Had my RDX towed in last Friday as my check engine light came on and went in to limp mode. Had it towed 50 miles to the dealer. Was due to have the fuel pump replaced this week. My car is ready and was told that no error codes were stored so they are not sure if it was fuel pump related WTF???? Guess i just made it up then to get a free tow and waste half a day.....

 

IIRC, there have been other reports of "no codes" after this kind of event. Blows the mind.

Obvious questions, was it raining and were you accelerating briskly, when it went into limp mode??
(you may have posted this elsewhere and I missed it, if so I apologize.)

 

search for “limp mode”, you are not the first one. Its
a mysterious problem that has no answers from Acura....
was it really humid/raining hard when it happed?

 

Right on JB, it was raining hard and I just accelerated to get past a bunch of slower cars. Figured maybe low pressure from fuel pump......

 

open a case with Acura and insist your dealer reports to corporate. If more people complain, I am hoping we get some fix from Acura.

 

Just curious, did you shut the engine off and try to restart? Or did you just pull over and call for a tow? I had limp mode with no codes one time under similar circumstances (damp, accelerating past another car), but the car restarted immediately. I just passed 25 months of ownership and only had this happen the one time during the first 6 months of ownership. But I do know to now take it easy on the highway if it’s been raining.

 

Hit the tank hard. Sometimes you'll dislodge the rotor. Start the car and IMMEDIATELY drive home or to you mechanic's shop.

Oh the joys of Chinese circuit boards and ICs. What would we do without them?

 

yes i called for a tow as i found out after it would restart. Did not want to cancel tow as i figured it must be related to the fuel pump issue. Did not know you cant punch it in the rain 🙁 Was not aware its s feature. Stupid me 😂

 

Found these complaints regarding the issue <https://www.carcomplaints.com/Acura/RDX/2019/engine/engine.shtml> . It seems that most if not all the affected rdx’s are 2019. Great, the infotainment issues i can deal with but this problem is downright dangerous and could kill people.

 

If I was a suspicious person, I might think Honda/Acura has instructed the computer to dump the codes when this happens to avoid leaving breadcrumbs. It just seems odd that a fault can occur so significant that the computer has to intervene with limp mode but then doesn't log the reason.

If I was a suspicious person...

 

Bullshit. There's a code stored, heck, the CEL was more than likely on when it went into service since it was towed in. Every vehicle needs to go thru a series of parameters before the ECU/PCM will reset the light on its own. This is likely just a silent recall from Honda/Acura. The Japanese, mainly Toyota, are notorious for it to increase their perceived reliability. Might have done a reflash, might have changed an actual part .... who knows. It's likely fixed though, whatever it was.

https://acurazine.com/forums/3g-rdx-...-p0460-984685/

Brought the car in for the rear tailgate making contact with the roof and forgot to mention the CEL (went off on its own). In the warranty work order though, it mentioned that it was scanned for any updates/TSBs or something of the sort and stated they were all up to date. Agree with the practice or not, at least the issue is getting fixed. If you brought it into an American/Domestic dealership, they would tell you it was completely normal and refuse to fix it until your warranty ran out, then wallop you with a hefty repair bill saying it's something faulty with part X, Y and/or Z. That, or that corporate is refusing the warranty work because reason X, Y and/or Z.

 

when this happened to me a few months ago, my dealer told me Acura is aware of the problem and trying to figure out what it is. Also mine was a 20, not a 19

 

Curious how Acura is trying to figure it out if they have no code for whats causing it?

 

Indeed, such a serious failure that has no code. thats a problem in itself.

 

IIRC, there were some uncorroborated reports of it also happening on some Accords, possibly with the same (similar?) 2.0l Turbo engine.

 

Well I think based on what is happening, they probably have some ideas as to what it can be even without a code. I am thinking they have some pretty smart techs. They did ask a lot of questions.

 

Wow, I played a paranoia straight, but that's a conspiracy royal flush.

 

It’s also interesting that it seems more common in 2019 RDX vs 2020 RDX. Coincidence or they changed something?

 

If they did change something, it was less than a total solution.

Wouldn't any attempt at a rolling fix be a risky admission of a potential safety problem? One that's being ignored in older models? I'm not law savvy, but that seems like a bad thing.

Don't big money injury lawyers excel at uncovering quiet attempts to conceal known dangerous conditions?

 

Indeed, I noticed that pattern after some investigating. When I picked up the car I was also told that all the TSB's were done. Thats total nonsense.

 

2020 Acura here. Got limp mode in heavy rain and nearly got run over by the truck I was trying to pass. Maybe when someone dies they'll fix it.
Took it in. Sorry no code. Not sure what you expect us to fix?!?! (Crown Acura in Richmond)
Also asked them to update my Entertainment system that refuses to update code 057D
sorry, we couldn't get it to update either.

Shrug. Buyers remorse big time.

 

Maybe, Acura is trying to tell us not to try to pass in heavy rain? NAH...that couldn't be it.
It sure is odd they don't have a fix yet.

 

If its the same problem that is in Accord 2.0T, I am sure it will roll into 2021 RDX and also now 2021 TLX. Perhaps more people will complain and prompt action.

 

thank you, after researching for about 2 mins, it seems as the airbox design is pulling water up into the intake and buggering up the MAF sensor.

if any of you are handy, as soon as this happens, pull the filter and see if its wet.

 

I had this thought cross my mind when I began to read about limp mode in heavy rain. If this winds up being the root cause, how in the world did they not uncover this as an issue during development...?? Seems such a basic thing to ensure they get right.

 

the consensus seems to be "if it were an Naturally aspirated engine, it wouldnt happen...the turbo is forcing extra air into the engine...any droplets of water that have been collected in the air box will be forced into the path of the MAF sensor. all due to the design of the intake tract and air box, it's some how collecting water in the air box. "

so to confirm, one of you handy men or women will need to check the air filter after one of these limp mode events....if indeed wet, it could be a real possibility the MAF is getting buggered up.

one could also pull the MAF to look for indications of water...ie; dried up mineral deposits.

 

I've heard of other manufactures adding a screen right before the MAF sensor.
researching ffurther, the screen is called an air straightener and not used to protect MAF, but to straiten incoming air to get consistent air flow to the MAF sensor.

 

seems like the massive thread here on acurazine came to the same conclusion.


I would def. check the air filter to see if it's wet. if indeed wet, one could modify the air box in a way to where it wont collect water.
(I know, it's a brand new car and one shouldnt have to modify something that the manufacture should take care of...but it doesnt look like Acura is going to take care of this)

 

My tinfoil hat sees a lot of use ...


As for water getting into the airbox, I've opened it up after driving thru heavy rain in the past after people speculated about that and found it to be bone dry. Not even a single droplet of moisture. Maybe some are better sealed than others? I have a 2020, and the CEL that popped up for me was when it was dry out. No limp mode, just the CEL. Most curious.

 

it was just a theory anyway, thank you for confirming .

 

All of you that experienced limp mode, please open case with Acura and also ask your dealer to report it. You should also file NHTSA complaint. They need to know its a problem instead of brushing it off

 

While I agree, I just can't imagine that dealers aren't in contact with Acura about this. My humble opinion is Acura is working to determine a cause/resolution. But I also believe it should have been resolved by now.

 

Done

 

It will not have a code of it's own, but it will surely trigger any number of other related codes. There are a ton of fuel related codes. For example, OBDII code P0193 is triggered when fuel pressure is out of range. If a fuel pump stops working, then you should see that code stored in memory. The dealer says no codes were stored, but that's most likely bullshit. Unless there was a strange electrical glitch, there should for sure be at least one code stored in memory.