Sonata NF (2006-10) :: 2009 - Abrupt Downshift At 20 Mph When Cold
Mar 22, 2011
My 09' has developed the abrupt downshift issue at 20 mph when cold. Once the transmission is warmed up, the problem goes away. There is a Service Bulletin on this problem so it is known and a fix is in place. The fix according to the Service Instruction is to remap the transmission software.
How this remap affected their vehicle. My car has been returning great gas mileage, and I am concerned that this fix could hurt that. If mileage is adversely affected, I'd rather live with the downshift IF it won't hurt anything.
View 3 Replies
Advertisement
I just bought a 2009 Hyunda Sonata, 4 cylinder limited edition with 82k miles on it about a month ago. It was maintained to the suggested maintenance schedule by Hyundai dealers prior to me owning it.
after about 2 weeks, it started having issues when slowing down. I narrowed it down to being a harsh downshift from 4th to 3rd when breaking when cold. After driving for 10 minutes it doesn't do it anymore.
My temporary fix is to manually downshift it into 3rd when I have to slow down. It seems to be that it stays in 4th too long and shifts late into 3rd, but I wouldn't think downshifting late would really matter.
View 2 Replies
My 2010, 4 cyl. auto started giving me hard downshifts awhile ago, when cold. Mainly going from 4 to 3, and 3 to 2. I had the tranny fluid changed a few months ago at 56,000 miles, but no difference. So, that left me with the dealer and this is their diagnosis:
Updated ECM and TCM and hard shift still present. Vehicle will require new PCM (TCM?) to resolve problem.
View 4 Replies
My car also had the hard downshift when engine was cold and under 30mph. I seen where Sbr 711 had posted the TSB 10-AT-007-1
I printed this and took to the local dealer & also showed where it was mentioned as a recall.. The advisor looked up on his computer and showed no recalls for the 09 sonata?
I went ahead and scheduled the reprogram update and was told the technician can pull up more info on recalls than the advisor can? Any way they did the reprogram today and $89. later still no recall? How do I prove that in fact this is a recall & get refunded?
View 12 Replies
My Hyundai is giving me a major headache. I bought a 2009 sonata used a few months back. Not long after I got it, I was having issues with it jerking around 20 mph. Sometimes, it would have a few issues with it jerking some when I was taking off. This was only right after the car was started. I took it to a local Aamco. The guy told me that it was a 2-1 downshift pump. He "relearned" the transmission and the problem went away. Now, it is back. At the time, he did some research and thought it may stem from a calibration update they had issued. He didn't have the Hyundai software to try that fix.
View 3 Replies
I have a 2009 2.4/auto with 32000...original owner...just noticed a weird tranny issue develop over this past cold week in NY...when coming to a slow stop the trans will harsh shift as it down shifts from 2 to 1...
View 8 Replies
This is the not about the plagued 2007/2008 ES350 with the tranmission issue. This is more of a generic issue. My car is a 2009 Lexus ES350 Premium line and was bought as a CPO from a Lexus dealership in Feb 2013. Currently mileage is ~98k KM
Issue: From a cold start and driving the car coming to a complete stop, I've noticed that the shifting from higher gear (2 or 3) down to the first gear at around 15-20 km/h is very abrupt. This is a little bit noticeable during the warm summer months and more pronounced during the winter cold months.
Changes: 1) Flushed transmission fluid last summer at Lexus dealership when the car was at ~78k KM, the issue is still present in the summer but a little less obvious.
What I know about the car is that:Cold start of car, the engine's RPM runs higher until car switches from open to closed loop operation (or was it from close to open loop?) When engine runs at higher RPM, car would want to lunge forward a bit. This is normal and expected. Anyway to assist the engine warm-up faster? (Coolant change? Thermostat change?)
Once the car starts to warms-up (i.e. thermostat shows at about 1/4 of the entire gauge range). This is no longer an issue. When car is fully warmed-up the gauge is at about 1/2 marking as a reference point. So when car is starting to warm-up, is the transmission fluid warming up faster than the engine due to the shifting? Or is the fluid warming up due to the warmth from the engine bay?
Desired Final Results: We all know that Lexus are well known for a smooth and comfortable ride. And from a cold start, the shift characteristics isn't smooth. What can be done to solve this issue?
View 4 Replies
Basically when I have it cranked on high (level 4) it feels like its blowing on level 2. some times when I start the car it doesn't even turn on. I have to tap or hit under the glove box for it to start. Is it wiring or could it be AC Blower fan or something else.
View 3 Replies
I have 114,00 miles on my car. Plugs changed and decarbonization done at 99,000 as well as ECM reprogram or update ($99). Anyway, when my car sits overnight and starts it is getting a rough high idle until I feather the pedal or give it a minute or 2 and it is fine. It is warm now in the 70's and this just started. I had it to the dealer for oil change and they looked at it. There are no codes, they recommended changing the plugs and doing a decarb again. So I told them if I need plugs there is something wrong, Iridium OEM were installed.
Anyway, they suggested changing the throttle body since it has new sensors. I have have the TPS replaced before when engine was surging. They told me there are 2 sensors and one could be bad in throttle body. I don't get it, I use Hyundai air filter now and change every 15,000 miles and get oil changes regularly and they use Quaker State Synthetic blend. I am wondering if maybe I have a faulty PCV? I don't think that has been changed. Don't even know what the interval is. Previously I was told there was none, but I disagree.
