How Do Replacement Exhaust Catalytic Converters Perform.

[Konrad C]

Hi. I am asking for advice about replacement catalytic converter.

How good are the replacement catalytic converter compared to the original.

Basically I found an exhaust blow near the front of the pipe just before the first of the rear silencers, after the catalytic converter. The bolts at the joint between the catalytic converter and the rear exhaust are practically fossilized.

I have an angle grinder and various other tools to try and split the pipes. The reason is that the catalytic converter on my car is fine and the rest of the rear is shiny with only the welds showing a bit of rust. That is the gutting thing is that system is 16 years old and the rear looks new apart from that pipe.

I noticed that Euro car parts sell the complete exhaust in 3 parts - the front pipe is stainless steel made by React £21.94, so is the catalytic converter. There are 2 catalytic converters in the catalog £55 non type approved and £86.40 Type approved.

The rear exhaust is Klarius £59.27. These prices are as good as the internet and I can pick them up immediately.

Am I better off buying the complete system, going to a fitter (not really keen), or fitting the rear system only ( corroded nuts and bolts), and keep a working cat.

I have read up on the type approval and non type approval systems. This effects cars made after March 2001 (51 plates). My car is older. I have been told that the non approved cats work okay for about a year then struggle after. Is this true?

Just need other experience before doing the work.

Konrad

[Konrad C]

Here are pictures of the rest of the system.

Note that apart from the the small section which joins the cat, the rest is in fairly good condition.

The joint may split, but it does not look good. It looks like a complete new system.

Going to get a second opinion, but your opinions are welcome.

[Konrad C]

I made some further enquiries regarding exhausts, and it seem that they now use aluminium which prolongs the life.

Parts now ordered and still cheaper than taking it to a fitter who will charge £300+. I had to change the part number as one of the parts is for the vvti.

I have done lots of exhausts including a Ford Galaxy people carrier.

This is my first with this car since it is the original exhaust. Hopefully fitting will be a breeze.

[Harry Carri]

Hi,

That looks familiar, my car failed MOT at end of July with amongst other things an exhaust gas leak from the joint between the section with the cat in the centre and the downpipe from manifold. Bolts and joining surfaces completely crusty. I had both sections done by my local garage and the section with the cat was £85. They tend to use blueprint parts but I don't know for sure where my exhaust sections came from. That was their recommendation and runs nice and quietly now.

By now from your post that you have chosen and ordered your parts so job done.

[Konrad C]

Hi,

That looks familiar, my car failed MOT at end of July with amongst other things an exhaust gas leak from the joint between the section with the cat in the centre and the downpipe from manifold. Bolts and joining surfaces completely crusty. I had both sections done by my local garage and the section with the cat was £85. They tend to use blueprint parts but I don't know for sure where my exhaust sections came from. That was their recommendation and runs nice and quietly now.

By now from your post that you have chosen and ordered your parts so job done.

Hi Matthew

I wish I was near your area, as I would have got my exhaust from your garage. Here's why.

Got the parts today, and on checking and measuring the exhaust, the supplied catalytic converter is wrong!

The centre/rear exhaust is correct and so is the front pipe, but the catalytic converter is 102/103 cm long, whilst my cat is 95/96cm long. The other issue is there is a threaded hole for a sensor. My car does not have this. This cat must be for the vvti. Either that or Euro car parts/React catalog is wrong. I need to know if the the other catalytic converter on the catalogue is correct.

Also what is the real difference between type approved and non-type approved catalytic converters, apart from testing?

Remember, my car was made in 1998 and type approval rules came in from 2001. I can assume that both types are made of the same materials and in the same way. The attached pictures show the threaded hole and the complete system.

I am returning this pipe and exchanging for the other catalyst. Hopefully it will be correct.

Konrad

PS. I went to Sidcup Toyota to get some bolts for the exhaust, and nobody attended the parts counter after I rang the bell. Waited 5 minutes and then went a nut and bolt specialist, who supplied me with stainless steel bolts and washers. Need I say more!!!!!

[t-spiritpete]

Hope all goes ok for you Konrad.

Pete.

[Konrad C]

Hope all goes ok for you Konrad.

Pete.

Thanks Pete.

Weather permitting, the job should be done next week.

