Vauxhall Astra G Coupe/Convertible (2000 - 2004) - 03 1.8 High emissions

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Fri 2 Oct 2009 18:47
03 1.8 High emissions - helpmyastra
Hi,

I would like your help! This is quite a long story so i will try to keep it short. 18 months ago my cars engine stared to idle very rougly ranging from500-1500 rpm. My local garage wasn't sure what the roblem was, they replaced the Lambda hoping to resolve the issue however the problem continued. So they then replaced the throttle body, the problem stil persisted only now the car wouldn't go above 70 (i mean 60.) It turned out to be the mass airflow meter which i replaced and purchased it for £30.00 from ebay. (The previous owner had ftted an after market air filter.)
My car emissions ar now running at 10% and the on board computer tells me that when i'm idleing i'm doing 0.3 gph (i think the norm is 0.2 when idle??) Anyway another local garage suggested i replace the CAT and a engine temperature guage which i did however the problem still exits. When on the way to Cornwall (a 5 hour drive) i pulled over and left the car running for 30 seconds when the eml came on. The error code is P0170 & P0420 Please correct me if i'm wrong but does the first code relate to the fuel mx and the second to the CAT??
So i'm now left with a rather large hole in my pocket and yet my car is still running rich.
What could be the problem given what i've replaced?

Your advice would be much appreciated.
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Fri 2 Oct 2009 22:09
03 1.8 High emissions - SpamCan61 {P}
As detailed in this thread:-

www.honestjohn.co.uk/forum/post/index.htm?t=58005

SWMBO's 1.8 Zafira (Z18engine) had fuel trim error ( P0170) and that was down to one of the lambda sensors.

I'd be a little suspicious of the eBay MAF, is it a pattern part or a pukka GM replacement? Same question with the replaced lambda sensor.

By the look of it I'd get an auto electrician / dealer to read live data and see what's going on.
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Fri 2 Oct 2009 22:41
03 1.8 High emissions - bell boy
ive had success with pattern mafs and saved a bundle
however i did have one out or parameters too
so
im sitting on the fence
ow
splinter
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Fri 2 Oct 2009 23:06
03 1.8 High emissions - SpamCan61 {P}
Chapter and verse on P0420 here:-

www.tegger.com/hondafaq/p0420.html

Which is probably relevant for your Astra
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Sat 3 Oct 2009 01:06
03 1.8 High emissions - helpmyastra
Interesting read thank you.

Question for you could an after market air filter break the ECU?
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Sat 3 Oct 2009 14:47
03 1.8 High emissions - SpamCan61 {P}
An oil filled aftermarket air filter could kill the MAF but I don't see it killing the ECU.

Whilst I'm a little suspicious of an aftermarket MAF bb's got way more experience than me so I'd put it low down on the suspect list. Can't really think of anything else without getting some live diagnostics done.
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Sat 3 Oct 2009 00:58
03 1.8 High emissions - helpmyastra
Hi the only question I would put to you on the back of that is. If the mass air flow meter was not the correct part then the side affects of that would surely be more than high emissions?
i.e. poor throttle response?
The lambda was from Vauxhall.

Thank you for helping me!
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