vegitto02

New member here, and sorry for yet another post on this topic. However, I wanted to check in with folks here whether they got their car serviced under the TSB and whether finally it resolved the limp mode. The TSB I'm referring to is linked here:
https://acurazine.com/forums/third-g...letins-988390/

Namely, has anyone still experienced limp mode after servicing done for the TSB? I am a prospective 2021 RDX SH-AWD Tech buyer and am hesitating on this purchase given this issue (and perhaps some other ones, e.g. brake squealing).

Many thanks.

DrWoo

Hard to answer this with any certainty. I had the TSB done almost 2 months ago, but it’s been over 2 years since I experienced limp mode on my 2019. I will say that the car seems to accelerate smoother since the TSB - I used to experience a slight hesitation when stepping on the gas from a stop, and that is gone now.

Predaconcept

Exactly what I'm looking to learn more about. Didn't see a lot on reddit about the limp mode resolve.

Mike Earwood

I asked the Acura dealer to do the 20-053 TSB when I went in to have the fuel pump recall done. When I picked up my ASPEC they said they didn't do the TSB because THEY didn't think it was related to my limp home problem. They also said they didn't want to do it because my car was out of warranty!!! WTF!!! I love my ASPEC but I think it's time to buy a Tesla...

vegitto02

Thank you for the response and glad you are experiencing a smoother ride. Hopefully the issue does not come back!

vegitto02

Glad the car is feeling smoother and hope you don't experience the issue again!

vegitto02

This is unfortunate that they did not service it. How is your 3rd gen out of warranty? I thought these were covered for four years. They don't think the TSB fixes limp mode? In which case, it's an open issue without resolution still?

eVojlib

2021 Models have both the updated fuel pump module* and the intercooler update kit installed which on 19*/20 models can create a stall and or limp mode.

4th Acura

My 2020 RDX had the intercooler replacement repair about a month ago. So far all is well. I have not had a chance to floor the accelerator in heavy rain.

russianDude

Can you please share your experience with the dealer to get this work done. Did they give you hard time questioning you ?

4th Acura

Surprisingly, my dealer was cooperative. I described the circumstances of the limp mode incident and the service guy asked me about which dash warning lights were on. I told him a flashing yellow engine warning light and they booked the appointment. They also repaired the moaning rear hatch.

EFR

There is nothing on the RDX that makes me more worried/concerned/scared than this limp mode thing. I could not imagine flying along at 65/70 on the freeway and have this kick in. This could be the cause of serious injury, or worse from what I read. The fact that we only have 11,000+ miles after 3 yrs, 3 months, and living in a place where it pretty much never rains is the difference between it having it happened or not. And there is no other way to know if your RDX is susceptible.

russianDude

you had to bring it in, or arranged appointment over the phone?
thanks

russianDude

yeah, it never happened with me either in 2 years, but a thought of it happening even once in a bad place makes me nervous.

4th Acura

I had my car in for winter tire installation when I told them about my limp mode episode.

Ron T

"Namely, has anyone still experienced limp mode after servicing done for the TSB?"

Yes. Just had it happen yesterday. The TSB was done in March of 2021 on my 2020 RDX Advance.

We were on I-10 in the Florida panhandle and it had been raining for some time. A vehicle in the right lane ahead of me was going too slow so when I saw an opening in the left lane where I could safely change lanes, I pressed the gas pedal quite a bit so I could quickly get up to a matching speed for the left-lane vehicles. That is when the fun began! The engine stumbled a couple of times and the check engine light started flashing. No matter how much I pressed on the gas pedal, the car would not accelerate. I managed to get back over to the right and into the breakdown lane. Fortunately, based on other's experiences documented in here, I knew immediately what had happened and explained this to my wife as I was getting the vehicle stopped. I got a picture of the instruments showing the check engine light and the odometer. I turned the vehicle off, restarted the engine and all was well once again. Made it the rest of the way home without issue.

I will call the dealer today and set up an appointment to diagnose, but I doubt there will be anything stored.

Ron

EFR

How is this not a mandatory recall? At what point is a death or serious injury going to occur when an 18 wheeler bears down on your 'limping' car....if it has not happened already. Granted we are not reading this a lot, but this is one little blog used by a fraction of the owners....and then limited to someone who is in the right rainy conditions. Our 2019 (maybe) has not done it because we have only 20K miles on it in 4 1/2 years....have not really driven in any kind of rain...and maybe it's one that does it, maybe not.

