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indy-tech, Import tech
Category: Hyundai
Satisfied Customers: 8051
Experience:  Work on all import vehicles
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We have 2006 coupe auto.had a problem where the gearbox

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We have 2006 coupe auto.had a problem where the gearbox appeared to jump and made a big bang,,,advised to change the gearbox which we did ( it was a used gearbox off a 2006 model done 55,000miles ,can it be the gearbox again or something else

Hi, I'm Greg (Indy-Tech).
Welcome to JustAnswer. I'm reviewing your question now, and will post back with your reply ASAP.
Rgds Greg.

One question so we are on the same page .

What diagnostic checks did you do to confirm a bad transmission .

Was no diagnostic scan tool hooked up to check for transmission malfunction codes .


Customer: replied 2 years ago.
Hi Greg,,,
I took the Car to a renowned mechanic for auto gearboxes,,,,what diagnostics he used i have no idea,as I left the Car with him to investigate..There was one reading that he said was low,but that may have .been to the fact that the flexi exhaust had fractured due to the jolt when the gearbox malfunctioned,he then apparently took the Car for a road test,and on the strength of that diagnosed the gearbox was faulty.
As we are Pensioners a new gearbox at over 3k and recon at over 2k our only option was to get a used gearbox with a short warranty, Anyway the gearbox was replaced with the used one,and a new flexi exhaust was fitted.I took the Car for a test drive seemed fine,,however after only about 2 miles the same problem occurred,,,,gearbox jolt and bang at about 20mph
I rang the engineer who was amazed at this ,,,and said he would ask another Expert!!!! His opinion,,This engineer then suggested it may be the some thing clutch!!!??? problem,,,This was Saturday havnt had any reply as yet.
I have contacted our local Hyundai Dealer, and I am taking the Car on Wednesday for them to check with their equipment?.but if you can advise then it will save me £80.
Many thanks Greg,I await your reply

Hi Bernard .

I fear that you may have changed a good gearbox for nothing .

As for this issue is a update TCM reprogram to sort out this problem .

IF was already done and still issue then could an issue with the transmission input and output controls .

You will have to have the car hooked up and checked for engine and transmission management

codes .

From the malfunction codes you will then know what has been causing you this issue .

Very common for this would be a TSB for the update reflash/reprogram .

Your dealer will have information on this issue and will advise what is best done .

Sad the Transmission shop did not check for TSB for this concern first...

Need further assistance with this issue then please get back to me with the reply box below .
After rating there is no further cost for any other question relating this issue .
Kind regards Greg

Customer: replied 2 years ago.
Many thanks for your prompt reply Greg.I have relayed this information to the Mechanic,he said there were no codes he could find to check this,,,,either his diagnostics isn't up to date or he isn't up to speed with it.
We are taking the Car back to him and he is going to flush and back flush some pipe!!!!!
I will let you know the outcome Greg.
Thanks again for your assistance in this matter.

Hi Bernard .

Okay if no codes have him check with the dealer for any TSB concerning this issue they maybe a reflash to

rectify this issue .

Rgds Greg

indy-tech and other Hyundai Specialists are ready to help you
Customer: replied 2 years ago.
Greg Hi
No luck with the g/box problem,as you know the same thing "Smash Selection"!!! is occurring with the swapped used g/box.
I visited a free chat line,and was advised it cannot be the g/box again to coincidental,he suggested that the problem was either sensors ,pressure,adaptions,,Scania? ???? or something else.Anyway I am in a Quandary as to what to do Greg,we are Pensioners,and can't afford to Chuck,!!!! Money away as I am sure you appreciate Greg,,.The Car has no Trade in value as I enquired into this in its current state,and I wouldn't palm it of to anyone knowing the g/box is faulty.
The only option I see is to keep the Car and just use it on Short Journeys (20 miles),if you advise this to be ok
I deeply appreciate your time and effort to resolve this,,but reading forums this problem with auto gearboxes occur quiet frequently with Hyundai Coupes..The worrying thing Greg is I recently changed my Car for an AUTOMATIC Hyundai Ix20.
2011 Reg lol (the reason for this was my Wife will only drive Automatics)
HELP!!!!! ����

Hi Bernard .

Did you at all recheck for transmission malfunction codes .

Has any warning light come on at all when the engine is running .

Oh which engine do you have in the Coupe 1.6. 2.0L or the 2.7L


Customer: replied 2 years ago.
The Car was taken to Hyundai Dealers and checked with their diagnostics...the only light coming on is the engine managment
light,which governs emissions,this has occurred before and the 2 sensors were cleaned and the problem cleared,but it does come back on again after a while,
The engine is 2.0 L

What was the codes Engine management codes can affect transmission operation .


Customer: replied 2 years ago.
I will put this question to the engineer tomorrow,
Thanks again for your on going attention to this problem
Kind regards

Thank you Bernard will look out for your response with the codes .


Customer: replied 2 years ago.
Greg Hi
All the codes were deleted,and the Car was driven a distance,,codes??? We're restored as per adaptations???.
Mechanic has assured me it can't be an electrical problem...Either as the box had been laying around for sometime perhaps something has become seized slightly,and might free after a while.The other thing he said Greg was it could be temperature related to pressure in that when the box gets hot and expands!!!! there is a larger void thus making the pressure less.
I think the only option now as we are at our wits!! end with this,and the Car is of no value,is to just use it on Short Journeys and hope the problem might rectify.
Many thanks Greg for your time and effort you have put in to this for me
Kind Regards

No warranty on the box you changed ??

Could be it as your mechanic said .

Don't think driving it will change anything .


Customer: replied 2 years ago.
Hi Greg
Yes there is a warranty on the box,but the cost of swapping them over wouldn't be worthwhile ,as there would a loss in the difference of swapping.
Going back to the engine management light,,it seemed this morning when my Wife drove the Car and the problem occurred again she noticed that the engine magagement light had come on again,,,So what voiod be causing this,,would it be advantageous to change the 2 sensors that control the emissions.....On the diagnostics this was the only code showing a fault.
Thanks again for the attention you are giving this problem

See if you can get hooked up and let me know what the codes are for the engine .

Same transmission code come back.


Customer: replied 2 years ago.
Have to contact the mechanic ,and arrange this Greg,,,
He is away for a few days will get back A.S.A.P
Explain same transmission code comeback please. Do you mean the same engine code as before after you hook!!! up
Thanks again Greg
Customer: replied 2 years ago.
The lumber code for engine management light (which is remaining on still ) showed fault on diagnostics, but I was advised that this wouldn't affect g/box
Greg your advice please.I have ordered an additive called Lucas Transmission Fix,American origin,allegedly good for seals,and smash changing of gears in Auto boxes,it is supposed to lower temperature of the g box oil,and generate more pressure to enable smoother gear changer.Have you any experience of this type of product.
Hope I am still eligible for advice from you.
Many thanks Kind Regards