I have just caught up with the changes exhaust industry. That's what I get for having a car too long.

[Harry Carri]

Hi Konrad,

I had a look in my folder and found a print out Simon the service receptionist did to show me the parts needed for my exhaust system to pass MOT. I don't know who the manufacturer was, I will try and find out.

700079 down pipe

099863 CAT converter

228625 middle silencer

25024 clamp-exhaust

251001 spring-exhaust pipe

255414 rubber buffer-silencer

255415 rubber buffer-silencer

On the diagram there is a - between digit 3 & 4 so 228-625 is listed next to middle silencer.

There are a different set of part numbers above the ones I listed, these are:

17410-02340 down pipe

17460-02090 CAT

17430-02218430-02200 , the 8 may be a 6 the print quality is not great.

Any help to you ?

Will see if I can get any manufacturer details and definite part numbers.

[Konrad C]

Hi Konrad,

I had a look in my folder and found a print out Simon the service receptionist did to show me the parts needed for my exhaust system to pass MOT. I don't know who the manufacturer was, I will try and find out.

700079 down pipe

099863 CAT converter

228625 middle silencer

25024 clamp-exhaust

251001 spring-exhaust pipe

255414 rubber buffer-silencer

255415 rubber buffer-silencer

On the diagram there is a - between digit 3 & 4 so 228-625 is listed next to middle silencer.

There are a different set of part numbers above the ones I listed, these are:

17410-02340 down pipe

17460-02090 CAT

17430-02218430-02200 , the 8 may be a 6 the print quality is not great.

Any help to you ?

Will see if I can get any manufacturer details and definite part numbers.

Thanks Matthew.

I was replying to you through PM when you posted this.

What I will do is get the catalytic converter and do the fitting. Only have to try.

Konrad

[Harry Carri]

Have replied to pm, Konrad.

The short answer after a bit of searching is this. The 099-863 seems to be a Bosal product and prices vary massively.

[Konrad C]

I have now fitted the system (in between the heavy showers). The system fitted well, but I need to check the cat to centre/rear joint because it it blowing by. //t he whole system is new, but I had rear of the car up the ramps instead of the front. This made fitting the cat section slightly harder. I did spray the spray the manifold to front downpipe bolts and thread with WD40, and left over night. The released without any problems. :D

I removed the old exhaust complete front to rear because of the fossilized bolts and joints.

Once I undone the manifold to downpipe bolts, only the supports to the body needed to be unbolted - only 7 bolts. I transferred the 3 rubber mounts from the old exhaust to the new.

The only other issue I had with the new system is that the thread cap on the cat pipe (for a redundant sensor) was loose and blowing by. A bit of gasket sealant and tightening sorted that.

Regarding the original exhaust, it was made by Walker for Toyota.

Apart from the slight blow by at one of the joints, the car sounds a little sporty, but not loud.

The exhaust for the 7A-FE is easy and at a cost of £140 not too expensive.

[waqar_lionheart]

Well done Konrad, Very thorough as usual. Sterling effort.

Regards,

Waqar

[Konrad C]

Tomorrow morning my car will have it's MOT test. I hope the new catalytic converter performs as good as my old one. I would have only changed the rear exhaust only if the flange of the catalytic converter had not corroded.

I had to replace the bolts on my new exhaust because the system was not sealing properly - http://www.toyotaownersclub.com/forums/topic/112330-water-dripping-from-under-car-just-after-new-exhaust-installed/

When I tried to undo the nuts and bolts on the join, one could turn to a certain point the stop! No certain amount of force was moving that nut past that point. The other nut and bolt were totally welded. It is as if the bolts had expanded locking the threads. The whole lot are supposed to be made of stainless steel.

The replacements were given to me by a friend who works in Kwik-fit. He say that is the only bolts they use.

The system is now sealed and with no obvious leaks. The back box is a bit boomy, but not as bad as before. Time will tell.

I will update on the MOT result.

[Konrad C]

The car past, but only after a while!!! The CO emissions were high then, it dropped down to 0.002. My mechanic say that my car needs time to warm up and the tester and other mechanics think the O2 sensor may be a bit lazy. I have had the odd EML a couple of week ago, but not recently. They don't think it is the catalytic converter and they think it has not burnt in properly. They suggested a full diagnostic or data logging.

