5th Gear and 6th Gear 0% throttle to 80% throttle gear crunch?
 

Hi Guys

Just picked up my new GT manual yesterday and have been enjoying the cars sublime handling prowess, and the cars impressive styling.

One minor issue I've noticed is that in 5th and 6th gear (gear is fully engaged already), when I'm cruising at 0% throttle at about 2000rpm and then I apply 80-100% throttle suddenly, I hear a metallic crunch noise coming from what sounds like the clutch or gearbox just as the car is about to accelerate.

Happens pretty much every time I replicate the situation, although if I gently ease onto the throttle instead, eg. throttle it up from 0% to 80% gradually over a second or 2, no such issue.

No other issues with gearbox or clutch Im aware of..

Has anyone experienced this? Can a couple of people try this and let me know what happens?

Cheers

Congrats on your purchase.
I know I'm not answering your question, but I would not go 80%-100% throttle at 2k RPM. That just seem too painful to do...
I would at least set the gear to 3k RPM or higher before going 80%-100% throttle.

I think you are at too low rpm for the 6th gear . Every gear has to be selected with the right engine rpm. Practice

Is this your first manual if yes that would explan .

are you sure its a sound coming from the gear box or somewhere in the back/bottom of the engine ?

I have this issue as well which the service boys are looking at today but mine happens in gears 3 & 4 as well and sometimes i get a pop that follows after it

Knocking and pinging could sound like crunching. This puts lots of stress on the engine.
Rather than trying to type it all out I'll provide this link. http://www.aa1car.com/library/spark_knock.htm

You should avoid that type of acceleration from that rpm in the higher gears like 5-6.
It's just fine to cruise without any hard acceleration. If it sounds like it's bogging, it's lugging the engine.

What octane level are you using? Are you still driving on the dealer fill?

i also suspect pinging

I'm not sure if dealer fill up my tank for me as it only a half fill but I recall reading somewhere that from factory its half fill?

I didn't take noticed as I was breaking in quite softly until later on which I was filling the car with 98ron (93 for you guys in the states) and thats pretty much when I took noticed

Another guy I know also had pinging from day 1 as well with factory/dealer fill

appreciate the response guys,

it does sound like gears or a clutch gnashing with another surface, and from what i know it doesnt sound like pinging, from what i understand pinging is sounds a bit like marbles hitting other marbles, whereas the sound im experiencing is quite loud, much louder than pinging (which ive experienced in a prior car), and the sound only occurs just as the engine starts to accelerate

i feel its drive train related as the sound happens at the exact time that the engine is about to start to rev upwards, i.e it would be the same time that you would expect a loose drive shaft to knock or something like that, but instead i get this kind of clutchy/gearboxy gnashing / crunch sound.

also with the engine pinging, id assume id hear it after i begin full load acceleration, but the sound only happens just on the initial applicaiton of the throttle. once continuing application of throttle no such noises are apparent

only reason why i am applying this kind of load in such a high gear is just to diagnose any potentially issues with the car and help it break in at a different load / rpm combination

thanks again for the responses so far though!

I'll third the "ping" notion.

your pretty much getting the same issue that i'm getting and now after i got it back from the service centre and foreman giving it a road test, its a lot more noticeable and worse.

what happens if you back off the throttle and then accelerate again? do you hear it? and if so, does this noise comes back intermittently ?

Your best bet is to call your service centre and let them diagnose the issue and raise it up with toyota aust. I do think its pinging but i'm no Toyota mechanic.

hi sho,

i haven't tried again since then, but next time im on the free way ill give it a try... i also noticed it doesnt need to be 80% throttle for it to occur, something like 60% throttle can cause the grind/gnashing noise...

yeah I'll give my service centre a call, better i do it early so they know it was faulty from shipment if there is an issue

cheers mate