Strange Noise Coming From Gearbox

[baz1631]

was under the car the other day and noticed a very faint kind of "ringing" noise coming from what I think was the gearbox bell housing. Could this be a tell-tale sing of dreaded DMF failure? or something else? Hopiing for a non expensive fix !!!!!!

[Big Kev]

was under the car the other day and noticed a very faint kind of "ringing" noise coming from what I think was the gearbox bell housing. Could this be a tell-tale sing of dreaded DMF failure? or something else? Hopiing for a non expensive fix !!!!!!

As quoted previously by Oor Bothy, check the exhaust heat shield unnerneef Baz....is it rattling off the bulkhead or underside? Simple checks first, muckeroony.

Big Kev

[baz1631]

Hey Big Kev!!! Howzitgawn? Naw, ah therw the heat-shield aboot a year ago, when it wis dion ma heid iin wi' the rackit it wis makin' Whits next?

[Big Kev]

Hey Big Kev!!! Howzitgawn? Naw, ah therw the heat-shield aboot a year ago, when it wis dion ma heid iin wi' the rackit it wis makin' Whits next?

Check if there's a wee person underneath in a cassock pulling a rope...not called a bell housing for nothing, ye ken....

[baz1631]

Not quite the answer I wis lookin' fur BK, but velly funny, ha ha

[Tech01]

was under the car the other day and noticed a very faint kind of "ringing" noise coming from what I think was the gearbox bell housing. Could this be a tell-tale sing of dreaded DMF failure? or something else? Hopiing for a non expensive fix !!!!!!

Getting back to your original question . . . What year is your D4D?

Chris

[baz1631]

HI CHRIS, its a 2002 5door model (much to Bothys disgust!).apart from that, there is also a h*** of a "flapping "noise when accellerating but seems to dissapear for a wee while after a long run of about 50-60 mls then returns with normal town driving. (i only do about 20-25 mls aday!) and most of it in 3rd or 4th gear.

[Big Kev]

baz....did you not have a new turbo fitted a while back.....? Really hope it's not your DMF....YOU'VE HAD YOUR SHARE OF GRIEF WITH THAT CAR, MATEY.

[baz1631]

Tell me bout it! Its nothin' but a money bucket, i certainly wont b gettin another Toyota, thts for sure.If its the dmf Iget it done an' thats it.......................NO MORE!

[Tech01]

Baz,

Thanks for the date for the RAV, which is a 4.2.

I'm interested in the "flapping noise" . . . When does this noise happen? In which gear? Heavy or light throttle? At what RPM? What happens to engine power when it occurs - eg does it fluctuate?

Bit more info, please.

Chris

[baz1631]

hI again, it usualy happen s when eg: changin down to 2nd going up hill any excess throttle to get more speed up hill and it starts., (the neighbours are getting used to it now!) when getting up speed at about 1500-2000 rpm. Once in higher gear its ok and runs fine till u want to use more throttle. Its simmilar to the noise of a blown exhaust ,the faster u go, the more noise comes out. Hope u can make some sense of this!!!

[Tech01]

Good morning, Baz

You describe what I had a few years back - noise like a leaking exhaust, but 'flappy', and at high throttle settings. Mine turned out to be a blocked cat (first exhaust box). The tiny ceramic honeycomb inside was 80% choked with soot.

Test for this: Remove the exhaust system (easy to do), after the first downpipe (i.e. cat and everything after it). Try driving the car, and see if the problem disappears. (It will drive surprisingly quietly like this. On diesel turbos, the turbo smooths out the exhaust pulses, and quietens things down.)

If this is the problem, you can peer into the cat box and look at the honeycomb. If it's choked, you'll see it. Remedy is either to replace the cat box, or remove its contents (poke out with a long cold-chisel; it crumbles). Obviously you shouldn't do the latter, but . . .

Let us know what you find.

Chris

[Tech01]

And, your original question about the jingling noise . . . Does sound if it could be the DMF beginning to go. Do you also have less than perfect clutch take-up, eg difficulty hill-starting, what feels like clonks and backlash in the clutch as you change gear, or any kind of bump as you go from drive into overrun or vice-versa?

DMFs usually fail slowly (you get a fair bit of warning), but not always. If it has gone, I personally suggest you don't go to the huge expense of another (these can fail too), but simply fit a Blueprint SMF kit. Full details elsewhere on the site.