What would cause me to get carbon build up like they keep telling me? I don't want trial and error and throw parts and money at it since there are no codes. I was going to drive it til it throws a code. I do highway driving in suburban area, mostly 65 mph. The car runs good, still the intermittent hard downshift when slowing down but nothing like before the tranny was replaced.
View 2 Replies
The last couple of times I've started the car from a cold start the RPM's fluctuate up and down for about 30 seconds and then it stops.
View 8 Replies
My 2009 Sonata Limited always has the front window defroster come on in cooler temps when the climate control is set to AUTO. This is aggravating since it shouldn't do that. I took it in for service last year at this time and they didn't find anything wrong and I gave up arguing with the dealer about it.
Is there a sensor or something that is out of adjustment? It comes one when the temp is about 40F or lower and you just start the car after it's been sitting cold. I don't notice it so much when I am out on multiple errands.
Another thing that I notice is that I can never just turn the fans on for air circulation when the temps are moderate, not needing A/C or heat. If it turn the fan on, it always seems to blow cold air feeling like the A/C is on, even if it is not in AUTO mode. I complained about the same thing and the dealer said the unit is operating OK.
View 4 Replies
My 09 Sonata GLS has 50k miles on it. I bought it as a demo model with 9k on it (regret that) as new ... who knows how it was treated.
at 40k miles I noticed that in the morning when I was braking the car would feel like it was slipping out of gear momentarily and it was pretty rough. After a few minutes it would stop and I could continue on my way. The car is an automatic. I noticed it if I let the car decelerate enough that it dropped into first on its own, or if I used the brakes. I figured it must be due to the cold weather or something and was hoping it would clear up. This was only happening after 8 hours of non-use, overnight in the cold.
View 11 Replies
My 2009 Sonata (4 Cyl.) has begun to downshift very rough while coming to a stop from about 20 mph. At first I thought it was the brakes, but now I'm convinced it's the transmission. Essentially it "jerks" a couple of times before stopping. It started happening at 30,000+ and only happens when transmission is still cold. Once I've driven for a bit it doesn't happen.
View 7 Replies
I have 2010 Sonata with 4 cylinder engine and 50,000 miles. For a while now, my car has a real hard downshift at around 20mph. When i put the car in shiftronics mode and do not downshift manually, at the 20mph hard downshift the car is shifting from 4th to 3rd. A while back i had the TSB for hard downshift and also did a tranny fluid flush. Neither has seemed to solve the problem.
Also, the car has a annoying electrical hum/whine that is coming from the engine bay. When i shift car into neutral the hum/whine goes away. Also sometimes when shifting into lower gears the hum/whine will go away for a short period of time.
View 4 Replies
Well, After reading about the weird transmission issues these cars have...mine finally started to do it. It will clunk, shake the car when it shifts and downshift for no apparent reason. All of this does NOT happen all the time. The noises that come from my transmission do though.
I can have the car in Drive and have my foot on the brake and I can hear a grinding/low power steering fluid like sound that comes and goes. Its worse when I shift from Park to Reverse though. It sounds like air being released followed by a bunch of faint grinding noises.
View 7 Replies
I have an 09 Limited with the dual automatic climate control. It finally got cool enough to start running the heater. The passenger side vents are throwing cold air instead of warm like the drivers side. This includes the windshield defroster. I'm thinking there is a diverter "somewhere" that is not working properly.
View 2 Replies
My 2009 Santa-Fe AWD Limited is sick! Starting from a stop, the vehicle has abrupt shifts with the transmission slipping (RPM revving). Seems worse when cold. Checked the fluids, and found ATF fluid in the engine oil and engine oil in the ATF fluid. Quick internet check suggest a leaky vacuum modulator valve. (There is no way the fluids went in the wrong holes, the vehicle only has 69k kilometers on it, so it still has original ATF fluid, and I recently changed the engine oil myself.) So, do you think this is the correct diagnosis? How hard is it to change the modulator, and where is it located?
View 3 Replies
Starting to develop an issue where the trans will exhibit an extremely hard and abrupt shift every now and then - most only during the first couple hundred yards of driving and I think its the 1-2 shift. Only will happen once and only rarely but its becoming more frequent. I have an '11 5.0L supercab auto 4x4, but my father has a similar truck but with the ecoboost which does the same thing on a MUCH more frequent basis. He has been in numerous times with no resolution so I am loathe to expend the energy on "dealing" with them.
View 12 Replies
I have a 06 sonata v6 with 100k and the front end squeaks like crazy. Sounds like possible coil spring problem. It happens more so in the cold. Sort of goes away when really hot n humid. Is it spring related or maybe bushing or upper strut mount??
View 3 Replies
Ok, got a hesitation when the engine is cold, almost feels like a miss. Dealer could not find anything and there are no engine codes. They wanted to replace the plugs with new platinum plugs. I said did you pull any plugs, not that is what the tech said it could be. Could it be the Mass air flow sensor? Or a coil. After a mile or 2 it is fine. I switched to shell premium since dealer told me I had to get a decarbonization from using cheap gas. I used exxon regular and BP regular with a treat of premium every few tanks. But now I am on shell and they said I needed another decarbonization, This is getting rather expensive, I may go back to my local mechanic once the warranty is out. But the hesitation puzzles me.
View 2 Replies
I'm a long time Sonata owner ( 2004 2.7L 291K miles) and recently purchased a 2008 3.3L Sonata with 40K miles and have a question about the 2008 3.3L. I've noticed a ticking sound when the car is cold. The ticking gets quiet between shifts, and eventually goes away once the car is warmed up.
View 5 Replies
