Gearbox (clutch?) trouble + engine question

[Yonzie]

Hey guys.

When I start up my car, the idle is at 2200RPM after it heats up a bit, it falls to 1000RPM... I've been told this is normal, but it's annoying... Is there any way to change this other than swapping out the engine for a newer one like the 20v?

Now, on to the meat of my troubles:
When the engine is cold, the gear shifter is in neutral, and I release the cluch, it's like the car very very slowly creeps forward. If I release the clutch quickly, there's an audible "thunk" sound. After a bit of warmup, when the engine is at maybe 2000RPM, I can make it fall to 1500RPM by doing the same.
This is a recent development over the last ~150km (mostly city driving).

The car has 240k km on the odometer, and according the the previous owner, the engine is the original one. Although I didn't think to ask him, I suspect the same is true of the gearbox.

Any idea what's wrong and what I need to do to fix it?

[Aico]

OMG you don't know why the rpm's are higher when the engine is cold?

And the gearbox is somehow broken. Could be just the bushing or other things. Hard to say.

[Yonzie]

Aico Wrote:OMG you don't know why the rpm's are higher when the engine is cold?

Yes I do, still, it's annoying, and it apparently doesn't have issues idling at less RPM so...

Aico Wrote:And the gearbox is somehow broken. Could be just the bushing or other things. Hard to say.

Damn... I guess this is something that'll take at least a few days to fix at a dealership?

[Knudsen]

Its possible that its annoying that it idles @ 2200 rpm when cold. But if it doesnt, you risk that the engine stops or simply wont idle... The 20V does the same, perhaps not @ 2200 rpms, but its defently has a higher idle when cold. Every 4AGE that i know of, does excactly the same.

As for your gearbox, i think its easyer to find another one... Look at toyotaextreme.dk in the market, there was alot of ae86 parts for sale the other day.

[Mux213]

There is a bit more to the 2200 rpm thing, the car will idle just fine when its cold and at lower rpm, don't know how much lower though

But the engine will heat up faster meaning much less wear on your engine, if I were you Yonzie, I'd keep it like that. Toyota did this for a good reason, its one of the reasons why your engine at 240k is still running just fine, especially if you do lots of city driving. I drive my car every day, it takes about 2 minutes for it to drop from 2k to about 600 rpm which is on the low side, I need to alter it to run at about 700 rpm when warm. It nearly stalls when idling once warm.

During those 2 minutes I'm driving 90% of the time so my rpm's are above 2k anyways, I only notice it idling high when I stop at a traffic light.

As for your gearbox, yes its very likely that its the original gearbox, when treated right they will live the lifetime of the car, or almost anyways I'm no expert but it sounds like your synchro's are on their way out. They may not be disengaging completely hence some power from your engine is still going into the drive line. Easiest solution is probably to just find a second hand gearbox with less milleage and swap it over. I dont know about Denmark but in Holland you usually get a discount if you hand in your old gearbox at a scrapyard. Fixing up a gearbox can get way more expensive then its worth (unless you have a friend who's willing to take the gearbox appart and put it back together for you for free). Also unless you rebuild your gearbox completely there is a change the next problem is just a couple of k away.

Swapping a gearbox should be easy as hell for any experienced mechanic. Offcourse its always smart to drive past a toyota dealer and ask a mechanic to diagnose the problem first, might be I'm completely on the wrong track

[Yonzie]

Knudsen Wrote:The 20V does the same, perhaps not @ 2200 rpms, but its defently has a higher idle when cold.

Hmm... Interesting...

mux213 Wrote:But the engine will heat up faster meaning much less wear on your engine, if I were you Yonzie, I'd keep it like that. Toyota did this for a good reason, its one of the reasons why your engine at 240k is still running just fine, especially if you do lots of city driving. I drive my car every day, it takes about 2 minutes for it to drop from 2k to about 600 rpm which is on the low side, I need to alter it to run at about 700 rpm when warm. It nearly stalls when idling once warm.

During those 2 minutes I'm driving 90% of the time so my rpm's are above 2k anyways, I only notice it idling high when I stop at a traffic light.

My issue is that my first two minutes are mostly spent getting into traffic and waiting at a traffic light, and I cant help thinking that everyone else thinks my lovely 86 is broken.
Interesting thought about the heating - hadn't thought of it like that.

Knudsen Wrote:As for your gearbox, i think its easyer to find another one... Look at toyotaextreme.dk in the market, there was alot of ae86 parts for sale the other day.

mux213 Wrote:As for your gearbox, yes its very likely that its the original gearbox, when treated right they will live the lifetime of the car, or almost anyways I'm no expert but it sounds like your synchro's are on their way out. They may not be disengaging completely hence some power from your engine is still going into the drive line. Easiest solution is probably to just find a second hand gearbox with less milleage and swap it over. I dont know about Denmark but in Holland you usually get a discount if you hand in your old gearbox at a scrapyard. Fixing up a gearbox can get way more expensive then its worth (unless you have a friend who's willing to take the gearbox appart and put it back together for you for free). Also unless you rebuild your gearbox completely there is a change the next problem is just a couple of k away.

Swapping a gearbox should be easy as hell for any experienced mechanic. Offcourse its always smart to drive past a toyota dealer and ask a mechanic to diagnose the problem first, might be I'm completely on the wrong track

Ya, I'm just kinda nervous about buying another high-mileage gearbox... I've heard about getting discounts when turning in an old gearbox in exchange for a rebuilt one, but the 86 is quite rare, so I doubt there are anyone in Denmark providing that service...
Apparently, there are quite a few used ones available, but they all have 200k+ km on them (or just '999'), or are located as far away from me as possible, while still being in Denmark.

Oh well... Guess I'll have to get it swapped out. Thanks a lot for the help everyone.

[Widar]

My hachi does the same thing, idle at about 2000-2500 when cold. Falls when it's getting hotter.
Same thing with my beamer, higher idle when cold.

Nothing to worry about!

[zeetee]

yup mine too....auto heat up i guess.....

[Crimson]

prob. is the choke, my mom.s car dosn't have an auto choke, its anoying and if u forget to flip the choke u just Can't start the car and if u flip it off when the car is not yet warm it will just quit! (very anoying when u are standing at the stoplights and u can't start your car b'cos u forget u turned the choke off)
my 205 has the same, more revs after u start, thats the auto choke.

[Mux213]

Yonzie,

Swapping in another hi mileage gearbox in is asking for trouble, maybe see if you can get a local gearbox rebuilder to take a look at it then..