RDX 3G A-SPEC

I had this TSB performed yesterday and it did nothing to resolve the limp mode issues. It stalls under hard acceleration and check engine light comes on. Took my 2019 RDX A-Spec back to the dealer and they said they would be calling California to to determine what to do next. The issues started driving in rain. 4 year/50K mile warranty runs out next month.

EFR

That's an interesting dilemma regarding the warranty running out soon. I am not sure how the warranty is treated in a situation like that where you have a current and or ongoing issue, and a warranty ending. Our 2019 is the only new car I have ever bought an extended warranty for, and we got a 4 yr/50K mile one directly from Acura....and as best I understand it mimics the original warranty and all it's benefits and features for 4 more years. Our 2019 hits 4 yrs this September so obviously we have not used it yet. It would seem if you are having an active problem and it is still under warranty, they have to fix that. I believe someone posted here that you can still purchase an extended warranty from Acura before the current new car warranty runs out. The amount of things, expensive things, that can wrong on a new car could be extensive. Whether is is worth paying for an extension depends on a lot of things, and plenty of people have varying opinions. It still surprises me that with the safety hazard presented by the limp mode issue that Acura has not been forced to fix it.

Ron T

I meant to report back after my service visit on my previous post.

This is from the invoice I received:

• No codes were stored. (As expected)
• Road tested the car and could not duplicate.
• Checked all intercooler connections. All OK.
• Checked coilpacks for water intrusion. None found.
• Checked OTA system for update but system is up to date.
• Contacted Techline. Was advised to:
  • Check all intercooler connections.
  • Check for updates with HDS.
• Checked for updates with J2534. Found PGM-FI update available and performed update.
• Performed idle learn procedure.
• Performed throttle learn procedure.

So, the end result is that the vehicle got one software update, but I don't know if that update contains anything that addresses the issue.

I submitted a complaint on the NHTSA site to make sure it is documented.
A quick review of that site for the 2019 through 2022 RDX with reports of this issue found:

2019 69 with this issue of 192 total complaints
2020 54 with this issue of 132 total complaints
2021 11 with this issue of 35 total complaints
2022 1 with this issue of 8 total complaints

How this isn't a recall or at least an open investigation by the NHTSA escapes me.

Ron

EFR

I'm with you my friend. While our '19 has not done this limp thing (yet), those that have described what occurs, it would scare the living hell out of me...freeway...raining/slick road....pretty high speed...traffic...and then it all shuts down. Our plan is to give this '19 to our daughter as soon as we can secure a new SUV. All I can do is make sure she is aware of it...and think fast if it ever happened.

4th Acura

I haven’t had another limp mode episode since my intercooler was replaced a year and a half ago. There were other things done to the car during the repair but I am unsure what they were, I think there may have been a software update. I have a 2020 Canadian RDX. So far, under warranty, I’ve had the intercooler replaced, the moaning rear hatch fixed, the exploding rear window replaced and numerous software updates. For a past year I’ve been waiting for a warranty replacement to my molten HUD display.

4th Acura

In case your interested, my wife’s 2016 MDX has never had a problem.

mvl

Have any of you received 23-010? Not sure what it does but the need for an oil change makes me guess a turbo overheat?

Plan to get it on my next oil change for my 22 but curious if anyone has still experienced limp mode after it?

RDX 3G A-SPEC

California office advised them to check the spark plugs and they were fouled by the water intake in the intercooler. They replaced the spark plugs free of charges and the issue is resolved.

EFR

I am not familiar with an intercooler.....guessing it is part of the turbo setup? If they were "fouled by the water intake in the intercooler."....then it's normal that water gets in the intercooler, presumably from rain?

NBPDC505

Once the hot air comes out of the turbo closer to the passenger side it is routed through the intercooler located in the front grill of the vehicle to cool the air down before it goes up the drivers side fender under the battery and into the engine. There should not be anything from the outside, including water, making its way into the intake tract from the intercooler itself or the joints for hoses into and out of it. The amount of air is metered by the MAF at the airbox and a leak/opening of any kind is unacceptable since the ECU has already accounted for a specific amount.

EFR

Got it. So the intercooler was replaced as part of the TSB, leaving fouled plugs behind. Those were then replaced and problem solved....Presumably.

Ron T

Were the plugs replaced as a follow up to 20-053 (intercooler replacement) or to 23-010? Either way, I will talk to our service advisor on our next visit and ask them to check the state of the plugs.

