Catalytic converter fault

tug · Post by **tug** » Sat Jan 11, 2020 8:43 am

Glad you got it sorted jock, can i ask how much to have the valve stem seals replaced cos i think mine are not 100%

If i leave mine idling for a long while, say 20 mins and pull off, i get some blue smoke which clears almost immediately and then goes back to normal. Have been told not to worry about it by my local indie its relatively normal for age and mileage of the zed. But i would like to have it sorted if i can afford it.

Also, recalibrated? what did they do mate? just interested in what that does to the overall running and performance.

Cheers, tug

jock156 · Post by **jock156** » Sat Jan 11, 2020 11:10 am

I don't know what they done but will ask when I collect it.

Please se the following for your BMW Z4 Valve Stem Seal replacement.

Labour - £750
- Removal of Rocker & Timing Chain / Cams & Rockers - Installation of Valve stem seals x16, install new timing chain & tensioner recommenced inc new rocker gasket, clean Vanos units and test.

Parts
- Timing Chain Kit FULL £255
- Elring Rocker Cover Gasket £50
- Valve steam seal x16 £45

TOTAL: £1100

Recommend Oil & Filter Change
Motul Oil & Mahle Filter
£165 extra

Tanel · Post by **Tanel** » Sat Jan 11, 2020 11:25 am

I have a 3.0si and there is a rattling noise coming from the exhaust. When under the car you can hear it around headers, where the cats are. Is it possible that one of the cats has come loose?

tug · Post by **tug** » Sat Jan 11, 2020 3:21 pm

WOW! thats some work done there mate!

Think i will just "not worry" bout mine its a lot cheaper that way.

Tanel wrote: ↑Sat Jan 11, 2020 11:25 am I have a 3.0si and there is a rattling noise coming from the exhaust. When under the car you can hear it around headers, where the cats are. Is it possible that one of the cats has come loose?

I would first off get the zed up on the ramp & have a good look at the cat "containers" to see if any cracks have appeared. There was a rattle on mine also. But after the TIG weld all was well again. Hope its as simple as that for you mate.

Cheers, tug

ph001 · Post by **ph001** » Sat Jan 11, 2020 3:48 pm

I think it’s virtually unheard of for the 6 pots to suffer cracked manifolds, more likely one of the exhaust bracket suspension rubbers is split / missing. You will need to get under the car or get it up on ramps to check.

rajen44 · Post by **rajen44** » Fri Aug 21, 2020 9:18 pm

Hi guys,

I gotta resurrect this again, sorry.

I've got a 2.0 about 80k on the clock and the same code tug had cropped up. Very rarely I get the grey/blue smoke when it's idle. I've been told I dont have a crack on my manifold but maybe the cat needs replacing? I did use the can to put into my fuel tank. Im losing a bit of oil from time to time due to head gasket not being fitted in properly so that needs looking at. Could I get away with doing what Tug mentioned, smashing it into 4000 revs or am I looking at replacing the cat converter? I'm a bit lost at the minute as to what the right answer is and whether to try and get an MOT done to see how the emission is etc.

Look forward to hearing from you guys.

Thanks.

tug · Post by **tug** » Sat Aug 22, 2020 7:11 am

Hi rajen, unless you are really unlucky the cats will be fine. I used to fear the worst when i first got my 2.0 & the pesky light kept coming on.

I have a really helpful BMW indie near me (he found the crack in the cat container by thorough inspection) While the light was on he tested the emissions for me (FOC

) they were perfectly fine and would pass the strict MOT easily.

There is a trick on the 2.0 where the throttle can be reset.

Turn ignition on (all dash lights on, engine off) count to 15.

Turn ignition off, count to 15 then start engine.

This will wipe the adaptations the ecu has made according to your and previous owners driving styles. Now you should get on the nearest motorway and open the zed up taking it up to at least 4000 revs in each gear not 6th unless you can get away with it (it will be doing over 100mph

)

Then whenever possible, always (only when engine is warmed up) run the car in this style. I have been driving mine like this for a few years now & the engine is smooth as silk & no pesky emission light for as long as i can remember.

Cheers, tug

Z4paul · Post by **Z4paul** » Sat Aug 22, 2020 8:03 am

tug wrote: ↑Sat Aug 22, 2020 7:11 am Hi rajen, unless you are really unlucky the cats will be fine. I used to fear the worst when i first got my 2.0 & the pesky light kept coming on.

I have a really helpful BMW indie near me (he found the crack in the cat container by thorough inspection) While the light was on he tested the emissions for me (FOC ) they were perfectly fine and would pass the strict MOT easily.

There is a trick on the 2.0 where the throttle can be reset.

Turn ignition on (all dash lights on, engine off) count to 15.

Turn ignition off, count to 15 then start engine.

This will wipe the adaptations the ecu has made according to your and previous owners driving styles. Now you should get on the nearest motorway and open the zed up taking it up to at least 4000 revs in each gear not 6th unless you can get away with it (it will be doing over 100mph )

Then whenever possible, always (only when engine is warmed up) run the car in this style. I have been driving mine like this for a few years now & the engine is smooth as silk & no pesky emission light for as long as i can remember.

Cheers, tug

Some really helpful suggestions Tug, thanks for these. Just a few months into e85 2.0 ownership and i think these are fantastic cars but owners need to not jump to the worst case scenario i think. Read a number of times about the 'need for speed' or revs at least! My light has come on a couple of times but only when in town traffic - i have adjusted my driving style, when able, and used cataclean once - clear since then. Not read about the throttle re set before - did you notice a difference or is the goal of that to reduce EML coming on? Cheers, paul

tug · Post by **tug** » Sat Aug 22, 2020 8:37 am

Hi Paul, yes you do notice a difference. When i first got my zed i thought it was quite sluggish for an aspirated sports engine, but knowing the previous owner was a woman living in a city centre i thought that it probably needs a good run out, not just to the supermarket

After a while it got no better and the emissions light kept appearing. So after a lot of reading and asking questions i found the throttle reset procedure. After doing this the zed was like a different car. The engine seemed to be a lot more responsive and revving a lot better and didn't feel like it was being held back.

Although the pesky light kept coming on, the zed was a lot better. Like a lot of new owners i didn't want to thrash it too much in case it hurt it

But after 6 years ownership and minimal trouble i found that the N46 needs to be thrashed regularly to "keep it clear" so to speak. Like i posted before, i drive my zed "like i Stole it"

whenever i can and never have problems with the pesky light.

Cheers, tug

Z4paul · Post by **Z4paul** » Sat Aug 22, 2020 9:18 am

Fantastic, i will try this and see if i get a similar outcome.
Thanks again, paul

Jfgoldfish · Post by **Jfgoldfish** » Sat Aug 22, 2020 7:58 pm

tug wrote: ↑Sat Jan 11, 2020 8:43 am Glad you got it sorted jock, can i ask how much to have the valve stem seals replaced cos i think mine are not 100%

Just thought I would mention; there is a place in Nuneaton that will do valve stem seals for £390 flat rate. Many garages charge twice that, it is a job worth doing on these 2 litre engines.

Z4-forum.com

Z4-forum.com