hydro shields on one of the Z's. Still out for the results.


At first it sounded and felt like it was restricting air through the CAI. It might just be the placebo effect. I am still testing the difference with shields and with out shields.

Injen Hydro Shields
 

Update: Injen Hyrdo shields installed and the verdict is in: They restrict some air flow.

After installing the hydro shields, the exhaust (Nismo S-Tune), Berk HFC and CAI sounded garbled from 1500 - 3000 rpm. As though the CAI was grasping for air. Thereafter it would pick up from 3000 rpm upwards pulling strong but not coming on (if even that) until 5000 rpm.


Now for the mod: Sliced out (with a razor blade) a .75 x 1.25 piece of the under carriage near the front wheel well, next to the wheel wind deflector. The new hole is cut in the shape of "C"and then folded back.

The results were amazing! Increased air flow over the filters. I regained all of my low end without the garble and it really comes on at 3000 rpm and really punches it at 4000 rpm upward.

One last observation: I proceeded to cut out the bro's Z and his does NOT have the hydro shield installed (yet). The result was a tad less successful then with the shields installed. It did well and was an improvement over normal setup but not the same as with the shields installed. I should have reduced the dimensions of the cut.

A note to those with wanting to test this mod but not wanting to install the hydro shields. I would sugest only cutting half of the the original dimensions. Cut an oval in the size of .35 x .60. Then trim extra as needed to achieve the best volume of air passing through the hole.

If cutting and installing hydro shields then make cut with dimensions at top of this post. The jury is still out as to whether the shields have any benefit. The rain has stopped for the time being. Until the next wash or heavy rain, the results are still out.

If it rains I can always unfold the cut piece and let it hold itself in place or place some duct tape over the flap to keep it in place and water proof.

Butt Dyno = 6
Mod factor = 8 (increases air flow over the air filters and the mod is not visible)

i have the hydroshields and yesterday it was raining hard i did not go in any puddle AND WELL MY G would choke and boggle past 3000 rpm so THE HYDROSHIELDS did not help..
i think i will swap the amsoil dry filters for oiled ones since thats what stillen uses

Not good news, let us know how the oiled air filter works out. Personally I have always switched out the oil for paper. Less HP but better filtration. I actually found mine to be chocking even in dry weather with the hydro shields. Hence my mod. But I see what you are saying and dreaded reading your post.

Did you install the weather strip on the edge of the hood near the headlights? If not, then that would explain why your hydroshields got wet.

^^^ no i did not

Post a pic where the weather shield goes.

I will see about getting a pic posted up.

Thanks ZForce.

Zforce this is news to me, I have had my hydroshields for about 1000 miles and I noticed no difference in how the intakes suck air. I have no loss of power like you explain. Maybe yours were installed incorrectly although I dont know how thats possible, as its pretty simple.

Yeh it took me awhile (like one long days ride) to see and feel the hydro shields robbing air flow. Agree there is no way the shields could be installed incorrectly, it's pretty straight forward. There are two 370Z's in the garage so it makes it simple for a comparision. Both are set up identical except car # 2 does not have the hydro shields installed. Upon test driving both it was very apparent car # 1 w/hydro shield was getting robbed of air flow.

Car # 2 showed some increase in air flow (even though I would have made the cut a smaller hole) being it did not have the hydro shields installed.

Once I did my mod, instant free flowing air across the filters. Good thing about it is I can put it back to stock and test it again anytime. Keep in mind my car also has other mods which may be the difference or no difference you described.

I am running a slighty modded Nismo S-tuned CBE with Berk HFC.

If you are not hearing the engine /CAI making a garbled sound at low rpm from 1500-3000 rpm, then you are probably ok.

If you want to test my mod with the option of setting it back to stock, no harm done, just peace of mind. I really think Injen did not test the air flow and restriction that I found when doing their R&D. I cannot see any other place where the outside air flows thru the front facia to reach the air filters other than from the small 1" hole on the under belly plastic cover that protects the underside of the engine and oil pan. There is some air flowing down the tubes from inside the engine bay as there is an opening in the inner fender well that does provide air. I tested this by covering the opening and sure enough it garbled and lost power.

I will try to get some pics up soon of this mod and the weather stripping mod.

I bought mustang's injens for my Z and haven't had any problems, either. I've had them on the car for about 5000 miles.

Same here, no problems and I love em

Had them on my Nismo for over 6,000 miles and have had no issues even during heavy rain showers.

I just had my injens installed about a week ago and put the hydro shields on from the get go.

I've ran about 600 miles with no issues, no garbled sound, and left her running in one of the most viscous, touchless car washes that I know of, complete with an under carriage wash.

No issues what so ever.

As mentioned before had Injens on my Nismo for over a year. No hydro shields and no problems even in heavy rain storms.