Really, really annoying engine rattle..

[Anonymous]

I am also having this problem. At about the same revs. I was planing on using my mates pit tonight. After reading a number of post on this subject all I was going to do was remove the two lower heat shealds on the underside of the exhaust. They are both quite rusted and in bad shape. I think I may need to use an angle grinder or similar as described in most of the posts.

One question really... What are going to be the implications of removing these shields ? Apart from maybe burning some long grass if I ever park in a field.   s:P s:P

[Anonymous]

Anyway, it's obviously on the intake side of the engine, right before the intake manifold and after the 90 degree intake pipe bend between the MAF/engine. I think it should be easy to find by feeling around with your hand (might wanna do it with the engine off the first time). There's only one cable in that area and only one moving thing  s8) s8)  Pulling that cable/bracket to the left opens it.

Or is it right in RHD cars...? Anyway, feel around and try to move things  s:lol: :lol: s:lol:

Thanks Tem, I'll go have a play!   s:D s:D

[spit]

Eko - I'm still not versed with hosting and posting pics, but its "pull to the left" on RHD cars too. Dead easy to find, but do it with a cool engine!

Aaron - this really does sound like a heatshield thing doesn't it. Keep at it, you'll find it. Back end of the main cat shroud is a favourite for looking solid but vibrating under load.

Longer shot, but you could also try the manifold heatshield - my spare looked fine - side bolts still in place - but the hole in the back half of the shield had rusted itself away, making the entire assembly loose.

[Anonymous]

I found it.   s8) s8)

[Anonymous]

Went in the pit last night and had a really good listen while my mate reved the engine. The niose was certainly not coming from the heat shields and appeared to be coming from the top of the engine somewhere ! Central ish, but hard to say left or right. Therefore I didnt remove the shields.   s:oops: :oops: s:oops:   We are now maybe thinking something like the timing chain is loose. Is this a possibility ? I have the workshop manual and it looks likie a major job to get to the bugger and do all the necessary checks on it.

Any advice ?

[Tem]

It's very hard to guess what the noise is through some text  s;) s;)

Yes, the chain might make some noise. 1ZZ also has a very loud valvetrain. Might even be the belt tensioner. Good news is that none are fatal, unless they get worse  s8) s8)

[philster_d]

It's very hard to guess what the noise is through some text  s;) s;)

See the matrix Neo!

[Anonymous]

Did you manage to sort this??

I have a very similar problem  when the car is cold.  I think it is coming from the main cat as when i put pressure on it and pushed upwards, it stopped.  i checked all nuts (very rusty) and they all appeared to be secure.

  s:roll: :roll: s:roll:

[markiii]

what oil weight are you using?

[Anonymous]

Using 5w-30w.

[Anonymous]

Think this is poor form to add links into other post but... just to let people know how I am getting on with fixing my rattle described at the top of the page !

 m http://www.mr2roc.org/phpBB2/viewtopic.php?t=8159 m

[Anonymous]

We have the exact same rattle so I'm reading with interest!   s:) s:)

[aaronjb]

Found the source of my rattle today.. couldn't exactly fix it, though, sadly.. but anyway, photos:

Gratuitous bum shot:


The offending heat shield is the one on the left in this picture - the top half of the shield appears to be part of the main CAT shield (but it's hard to see), the lower section is (or, rather, was welded to the exhaust just below the flexi section.. The welds break and, bingo, one rattle.


The weld is highlighted here in yellow:


Click for un-sized versions of the pictures.

I got one of the (very rust) bolts out nearest the flexi section, and the other almost out - stupid castellated nuts that round off and destroy themselves (they're meant to be 'use-once' I think)..

Went to ProTyre and got them to try grinding them off, before they realised that the upper section of that shield appears to be welded to the main CAT shield.

So they tried tacking the shield back on to the exhaust with an oxy torch and welding rod, but it wouldn't stay welded, so gave up..

However - my rattle appears to be gone, for now, just by removing all the bolts bar one.. How odd.

Looks like the lower and upper shields will have to come off with the aid of a grinder, when the CAT can be disconnected from the manifold and swung down a bit for easier access.