The exhaust noise is becoming quieter with a resonating rasp.

I have been down the dual carriage way and the car is nice and smooth. The car seems as quiet as before - last week it was loud at slower speeds until I re-adjusted the exhaust.

I have been in contact with Bluetoy via PM about his issue and he changed the vacuum switch. This controls the butterfly valves to 4 of the 8 inlet valves.

From what Bluetoy has said mine may need changing too. There is a slightly younger version of my car at the breakers yard. I wonder if I should go and get those bits I need? I did get a the replacement brake caliper carrier from that car. I replaced warped front discs.

Anyway now the car has the certificate.

Will I keep the car by this time next year or replace it? time will tell.

[Konrad C]

Update. I recommend the front downpipe and the catalytic converter from Euro Car Parts, but would source the rear exhaust from elsewhere, as long it is a good brand. The first Klarius rear system I bought had a resonator failure. It got louder and is noticable from 2000 rpm onwards. Also it was louder with medium - large throttle opens at any revs, and also from cold starts.

There was also a course vibration which was worse in the 2200 - 2800 range, where the resonance was at it's worse. The second exhaust is so far a lot better.

Because I had to swap the exhaust. I put my old rear system on, and apart from the blow which forced the replacement, the car was very smooth and quiet!

If I could find somebody to remove a small section of corroded pipe and weld with stainless steel joint, I would gladly put it back.

Matthew, has you exhaust performed the same noise and vibration wise as the original?

[Harry Carri]

HI Konrad,

When I bought my Avensis it had a slightly fruity exhaust note. The seller had a weld done on the exhaust when preparing the car for the fresh MOT it was sold with. That slight blow very gradually worsened over two years and this year like yourself my old system was finished at the joints and was replaced.

The worn system didn't seem to vibrate, the only give away was the exhaust note.

Now for the first time I drive an Avensis with a mostly new system (back box remains from old system, unsure of the age of that section) and the noise level is lower.

Driving wise no discernanble difference possibly a little smoother but maybe that is just psychological.

Economy up straight away from a typical 38mpg to 44mpg so a 10% improvement. That was a great and welcome surprise.

[Konrad C]

Hi Matthew again.

Just finished setting up a new touch screen laptop.

From what you have said, the the front down pipe, and the catalytic converter which seam to be made of mild steel had to go. Only the rear has survived because it is made of mostly of stainless steel, apart from a small section from the joint to the first silencer, which also mild steel. This is where mine was blowing.

I have to say that I am much happier with the replacement exhaust. It has a slightly fruity sound but muted compared to the previous replacement. The harshness that was present before gone - 60 to 67 was torture before. The exhaust can only get more quiet as it carbons up - that will take time.

I am glad I did the work yesterday as the weather today was colder and wet.

Your fuel economy is great Matthew. Mine is good but Kent/SE London traffic does not help.

[Konrad C]

Update!

Replaced the catalytic converter and complete tail pipe due to the car not meeting the emissions and the noise of the back box. This replaced the Euro Car Parts React/Klarius system I got last year.

I went to my local car spares place and got Euroflo type approved catalytic converter and tail pipe for £111. The quality of Euroflo system is far better than the React/Klarius in a number of ways.

• The price was slightly cheaper
• The actual exhaust looks more like the original system
• The car is far quieter
• The cat' is type approved
• The fit is far better

The only minus is the cat' mount was welded above instead below, bring it close to the subframe. The end of the mount is pointing at an angle, which means it is nearly touching the underside of the car. This can be adjusted so no problem.

Comparing the rear silencers I have all three,

first the original

next the Klarius

lastly the Euroflo

Notice that the shape of the Klarius is different to the others. The flat sides does nothing to reduce resonance and actually amplifies the sound. The shape meant is fouling the under body shield, creating more noise.

I may add more in another post, but basically I am happy with the Euroflo system which I got from ABM in Plumstead.

This is the second major part I bought from them to replace poor goods from Euro Cat Parts. I say this for the benefit of other Avensis Mk1 owners who need to replace their exhaust. The part was the front brake disc and pads.

Just say I am the test subject. Car is smooth quiet.

Konrad

[fastbob72]

Excellent running post Konrad,ever considered a slot on Watchdog lol. I have to agree with you about Euro Car Parts though. They tend to be cheaper than everywhere else but there seems to be a reason for this I've bought a new exhaust system,all round discs and pads, drivebelt and several other bits and pieces from them.

