Vauxhall Zafira A 1.8 16v Auto 2001 - P0170 Fault

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Sat 25 Jun 2016 14:08
Vauxhall Zafira A 1.8 16v Auto 2001 - P0170 Fault - Monster1973

Hi all,

I only purchased this Zafira last week and after putting it through an MOT it passed with flying colours. A £600 bargin...so far... When it was MOT the garage that did it did an error code check for me (I've used them for years and they are great!) There was no engine managment light on but when connected to te code reader the P0170 code came up. I have read a number of the chats on here in relation to the P0170 error code. All emission readings were passes and the Lambda reading was 1.03 with the HC at 4PPM although there is a slight hesitation at idle. Having looked at the rear silencer it does look quite rusty and worn so a replacement is on it's way. As is a fresh air filter.

What confuses me is why the engine management light is not on if there is an error code?

I am hoping that once the exhaust and filter are changed and it has had a good run on the motorway with some premium unleaded it may solve the problem.

I have noted that others on here have had similar problems and cleaned the throttle body to solve it, is that an easy enough job? Are there any links on here that show a step by step process.

Cheers

Ian

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Sat 25 Jun 2016 18:43
Vauxhall Zafira A 1.8 16v Auto 2001 - P0170 Fault - elekie&a/c doctor

So, does the mil light come on when the ignition is first switched on without engine running??

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Sun 26 Jun 2016 21:23
Vauxhall Zafira A 1.8 16v Auto 2001 - P0170 Fault - Monster1973

Every other symbol lights up plus the mileage. So no idea why the EM light does not??

Thanks for your reply.

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Sat 25 Jun 2016 19:17
Vauxhall Zafira A 1.8 16v Auto 2001 - P0170 Fault - TedCrilly

"What confuses me is why the engine management light is not on if there is an error code?

The code tells you a fault condition has happened, the light tells you a fault condition is happening. The code could have been stored from an event that happened years ago.

P0170 doesnt indicate a specific component is at fault, it indicates a fuel trim problem which in turn could be caused by one or many seperate and unrelated issues and it can be a difficult one to diagnose

Saying that its usually MAF, lambda or EGR related as these are the parts most likely to fail, but air/vacuum leaks and cracks in manifolds/heads can flag it up, even driving in torrential rain has been known to upset the mixture enough to flash the light.

Personaly I would get a £10 code reader off ebay and erase it in the hope it doesnt come back. If it does I suggest your best option is to find someone with the kit to run live data analysis and examine components dynamically. Otherwise you may find yourself guessing and throwing money at parts that might not need to be replaced.

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Sun 26 Jun 2016 21:37
Vauxhall Zafira A 1.8 16v Auto 2001 - P0170 Fault - Monster1973

Looking at the previous history the it had the MAF sensor replaced at 94k in 2012, it now has 109k on it having only done around 3k per year with the FSH.

I brought it 'blind' from eBay having done just the basic vehicle check and look over when I went to pick it up. It was is Peterborough and I am based in Birmingham. I gave it plenty of welly as well as the standard keeping it at 60mph for a good 40 miles on the M6. The auto box pulls really well and the engine is smooth with the exception of the idle hesitation when warmed up.

I certainly don't want to throw excessive cash at it, I only brought it because my Renault Epsace became beyond reasonable repair and I know that Zafiras are plentiful and easy to work on. I got the rear exhaust and fititng kit for less than £40 of eBay and I will fit that myself. My only concern is that it may get worse if I don't track it, after all that could be the reason the seller dropped it??

I'll have a look at code readers. Thanks for your response.

Ian

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Sun 26 Jun 2016 21:39
Vauxhall Zafira A 1.8 16v Auto 2001 - P0170 Fault - elekie&a/c doctor
I would suspect the eml light has been "disabled ".I think it is an led on these ,so either broken off the circuit board or blanked out.
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Sun 26 Jun 2016 21:45
Vauxhall Zafira A 1.8 16v Auto 2001 - P0170 Fault - Monster1973

Thanks for reply. Probably 'disabled' rather than broken lol.

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Sun 26 Jun 2016 22:04
Vauxhall Zafira A 1.8 16v Auto 2001 - P0170 Fault - Monster1973

To add;

I must say how impressed I was by how smooth it was when I drove it home from Peterborough. It was not an idea purchase but needed a 7 seater asap.

With the exception of the idle hesitation, which I thought when I collected the car was propbably due to the rear silencer as it sounded a little 'blowy', the car ticks over nicely once above idle rpm (currently at 820rpm from MOT test). Even the MOT guy said that it was a decent buy. It has only covered 50k in the past 10 years. I suspect that since its previous owner had it in 2011 at 94k it has only done around town, short hop school runs. Like I say it has done around 3k a year since 2011.

Are there any other known regular issues with these Zafiras?

I think these forums are brilliant, my other car is a 2000 reg Rover 75 2L Auto Conni SE and the information on the 75/ZT forum has always saved me £££s!

Thanks once again!

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Sun 26 Jun 2016 22:40
Vauxhall Zafira A 1.8 16v Auto 2001 - P0170 Fault - elekie&a/c doctor

The Zafira A is a really good all-rounder for not a lot of cash.Very few issues other than what you have experienced.Keep an eye on oil level,as these engines are known high users.Interestingly ,the later "B" model from around 2005 can be total money pits and not as reliable.

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