Avensis Throttle Diaphragm

[barndoor]

Had like a throttle Hesitation/Judder when Accelerating/De-celerating, On my S 98 Avensis 1.8GS, after a little investigation, noticed there is a linkage on left hand side of inlet manifold, Moved by a Diaphragm fed from vac pipe on inlet, oppsite to air filter, did not seem to be now working, had been working, stop screw had made a mark on stop, but now dull, tried it from cold to hot, revving, air con on, did not move, so took it for a service at local toyota dealer, but forgot to mention what i had found, asked when picking up, No sir, nothing unusual found, told them what i had found, mechanic came out tested it, Diaphragm Holed, checked on their system, "Sorry sir, you have to buy complete inlet manifold assembly, to replace Diaphragm, quoted nearly £350 inc labour to replace,

Mechanic did say, it opens a butterfly valve into each cylinder, and i should notice a big improvement if changed

Thought of writing to Toyota and having a good moan,

Any one had same prob or similar?

[05D45]

There's something going on with my own Avensis (2005 2.0 D4D Hatch) where there seemed to be a bit of judder if just trying to maintain a steady speed at low revs (1200-1800 range) or slowly accelerating past this range. It's at the main dealer at the moment, but don't know if they'll find anything. I'm a bit concerned that it's one of those things that might not show up easily on diagnostics or whatever.

I'll post something up when I get it back.

[Big Bad Bob]

Had like a throttle Hesitation/Judder when Accelerating/De-celerating, On my S 98 Avensis 1.8GS, after a little investigation, noticed there is a linkage on left hand side of inlet manifold, Moved by a Diaphragm fed from vac pipe on inlet, oppsite to air filter, did not seem to be now working, had been working, stop screw had made a mark on stop, but now dull, tried it from cold to hot, revving, air con on, did not move, so took it for a service at local toyota dealer, but forgot to mention what i had found, asked when picking up, No sir, nothing unusual found, told them what i had found, mechanic came out tested it, Diaphragm Holed, checked on their system, "Sorry sir, you have to buy complete inlet manifold assembly, to replace Diaphragm, quoted nearly £350 inc labour to replace,

Mechanic did say, it opens a butterfly valve into each cylinder, and i should notice a big improvement if changed

Thought of writing to Toyota and having a good moan,

Any one had same prob or similar?

I have seen the linkage fall off before but not the diaphragm split I normaly test them with a midi vac but if not the system only works when throttle is fully open when not driving the car.

I would get her to operating temp and then blip the throttle fully open (quickly) and watch for the movement of the valve.

Have you got any vacume at the unit? when the engine is running you should have vacume there and throttle open it should all go

when these units fail it makes them very flat above 3000 rpm and lack power

Hope this helps

[Big Bad Bob]

There's something going on with my own Avensis (2005 2.0 D4D Hatch) where there seemed to be a bit of judder if just trying to maintain a steady speed at low revs (1200-1800 range) or slowly accelerating past this range. It's at the main dealer at the moment, but don't know if they'll find anything. I'm a bit concerned that it's one of those things that might not show up easily on diagnostics or whatever.

I'll post something up when I get it back.

get them to check the flywheel they give vibration at 1200-1800rpm and judder when pulling away

[05D45]

get them to check the flywheel they give vibration at 1200-1800rpm and judder when pulling away

Thanks Bob, much appreciated. I'm in the unenviable position of having bought the car from a Honda dealer who has passed the car back to the Toyota main dealer since some warranty remains on the car. I just hope that, A) they're aware of the flywheel issue and, B ) they're not adverse to fixing such a big thing if it does turn out to be the problem.

They have had the car for comming up to a fortnight at this stage and the've told 'my' dealer that they're waiting on a part. Hopefully it's a spanky new flywheel they're waiting for and not the luggage tie-down that was missing from the boot!!

Does changing the flywheeel fix the problem permanently?

Thanks again...

[Big Bad Bob]

get them to check the flywheel they give vibration at 1200-1800rpm and judder when pulling away

Thanks Bob, much appreciated. I'm in the unenviable position of having bought the car from a Honda dealer who has passed the car back to the Toyota main dealer since some warranty remains on the car. I just hope that, A) they're aware of the flywheel issue and, B ) they're not adverse to fixing such a big thing if it does turn out to be the problem.

They have had the car for comming up to a fortnight at this stage and the've told 'my' dealer that they're waiting on a part. Hopefully it's a spanky new flywheel they're waiting for and not the luggage tie-down that was missing from the boot!!

Does changing the flywheeel fix the problem permanently?

Thanks again...

I think the flywheels have been modified they have them in stock so it should only take a few days to get in ? do not understand why they need the car so long

[05D45]

I think the flywheels have been modified they have them in stock so it should only take a few days to get in ? do not understand why they need the car so long

Got the car back and no change at all. I'll bet my bottom dollar they were waiting for the console door that was fixed when I got it back. Mentioned on the phone this morning that I'd been advised that this could be the flywheel, but the guy told me there were no problems with 05 Avensis in that regard (He reckoned that it was around 01). I think he's referring to the collapsing flywheel issue that I've read about on the earlier 'new-shape' diesels. Am I right in thinking this is a different thing altogehter? I'm taking him for a drive in it tomorrow so that I can demonstrate...

Thanks a million...

[05D45]

And it seems after all that it's down to a couple of buckled wheels... No impact damage on the front of the wheel, but when you see it spin from behind when the car is on the ramp it's like an egg.