Bummer - still, at least ProTyre didn't charge me anything..

[spit]

Great that you've got it "sort of" sorted Aaron, and yippee - its nothing internal.

The heatshield bolt joins and tack welds are very poor in design and quality, especially when you consider the temperature trauma the shields are being put through. Its pretty inevitable that so many of us are getting these niggling rattles.

I've looked into mig welding mine back but it would require serious re-shaping to get enough material aligned - project for another day  s:wink: :wink: s:wink:  

Currently, everything is bound with that wonderful metal strapping stuff! It beats Rover dealership's approach to the same prob on the 21*'s a few years back - their cure was to rip the thing off completely  s:!: :!: s:!:

[aaronjb]

The bolts really are terrible - especially the larger ones on the CAT shield itself, which crumble to dust when you touch them..

It beats Rover dealership's approach to the same prob on the 21*'s a few years back - their cure was to rip the thing off completely  s:!: :!: s:!:

Actually, that's what I was going to do to this heat shield  s:oops: :oops: s:oops:   s:) s:)

[Anonymous]

Thanks for the pics!  

When you say welded to the exhaust, Would it be as a result of poor welding when an aftermarket exhaust is fitted?

I looked at where the exhaust connects and I think there was about 4 bolts around the pipe (left hand side of the car)?  All looked fine.  

Is it worse when you first start up?

[spit]

When you say welded to the exhaust, Would it be as a result of poor welding when an aftermarket exhaust is fitted?

The problem lies before any aftermarket exhaust.....the bolts and welds holding the shield are on the factory Cat. Changing the exhaust shouldn't affect these, although its feasible that handling when dropping the cat to fit the aftermarket exhaust may have exacerbated an existing problem.

I looked at where the exhaust connects and I think there was about 4 bolts around the pipe (left hand side of the car)?  All looked fine.

The link between cat and exhaust is a flange fitting with (two-bolt) compression plates on each side.  

Is it worse when you first start up?

Symptoms vary, but "yes" seems to be the general answer to this. Before everything gets warm and expands, theres more chance of it being loose and rattly. A more common symptom is that it seems to be prominent at certain revs when the shield resonates, and again when you lift off and revs drop through that range.

[Anonymous]

Top job Aaron   s8) s8)  . I can at least point my dealer to the cause now next time the car is in. Save's getting the usual response of 'we couldn't find the problem'.

Cheers dude   s:wink: :wink: s:wink:

[Anonymous]

Thanks Spit!

I'm not very good mechanically!

I take it the fitting i've been looking at is totally seperate then!

The reason I ask is i've booked the car in with the company who fitted my exhaust and now it sounds like it ain't something for them to sort!

Although I suppose they could weld it back together rather than Toyota?

[spit]

Welding might not work for the reasons Aaron and I have encountered. I've used the metal straps which have held pretty well for two years and 40000 miles. Your local garage may have some (narrow 5mm straps applied with a special tool to draw them tight and lock them off).

IMHO, if you're going to try welding, just replacing the existing tacks won't work. The only way to get a good result would be to drop the cat off the car, clean everything up and work the shield into a decent position to take a more substantial weld - a big job.

[Anonymous]

Thanks for all your help!

If it is that then I will ask then to knock the old bit off to stop the rattle and get a metal strap fitted (hopefully they will have something that can do the trick there)!

If it's not the same problem, I will try and get some pics of what mine is!

Thanks again!

[Anonymous]

sorry to sound so stupid   s:oops: :oops: s:oops:   but can someone label the parts shown in the photos?

[spit]

pm'd you matey

[Anonymous]

SORTED!!!!  s:D s:D  

Thanks all for your help especially Spit. It turned out to be the heatshield.  Where the nut joins the 2 heatshields together (To the right of main picture but mine was the other side of the heatshield).  Company who fitted my exhaust put a semi-circle clamp around it and hey presto!!

Thanks again,

Viggs

[spit]

"I love it when a plan comes together!" - especially when it doesn't cost a fortune  s:wink: :wink: s:wink: