1.6hdi emissions fail

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blonogasoven
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Joined: 22 Oct 2021, 13:05

1.6hdi emissions fail

Post by blonogasoven »

Hi, this is my first post. I did search the forum for any posts that could help but the posts I found were relating to different issues.
I have a 2006 C4 with the 90bhp 1.6hdi engine. It's just past 90k. It has fsh until 72k and since then I've done it myself.
It had a bit of smoke at start up and needed an italian tune upmto pass emissions last year. I decided to change the glow plugs which was the worst idea I've ever had, snd I've had some bad ones. Two broke off. Since the car has always ran great I decided to go all in and take the head off. I have previously replaced lifters on a Berlingo that had a snapped cam belt so knew my way around the engine.
The injectors were dry as a bone, which was a huge problem as 2 of them just would not come out. I was in for a penny so bought a 2nd hand head. I checked it with a straight edge and it was level.
I put it all back together, including 2 replacement injectors, new cam belt and water pump (I'm pretty sure it had been done as the belt looked too new but changed them anyway). While it was apart I cleaned the intake and the egr.
It started but was smoky. White smoke on tickover and black smoke when I revved it. I changed all the injectors for known good (they passed the leak off test), I changed the maf (on advice when I was desperate) and I double checked the cam and pump timing. The turbo has no play, there was a few drips of oil in the intercooler, I changed oil, oil filter and air filter.
I put in some wynns gold and revved it hard before the MOT but it still couldn't pass. The best it got was 3.18 when it needs to be below 3.

There is no evidence that the head gasket is leaking, no water in the oil or under the cap and no oil or pressure in the header tank. There is a tiny bit of smoke at idle and quite a bit when I touch the throttle, hence why it failed.

I'm out of ideas. I realise that I'm taking a chance with 2nd hand parts but the car isn't worth spending loads on. The only thing it failed on was emissions so I just don't want to scrap it if it has a chance.

Sorry for the lengthy post but I wanted to give you as much info as possible.

Is there anything else I can do before I scrap it?

Thanks for reading
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bobins
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Re: 1.6hdi emissions fail

Post by bobins »

This is more to prompt anyone else who knows more - but do the injectors on these need to be coded in, or is it not really an issue on used injectors ?
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Paul-R
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Re: 1.6hdi emissions fail

Post by Paul-R »

Quite probably (almost certainly?) - our 2015 1.6 Blue HDi 308 needed coding in when I changed an injector a year ago.

Being second hand is irrelevant for this. Unless the injector has been reconditioned (you should get a new code for that) you should use the code that's printed on the injector as this is the closest you'll get to the correction factor that the engine ECU needs.
blonogasoven
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Joined: 22 Oct 2021, 13:05

Re: 1.6hdi emissions fail

Post by blonogasoven »

Hi, thanks for the replies. I have Diagbox and I have coded the injectors. I just don't know what else could be causing the smoke. It looks like it's toast, such a shame as it passed on everything else.
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bobins
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Re: 1.6hdi emissions fail

Post by bobins »

Was the MAF a genuine one or an el-cheapo eBay special ? There's plenty of dodgy MAF sensors out there !
blonogasoven
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Re: 1.6hdi emissions fail

Post by blonogasoven »

The maf was a genuine used good one. Would a bad maf cause the smoke?
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moizeau
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Re: 1.6hdi emissions fail

Post by moizeau »

My Dispatch smoked white until warmed up and stank of diesel, in my case it was the EGR. As you've got Diagbox you could do an actuator test to rule it out.
blonogasoven
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Joined: 22 Oct 2021, 13:05

Re: 1.6hdi emissions fail

Post by blonogasoven »

Thanks. The smoke is less when it's warm but still there, especially when I accelerate. When I rebuilt the engine I removed the egr and cleaned it.
blonogasoven
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Re: 1.6hdi emissions fail

Post by blonogasoven »

Forgot to add that I did test the actuator.
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Paul-R
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Re: 1.6hdi emissions fail

Post by Paul-R »

Going back to your first post, you said that you had had black smoke at certain times. You shouldn't get any black smoke out if it has a working particulate filter. Could the filter have been removed or disabled at some time?
blonogasoven
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Joined: 22 Oct 2021, 13:05

Re: 1.6hdi emissions fail

Post by blonogasoven »

When I rev it hard I get black smoke but under pretty much any acceleration I get white smoke, not thick but enough to fail emmissions. I was still driving it until it ran out of MOT. When it's driving normally I can't see any smoke at the back even when there's someone behind but when I push the throttle I see the smoke.
This is the 90bhp engine, I'm not sure it has a DPF but it had been maintained by Citroen up to 20k ago and I haven't disabled anything.
Thank you everyone for the replies, it's giving me more to check. I have enough room on the driveway that I can keep it to work on.
I was wondering if there was a 'you should have done this....' solution but I think it will be just checking everything again until I find the problem.
blonogasoven
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Re: 1.6hdi emissions fail

Post by blonogasoven »

It's the 9hx version
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Doo
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Re: 1.6hdi emissions fail

Post by Doo »

blonogasoven wrote:
22 Oct 2021, 13:31
Hi, this is my first post. I did search the forum for any posts that could help but the posts I found were relating to different issues.
I have a 2006 C4 with the 90bhp 1.6hdi engine. It's just past 90k. It has fsh until 72k and since then I've done it myself.
It had a bit of smoke at start up and needed an italian tune upmto pass emissions last year. I decided to change the glow plugs which was the worst idea I've ever had, snd I've had some bad ones. Two broke off. Since the car has always ran great I decided to go all in and take the head off. I have previously replaced lifters on a Berlingo that had a snapped cam belt so knew my way around the engine.
The injectors were dry as a bone, which was a huge problem as 2 of them just would not come out. I was in for a penny so bought a 2nd hand head. I checked it with a straight edge and it was level.
I put it all back together, including 2 replacement injectors, new cam belt and water pump (I'm pretty sure it had been done as the belt looked too new but changed them anyway). While it was apart I cleaned the intake and the egr.
It started but was smoky. White smoke on tickover and black smoke when I revved it. I changed all the injectors for known good (they passed the leak off test), I changed the maf (on advice when I was desperate) and I double checked the cam and pump timing. The turbo has no play, there was a few drips of oil in the intercooler, I changed oil, oil filter and air filter.
I put in some wynns gold and revved it hard before the MOT but it still couldn't pass. The best it got was 3.18 when it needs to be below 3.

There is no evidence that the head gasket is leaking, no water in the oil or under the cap and no oil or pressure in the header tank. There is a tiny bit of smoke at idle and quite a bit when I touch the throttle, hence why it failed.

I'm out of ideas. I realise that I'm taking a chance with 2nd hand parts but the car isn't worth spending loads on. The only thing it failed on was emissions so I just don't want to scrap it if it has a chance.

Sorry for the lengthy post but I wanted to give you as much info as possible.

Is there anything else I can do before I scrap it?

Thanks for reading
I imagine you will have put some good oil in it, but do you use supermarket diesel? There are the naysayers, but I only use BP Ultimate (or sometimes the Esso Synergy or Shell V Power diesels) as when wife first got her 2007 C4, it was running like a lump of custard. I suggested she try BP Ultimate and within a week the car was a different machine. No smoke, no hesitation, no furious acceleration "just" to pull away and no lumpy idle. She was delighted that I didn't have to take it for an Italian Tune Up every week and more so at the less fuel burned. Bonus being her last mot a couple of weeks ago showed 0.09 on the smoke test which was great. The tester exclaimed that's it was the first time he'd seen a Citroen with an original turbo :-D

The only other possibility is a clogged breather system situated on the plastic cam cover. You can get a replacement on the bay if you key in PEUGEOT CITROEN 1.6 HDI CRANKCASE BREATHER VALVE OIL SEPARATOR DIAPHRAGM.

It could be burning a wee drop of oil due to pressurisation, giving the white smoke. Also check all intercooler hoses are tight and no pin holes in the intercooler.
blonogasoven
Posts: 8
Joined: 22 Oct 2021, 13:05

Re: 1.6hdi emissions fail

Post by blonogasoven »

Thanks for the tips. I'll check the crankcase breather.