Ron

RDX 3G A-SPEC

plugs replaced as follow up after 20-053 did not fix issue. I would definitely have plugs checked after 20-053.

Geohutch

My 2019 RDX felt as though it shifted int neutral while accelerating at my 60 mph. I noticed the RPM’s were over 5,000. Gear indicator still showed a D but I could rev the engine. Slowed down and it finally engaged. Pulled over, restarted, drove off and same thing happened again within a few miles. No codes were stored. Dealer can’t find any problems or reproduce the issue. I did not notice the engine light coming on but I was freaked so maybe I just didn’t notice.

is this different than the limp mode? Has anyone else experienced this?

I also experienced unexpected hard acceleration for about 2 seconds at maybe 5 mph with foot jamming the brake to stop the acceleration. Anyone ever hear of this. No codes were stored again of course.

4th Acura

Doesn’t sound like limp mode to me. Limp mode is characterized by 2000 rpm and 30 mph max while flooring it. Limp mode resolves by restarting the car and conservatively using the throttle. My experience was during full throttle during a heavy downpour while merging on a highway.

Ron T

[This first part isn't related to limp mode, but you'll see why I am posting this here shortly.]

We just completed our first road trip in our 2024 RDX Advance SH-AWD. Round trip from Treasure Coast Florida to New Orleans of 1700 miles.
We averaged 25 MPG overall with a high of 26 on one fill-up (calculated), slightly better than our 2020 RDX on the same trip.

The '24 was quieter than the '20 and the ride a bit more comfortable using Comfort mode most of the trip.

[Now the reason I posted this here.]

Unfortunately, we learned first-hand that Acura has not resolved the Limp Mode issue under heavy acceleration in wet conditions.

We usually split the drive over two days and the incident occurred on day two. Conditions were light fog and roads were dry, although the previous day we drove about six hours, two or three times in very heavy rain. The rain continued right up until we stopped for the night.

We were driving eastbound in Florida (two eastbound lanes) in the right lane. We were approaching a Semi-trailer followed by a medium-sized box truck and switched to the left lane to pass both vehicles. Another vehicle was approaching from behind in the left lane and I "floored" the accelerator pedal to quickly pass the two trucks. The RDX downshifted as expected and the engine revs increased briefly, but suddenly the Check Engine light started flashing and the car lost power and went into Limp Mode. Pressing the accelerator to the floor made little difference. Instead of quickly passing I was only able to get past the two trucks at a slow rate with a line of vehicles growing behind me. I think we were on an incline and the trucks were slowly losing speed. Eventually I was able to get past the trucks, switch lanes and quickly move over to the breakdown lane. If there had been heavier traffic, this could have easily resulted in a serious accident. I restarted the vehicle and resumed our trip without further incident. The vehicle odometer was at 4040 miles at the time of the incident.

A visit to the dealer resulted in:
1. Unable to duplicate.
2. No stored codes and no pending codes.
3. Software all up to date.
4. Removed coil packs and spark plugs to check for water intrusion or cracked plugs.
All spark plugs were clean without cracks or signs of water intrusion.
5. Road tested again and could not duplicate.

The dealer commented that the issue was now in the system so if it should happen again, they will have record of it. Well, that makes me feel better! That assumes the next time doesn't result in a serious accident because the car decides to go into Limp Mode in the middle of heavy traffic at the most inopportune time.

I filed a complaint on the NHTSA site and noted that there are hundreds of reports for this issue on 2019 through 2024 RDX (3rd gen).

I emailed Acura Client Relations to see what they have to say and what to do next. A representative called and we discussed the issue for some time, but in the end, she said the same thing the dealer did: The incident was in the system, so if it happened again. etc. I said, that assumes the next time it happens I'm not dead from the accident that occurred. I also asked how it was possible that the vehicle detected an issue that triggered the Check Engine light and put the vehicle in Limp Mode and yet no codes were stored? Of course, she had no explanation for that.

We love the vehicle. However, I cannot feel comfortable driving a vehicle if I cannot trust that it will accelerate when called upon to do so. There should be no hesitation on my part to fully press the gas pedal under any conditions. In fact, that is how it happened. I instinctively “floored it” in order to pass vehicles and that’s when we found ourselves in a frightening situation. Now, I have to “think” before I do so in fear of another incident. This should not be so.

Ron