Diagnosing an issue....need help.
 

Hi,
Just wanted to state one thing before i get into the issue, I'm in no way a car expert. So advice in simple terms would be much appreciated.

I have a 2003 G35 Sedan Automatic. Have about 210,000 kms on it.
About 2 days ago I started noticing that the car wasn't shifting too well. It was holding all the gears longer. The gears wouldn't shift as quickly as they usually do. I mean at about 120 km/h speed the engine would be revving as high as 5000 rpms.

Tonight, on my way home the car suddenly wouldn't pick up any speed at all. I was luckily coming downhill so got out of the way of traffic. But it would rev, but wouldn't pick up speed at all. And if i pushed the gas a bit too much, the whole car would shudder.

I tried to put it in the manual mode, but the car display still said "D".
Eventually when i got home i turned the car off and then started it again. The "AT CHECK" light flashed a few times and then turned off. I tried to shift the car to manual mode again and it worked fine.

I didn't try to drive it again cause I'm afraid I might be messing something up.

Anyone have any idea as to what might have gone wrong?? I've heard the word "transmission" being mentioned when i spoke with a friend and it's got me sweating buckets cause i know transmissions issues are VERY expensive to fix.

I even read about a Throttle body problem on these forums, but not sure if my issue is the same.


Any insight/help would be greatly appreciated!!


Thanks in advance!

Whens the last time all the fluids were drained and redone?

The transmission fluid was flushed at about 145,000 kms. The car is at 206,000 kms now.

^ What fluid was used?

Not really sure what fluid was used. It was done at an Infiniti dealership. A proper "flush" was done.

Should be on the receipt, but since it was done at the dealer most likely it was Matic-S(replacement for matic J) which is the correct fluid.


When the AT light turns on, does it store the code?

Something does sound fishy with the Transmission, do some searching on this site and see if anyone had these issues.

Sorry I could not help more, Good luck!

Thanks. I will continue to search.

Will take the car to the dealership as soon as possible. Hopefully they won't take me to the cleaners.

Another piece of added info....
I took the car out this morning. It's picking up speed now, but still shifting too late.

That's really the only advice I could give you. Where are you located?

They will. There's no two ways about it.

You could always have it done by another transmission shop though.

could be a tired torque converter... Sounds like your engine is fine, and old fluids would hurt the performance of the trans but it wouldnt stop it... it makes me think that its the piece between the engine and the trans...

I live in Richmond Hill.
I'm not gonna drive the car and just let it sit on the driveway till Tuesday. Will take it in there. If they say its the tranny I will take it elsewhere. Hope they don't mind cause I'm not paying $5000 for them to fix it.

So after doing a bit of reading I have come up with some explanation.

The complete failure that happened last night was a "fail safe" lock system and it locked the last gear it was in which I'm guessing was 2nd. After turning the car off and then on, the fail safe disengaged and the car was picking up speed as before.

I still have to find the main problem. Hopefully it's something smaller like "reprogramming the transmission control module" but that's just a hope.

Will find out on Tuesday what I'm gonna get hosed for!!

^^^^

Post this over in the Canadian section...

Man I sure hope ur wrong about the $35 bills part!!

You want me to post the whole thread again in the Canadian section??