[Digger]

Good morning all,

Curious to see if anyone has had the same issue i just went through.

I was driving and all was fine, then all of a sudden it's as if my 2017 Santa Fe Sport Limited went into a "Limp Home Mode" I could not get over 40MPH and my RMP was at 5ooo+, and i had no error codes on dash. I was in luck and already going to the dealer and only a few miles away. When i got there i had the Service Manager get in to see how it was driving and he acknowledged that something was definitely wrong. When we got back to the shop he searched for an error code and system was showing everything was operation properly.

 

[LFLink]

I just got the attached “Product Improvement” notice. Related?

 

[laundrycrisi]

I got a notice from Hyundai today about getting a software update to add a "Knock Sensor Detection System" to monitor for conditions that may precede an engine failure. If the software detects excessive bearing wear, the car will go into a mode like you described as "limp home" mode.

I found articles, but I can't post links yet because my post count is too low.

Apparently the knock sensor is to prevent the engine from spontaneously catching fire during operation. Yikes.

Do a search on Knock Sensor Detection System and you will find the articles I found.

 

[LFLink]

That’s the notice I got. Sorry, it doesn’t look like my attachment attached.

 

[laundrycrisi]

The notice says it's to detect "excessive connecting rod bearing damage". It doesn't mention the risk of engine fire. But that is the reason for the recall, according to the articles I found.

 

[Digger]

Thanks for the responses. My Santa Fe's VIN is not listed on the recall site as having a defect.
I watched the video that Hyundai has about the knock sensor and what the ramifications could be, it sure sounds like it.
I was speaking to my service rep and he thinks its more of a turbo problem. Either way it's still new and if the engine or tranny blows it will get a new one under warranty.

 

[EnonEye]

Got my recall notice in the mail on Monday, had my '18 in yesterday to have the recall work done, took less than an hour. Noticed a pretty loud tick prior to the work upon idle and now it's quiet... yes! I'd get yours in to be checked ASAP.

 

[EnonEye]

Got my recall notice in the mail on Monday, had my '18 in yesterday to have the recall work done, took less than an hour. Noticed a pretty loud tick prior to the work upon idle and it's still as loud as ever. I'd get yours in to be checked ASAP.

Doing 70MPH on way home tonight and engine went into the "limp home" mode as described above. Needless to say with under 9kmiles on the car. We'll see what dealer service has to say tomorrow. NOT HAPPY HYUNDAI

 

[EnonEye]

Update not good. Car needs a new wiring harness and they are produced for each specific VIN so looking at mid to late May to get it back. I got shoehorned into an Elantra as a loaner. Talked with the GM after the service rep and service manager "could do nothing" about a handicapped person trying to get in and out of an Elantra. Car doesn't even have a grab bar as you enter / exit the vehicle. The GM, after speaking privately with the service manager, told me they would let me know as soon as a more appropriate vehicle is turned back in to Hertz for my use. I won't hold my breath and will give them 48 hours before I'm back on them, hopefully I don't injure myself trying to get in/out of this sardine can. Car us under 9k miles, 3rd issue with it now, and I haven't even mentioned a small defective detail about it yet. I don't want them to get too confused at the dealership.

 

[Bruce Gordon]

Limp Mode 1 Week After Knock Sensor Update

We got the knock sensor software update five days ago and last night our Santa Fe went into limp mode (aka Engine Protection Mode). Happened at highway speed about an hour from home. Dropped the car at the dealer this morning. Service consultant says that if this is knock-related issue, their next step (based on previous repairs) is probably a new wiring harness. I've owned and maintained cars for 40 years and it's a real stretch for me to believe a wiring harness is the fix for bearing-related engine knock. Will update as we learn more. 2014 Santa Fe Sport 81,000 miles.

 

[EnonEye]

We got the knock sensor software update five days ago and last night our Santa Fe went into limp mode (aka Engine Protection Mode). Happened at highway speed about an hour from home. Dropped the car at the dealer this morning. Service consultant says that if this is knock-related issue, their next step (based on previous repairs) is probably a new wiring harness. I've owned and maintained cars for 40 years and it's a real stretch for me to believe a wiring harness is the fix for bearing-related engine knock. Will update as we learn more. 2014 Santa Fe Sport 81,000 miles.

Doesn't help you Bruce but thanx for posting, at least now I know there's someone else out there with this same problem. 3 weeks and counting here. Good luck.

 

[RustyMerlot]

Based on what you guys are describing, I am glad to be an older model year. Hope all your issues resolve themselves. Nothing like owning a new-ish car and having unclear repair answers from the dealership when the car leaves you hanging.