The exhaust was a nightmare. On the vvti it is basically a one piece that fits around about where the gear lever is there are two mountings for exhaust rubbers either side of the rear silencer. It didn't matter how I did it it was impossible for the two rear mountings to bolted up properly and for the system to line up at the front. When I tried to tighten the front up properly it pushed the system upwards till it was hard against the undersise of the car If I bolted it first at the front then only one of the rear mounting points lined up right so eventually I had to loosely fit all three and tighten them up a bit at a time meaning all three mounting points were out of line but not enough so it fouled the floor. At first it caused vibration and resonance that settled down over time but even 8-9 months on I need to keep a peroidic check on the rear box as the bolts for the rear hangers work themselves loose at times.... there must be some torsional effect because it's not truly lined up thats causes this to happen.

Same with my brakes, don't get me wrong they work well and have never given me any cause for concern where safety is comcerned but there has always been a slight rubbing between the discs and pads that I have been unable to eradicate and believe me I have tried and tried and tried. There's like a high point or a slight warp on the discs because I have turned them by hand countless times and can observe the slight wobble by watching where the disc meets the caliper. The drivebelt is a little looser than i would like but seeing as I bought one for an Avensis without A/C because I removed the A/C system completely from mine I am unable to say if a direct replacement would have been any better. The air filter panel I bought from them I am 100% happy with though lol

Sent from my SM-N910F using Tapatalk

[Konrad C]

Excellent running post Konrad,ever considered a slot on Watchdog lol. I have to agree with you about Euro Car Parts though. They tend to be cheaper than everywhere else but there seems to be a reason for this I've bought a new exhaust system,all round discs and pads, drivebelt and several other bits and pieces from them.

The exhaust was a nightmare. On the vvti it is basically a one piece that fits around about where the gear lever is there are two mountings for exhaust rubbers either side of the rear silencer. It didn't matter how I did it it was impossible for the two rear mountings to bolted up properly and for the system to line up at the front. When I tried to tighten the front up properly it pushed the system upwards till it was hard against the undersise of the car If I bolted it first at the front then only one of the rear mounting points lined up right so eventually I had to loosely fit all three and tighten them up a bit at a time meaning all three mounting points were out of line but not enough so it fouled the floor. At first it caused vibration and resonance that settled down over time but even 8-9 months on I need to keep a peroidic check on the rear box as the bolts for the rear hangers work themselves loose at times.... there must be some torsional effect because it's not truly lined up thats causes this to happen.

Same with my brakes, don't get me wrong they work well and have never given me any cause for concern where safety is comcerned but there has always been a slight rubbing between the discs and pads that I have been unable to eradicate and believe me I have tried and tried and tried. There's like a high point or a slight warp on the discs because I have turned them by hand countless times and can observe the slight wobble by watching where the disc meets the caliper. The drivebelt is a little looser than i would like but seeing as I bought one for an Avensis without A/C because I removed the A/C system completely from mine I am unable to say if a direct replacement would have been any better. The air filter panel I bought from them I am 100% happy with though lol

Sent from my SM-N910F using Tapatalk

Thanks Bob. I like to try and detail my experience, and reading motoring magazines has influenced the way I post.

regarding the exhaust from Euro Car Parts, the Klarius rear silencer was the wrong shape, as it was close to touching the shield, especially when hot after a high speed journey. It was a touch louder that the Euroflo at all revs loads. it is interesting that the 10mm bolts on your exhaust work loose on the rear, as mine are tight. You did say the fitting may be pulling on them.

The filters I buy from Euro car Parts are good and they do sell Bosch options which I get for the oil filter. I always order on online, using the discount code then collect from store. When I bought spare drive belts, I bought Conti and if you go to the Continental website, they list the correct size for every car, plus the bypass version if the air-con is not available or not working.

My next project is to solder the possible dry joints on the Sony stereo power/speaker sockets.

I would love a job in Watchdog testing things.

[Alex-avensis]

Thanks very much Konrad it was  because of this post that I sourced a Euroflo exhaust backbox for my car. Must say I am very happy with it, if it lasts more than 2 years I`ll be happier still :)