First, though, fix the other problem, because it will be masking everything else, and sounds pretty intolerable.

Chris

[Big Kev]

And, your original question about the jingling noise . . . Does sound if it could be the DMF beginning to go. Do you also have less than perfect clutch take-up, eg difficulty hill-starting, what feels like clonks and backlash in the clutch as you change gear, or any kind of bump as you go from drive into overrun or vice-versa?

DMFs usually fail slowly (you get a fair bit of warning), but not always. If it has gone, I personally suggest you don't go to the huge expense of another (these can fail too), but simply fit a Blueprint SMF kit. Full details elsewhere on the site.

First, though, fix the other problem, because it will be masking everything else, and sounds pretty intolerable.

Chris

Sound advice on the order of repairs, Baz, and more so on the SMF as opposed to DMF route probably.....was astonished to find oot on here that an expensive DMF replacement can also go pearshaped, and sometimes at much lesser mileages.

So investigate CAT, only replace flywheel if totally necessary.......then......get rid.....?

Big Kev

Big Kev

[baz1631]

Thax for yer advice gentlemen, I'll get into the cat later in the week and check it out,and hopefully that'll be that! Nearly forgot..................... Goodmorning!

[baz1631]

Please excuse my ignorance of mechanical parts Chris, but is the cat BOX different from the cat converter?

[Tech01]

Baz,

'Cat box' and catalytic converter are one of the same - sorry if I confused - and is the first exhaust box down from the engine.

Chris

[baz1631]

hi C hris how u doin'?, am I right in saying the cat box u refer to is attached to the manifold? or am I looking @ the wrong part? and if so can I remove it without taking off the manifold?sorry for being a nuiusance but the Haynes manual for my car isn't much use!

Baz

[Tech01]

Hi Baz,

OK . . . From the engine, you go manifold, turbo, and then a down-pipe. No need to disturb any of these. The cat is the first 'silencer' box, which has a heat-shield around it. It is positioned next to the front half of the prop-shaft.

Just ahead of the cat is a bolted flange joint, linking it to the down-pipe. You should undo this joint, and remove all the exhaust that follows it, which includes the cat. Test-run the car with just the down-pipe in place.

You need to work safely on all this, so it's best to find a helpful workshop/garage. Using a professional ramp/lift makes exhaust removal and refitting very straightforward.

Chris

[baz1631]

Thanx Chris, I only ask these ouestions sp I remove the right part.my H manual shows a pic of 2 cats? and dose'nt say if its petrol or diesel and as I said its not very precise in description, apart from thet I think Dementia is setting in!!. Many thanx for all your expert advice (and everyone else!)Thats what I appreciate about this site.Honesty and sound advice. Something u dont always get from a garage!Cheers gentlemen, and good afternoon

[baz1631]

JUST had a look under the bonnet and saw exhaust coming from around the manifold/turbo/downpipe area! so might not be the cat after all...i think! Anybody know where I can source a new front end down-pipe without going through Mr T ?

[Davrav]

JUST had a look under the bonnet and saw exhaust coming from around the manifold/turbo/downpipe area! so might not be the cat after all...i think! Anybody know where I can source a new front end down-pipe without going through Mr T ?

JUst go round and tighten any bolts before you go looking for a down pipe Baz - could just be something loose. Didn't you replace the turbo recently?

[baz1631]

Hi D.rav! yea ,got the turbo replaced lasi Nov, (intrestingly around that time this b****y flapping noise began!) Will have a look @ all the bolts an see if theres anythin amiss! Thankx for the obvious tip.I lay nder the car and got my son to rev it pretty hard and lo an behold a burst of exhaust fumes came flying oot o' the top part of the exhaust (couldn't see exactly where but it seems /sounds more like a gap in the join rather tha the kind of "putt put t " sound u would get with a hole in the pipe. Will have a closer look @ the week-end!Cheers , and thanx again for ur advice

BAZ.................

[Davrav]

If you should need a down pipe Baz, there's several different ones available on e-bay [mostly pattern parts] all around £40 ish......................

[baz1631]

Hi again. had a quick look @ the join between the turbo and the manifold and found one of the bolts hadn't been fuuly tightened! and also the other..bolts (3?) needed further tightening! or is there 4? todays question is ,is there meant to be a gasket/sealant between the join?