Hello, I was driving home late last night and 2 miles form my house I was decelerating and had 2 hard downshifts then it clunked into 2nd and third, but would not shift into 4th. Instead of shifting into 4th it would make a clunking sound and the car would shake like a bad shift in a manual car, but would not upshift. I drove the car home the rest of the way in third gear while staying less than 25 mph. Each time it would go more than 25 it would start shaking and thunking like it was trying to upshift but it would not.

Does this sound like the Transmission failed, or maybe the synchros or torque converter or something like that?

Any feedback would be greatly appreciated, I know I'm going to have an expensive repair bill but I am trying to find out exactly what it is to not get ripped off more. The car is a 2009 A7 g37 with 124k miles fyi.

 

Throwing any codes? When was the last time the fluid was changed; out of curiosity? If it's the transmission, I'd take to a dedicated shop and see if they can piece it together (i.e. torque converter, clutch packs, valve bodies, etc...).

 

I had the transmission fluid changed less than 15k miles ago. No codes at all showing.

That's what I was thinking, to take it to a transmission shop and hopefully its anything but the transmission needing replacement.

Have you heard anyone else having this issue?

 

Does it make any noises? When mine went out (clutch packs) it was whining.

 

Not loud noises unless it is going to shift into 4th gear. It wasn't making a loud whining noise if there was one.

 

Cool. Glad to hear the maintenance was done on it at least. See what a shop says then I'd go from there. replacing an individual component would definitely save you some heartache in the financial department.

 

Kind of unrelated but say I need to have the transmission replaced, what would be the value of the car if I traded it in with the messed up transmission? It is an 09 with 124k miles and otherwise in good shape.

 

Just an update, I started driving the car today before getting it towed to make sure the issue is still there, and lo and behold it shifted into 4th and 5th gear completely fine, with no hard shifts or hitches or anything at all. Even in D mode it was completely fine.

I'm thinking it may be a transmission fluid leak where because it was sitting flat the fluid was able to properly lubricate things where it wasn't before. I really don't know, but I'm going to take it to a shop to have them take a look at things.

Do you think a regular mechanic or a transmission shop should look at it? The only code showing is a pending code for needing a MAF cleaning/replacement.

 

I would. If you could, take to a shop that has experience with these cars; since it's a closed system and they'll have experience with it. It could be a leak somewhere. I had the same thing with my old Mazda and now that you mention it, the car went into limp mode and wouldn't go past 3rd when the car detected low fluid. Dealership wanted a new trans but an independent shop just added new fluid and $80 later I was on my way.

 

Gotcha, thanks. I talked to my local mechanic and he said my mass air flow sensor needs to be replaced, as I have a pending code of the catalyic converter not working correctly, and it made the car enter limp mode. I don't think it has to do with the transmission because I drove it and it was shifting fine, it had just entered limp mode.

Does that make sense to replace the MAF sensor? Also he quoted $300 for the part from the dealer is there anywhere to get it cheaper that you know of?

 

Oh absolutely....I'd even recommend cleaning the ones you have with MAF cleaner from advanced auto or something. If it's a cat. converter issue, It might still be covered under warranty. If not, HyperMotor sports on Ebay have a good selection of used stuff for cheap.

Great deals in mass air flow sensor from HyperMotorParts | eBay Stores

 

I mistyped when I said catalytic converter, the code was for the mass air flow sensor, which is why he said to replace it.

Thank you for the link on that site. My mechanic said the parts from online don't work the same as from a dealer, which I think is just because he is old school or people buy from sketchy online retailers. Would that site be legit? I just don't want another issue down the line, thanks.

 

100% feedback and I just ordered $150 in parts less than 3 minutes ago lol.

I'd seriously recommend cleaning them first...spray and leave them alone to dry. Also, clean the throttle bodies as they might be getting stuck from build-up.

Edit: I understand why the mechanic wants to use dealer parts but you're paying 5x the price...just get used ones from a reputable seller. You could even buy a whole assembly from a user on this forum if you desired.

2nd Edit: If part is defective, follow the policy of the seller and return the part. Ebay will get you the refund.

 

Good luck with your issue(s), it does sound like that limp mode from throwing the CEL was what you experienced. Hopefully this story continues it's positive spin, keep us posted!

 

I've always used this for cleaning MAF sensors:
You can get it at any O'Reilly, AutoZone, etc...

If your cat is still throwing codes, it's probably an O2 sensor; there is a sensor upstream and downstream of each cat (4 total), and the code will tell you which one it is.

Another vote here for Hyper Motor Parts. I ordered a used steering rack from him a couple months ago; it came exactly as described and it works perfectly. BTW all his parts are pulled off wrecked G37s, so you're getting original factory parts not aftermarket.