 

[Bruce Gordon]

Short update on our 2014 Santa Fe Sport knock sensor/limp home issue: We're screwed.
Long update: Dealer reports they did detect a knock problem and they will install a new wiring harness...when they find one. He reports wiring harnesses are on "national backorder" with no ETA. We have a loaner Sonata for the foreseeable future. BTW, the dealer confirms the wiring harness replacement is done to rule out other (unlikely) sources of engine knock (faulty ignition, bad sensors, electrical gremlins, etc). If the knock code is still there with the new wiring harness, they replace the engine. Hmmm...wonder how long that could take.

 

[EnonEye]

Final update (yea right). Wiring harness replaced, computer tests and test drive passed, I picked up my car today and seems fine on way home. Service tech told me there are 4 steps in this process, some cars are fixed on 1st step and some have to go all the way to step 4 before final resolution. Knock sensor computer adjustment, wiring harness replacement, knock sensor module replacement, and finally a new motor. Oboy! Time will tell. Good having my car back.

 

[Bruce Gordon]

Glad you got your car back! Did they give you any pointers on the next steps? My guess is you'd want to be "stress" testing your motor for highway loads, hills & rpms. That's where bearing knock problems would show up. If the limp home mode triggers again, you know the problem is with the motor and not the electronics. BTW very interesting threads about this problem on the hyundai dash forums dot com website. Look under the active topics tab. I'd post links but I don't have permissions yet.

 

[EnonEye]

agree Bruce on the stressing part, done that about 3 times since I p/u the car with no ill effects, all is well, even solved my loud clicking issue I was having on certain bumps and turns... maybe the test drive tech heard it and torqued a bolt under the chassis??? Maybe I'm senile??? Seems folks discussing this issue on the Hyundai site are of the mindset to not get the update done and rely on warranties in the future. I hate to say it but I trust Hyundai to do the right thing here. I can't see you'd have a leg to stand on claiming a warranty issue down the road when you won't let them fix the problem proactively up front. Time will tell. Computers... love em when they work

 

[Bruce Gordon]

Limp Home Mode Fixed

Wow, we got our wiring harness within a week and our 2014 Santa Fe Sport 2.4 is back on the road. Dealer had a harness ordered for one of their loaner vehicles and gave it to us instead. They also installed a new knock sensor. Their explanation of the wiring repair is that the old wiring harnesses generate electrical interference that triggers the new knock detection software. Anyway, I've got to tip my hat to them for the quick service. With luck we won't see limp home mode...err, Engine Protection Mode ever again.

 

[Seandellison]

In Limp Mode once more

I'm not sure Hyundai really knows what the issue is . I had the ecu update done a month ago, and all was fine. The family and I headed out for vacation on Saturday June 8 and my 2014 Santa Fe Sport went into Limp Mode about 10 minutes into our drive. I managed to drive it to the nearby Hyundai dealership in Marietta, GA. After running numerous tests they replaced the Knock Sensor wiring harness and properly torqued down the knock sensor (car was failing tests after harness replacement because the knock sensor was not torqued to specs). I was told the car was good to go and we were on our way 3 hours after limping into the dealership. About 2 and a half hours later, the car went into limp mode again. I drove another 40 minutes on back roads to the nearest Hyundai dealer in Augusta, GA. Unfortunately, the service department was closed for the day and would not be returning until Monday. We left the car, got a rental, and drove to my in-laws in Virginia Beach. On Wednesday I received a call from the dealer stating they had contacted Hyundai and determined the engine wiring harness needed replacement. We picked the car up on Saturday, the 15th after the work was completed and drove home to Marietta, GA with no issues. After unpacking, I went back out to the grocery, and BAM...Limp Mode AGAIN. I drove it back to the dealer in Marietta. I received a call from the dealer last night. They said the car is testing fine and wanted to know if I would let a tech drive it home with diagnostic equipment hooked up...and I agreed. I received a call this morning stating the tech had no issues. They then asked me about the power inverter that was hard wired to the battery. I informed them it was installed by my buddy's Hyundai dealership in 2014, and I hadn't used it/turned it on since late last year. Their thinking is that the inverter is causing electrical interference that is triggering the knock sensor. They now want to unhook the inverter and test drive my car again, today. I am sure I will receive a call stating all is well and I need to come and pick up my vehicle. Now, when I get behind the wheel, I will be waiting for Limp Mode to kick in again. It is not a matter of if it will happen, but when it will happen. I will keep you all updated on what happens next. As I said earlier, I'm not sure Hyundai really knows what the issue is. Every tech I have talked with has said the same thing in one way or another.

 

[EnonEye]

sucks, thanx for reporting all your troubles, bet I know someone who will never buy Hyundai again

 

[Seandellison]

Small update. I called Crutchfield, the maker of the inverter (Cobra), and two local car stereo installers. All said the inverter is not the issue. One gentleman said he has been installing car stereo systems for over twenty years, and has never heard such a stupid claim.
I can't wait to hear what the dealership has to say tomorrow.