Technical Tips to reduce emissions

[madbilly]

Hello everyone,

My 2005 1.4 8V Dynamic Grande Punto only just passed its emissions test. This was on a retest, so I did the obvious things like replacing the spark plugs (old ones were oily!), changing the oil and filter (old oil was black) and air filter (dirty but not terrible). I also found that one of the breather hoses (from the back of the engine, I presume the crankcase breather) was disconnected so I reconnected that (top of the engine around the throttle was very oily, I presume from this).

Despite all this the technician had to rev the engine hard for about 10 minutes to get the emissions to get below the required amount.

So, I expect that it will fail again next time if I don't do something to fix it. Any suggestions?

• Engine "cleaner" that I put in the fuel tank - does anyone have any experience of this actually working, or is it just a placebo to use alongside other measures?
• Cleaning out the oil breather tubes from the cam cover and the crankcase - if they're blocked, will this improve emissions?
• Replacing the catalytic converter? A pretty expensive option that might not be the cause!
• Driving in 3rd gear at the speed limit on the motorway for one junction on the motorway and getting to the testing station as quickly as possible so the engine is still super-hot for the emissions test?!

Note I have no warning lights for sensors like the intake temperature or MAF, but would these show?


Any other suggestions?

Cheers

 

[Rado77]

Worse thing of all is oil on spark plugs, that's big problem. While PCV hose was connected back, run car 1 month and then check new spark plugs again. They must be dry and colored like white coffee

Strange that all 4 spark plugs were oily. I can imagine 1 spark plug oily because of issue on 1 cylinder...but all 4? Are you sure that it was oil and not fuel? I believe it was fuel because car is running and passed emissions too

 

[nikrox]

As said..are you sure its oil and not petrol?..leave the plugs out and wait to see if they dry out ..petrol evaporates.

How is the general day to day running?..is it used for mainly short trips?

New plugs,check correct grade against a reliable source,gap and maybe consider a bottle of Cat clean or similar in the tank.

You 'could' consider replacing the ht leads and coil pack 'if' they are original ..that is if its not running ok..

You have a year to sort it..so dont rush into things..

 

[AndyRKett]

Your profile says you’re in France, do you live in a city and spend all day stuck in traffic (the fun of Paris traffic springs to mind) or are you out in the country? Lots of idling and sort trips can cause the engine to produce and get clogged on soot.

Also you mention the condition of the oil and air filter, has the car had regular servicing or is that generally neglected as it will make a big difference

 

[torniojaws]

Had the same on mine. What "solved" it for me was to:

1. When you have about 1/4 tank left
2. Add 10 liters of E85 (ethanol fuel)
3. Then, just before the inspection, drive around for about 20 minutes at 3000+ rpm most of the time (or about 10 km on a highway on 3rd gear)
4. When you pass with zero(!) emissions, fill the car completely with normal fuel and try to drive it empty as soon as possible, and fill it again with normal fuel

While it's not a Flex-Fuel engine (afaik?), this little amount will do no harm, unless you leave it there for a long time. I've heard it might damage the fuel injectors and/or fuel lines.

The real issue is very likely either the catalytic converter or the muffler. On mine, I noticed after passing the inspection that there's basically a hole in my muffler But I also did clean my catalytic converter/manifold in washing machine detergent water (about 2 dl of detergent + water to cover the manifold fully), so will be interesting to see what happens in the next inspection in March 2020.

 

[madbilly]

Hi all!
Please excuse the delay, been busy. Thanks for all the suggestions.

I'm not sure it's oil, it just looked black and oily, but maybe it was petrol with soot underneath. However, I didn't smell petrol when I removed them. Most of each plug was like white coffee, just the insulator was black. I replaced them, so I will check if the old ones have dried out and in a few weeks I'll check the ones that are in to see what state they're in.

Daily running is fine, but yes it it mainly used for short trips, rarely run for more than 10 minutes at a time, barely enough time to get warmed up. the trips do get up to 80 km/h though as I'm not in a city. It does a ~1 hour trip every month or so on the motorway so it does get cooked every now and then (130 mk/h means high revs and the summers here are HOT!).


The HT leads and coil pack are not original, I changed them myself a few years ago.

Servicing of plugs and air filter is probably inline with the amount of mileage it does, but I probably should have changed the oil more frequently.

Plug gaps I do check and the new ones I put in were correct, as were the ones I took out. The oil is correct, it's 5W40 fully synthetic and I checked the spec when I first got the car 6 years ago and have used the same brand ever since.

Cat clean... does it actually do anything? Or is it just feel good factor? How is it supposed to work?
torniojaws - thanks for the suggestion! I checked the nearest location for E85 I was very surprised to learn that it is not far away, 15-20 minutes drive, so that will be very convenient for this when I next need it! You're right though, it needs to be removed quickly as it can corrode rubber seals.

Using detergent to clean the catalyst and rear silencer will be absolute last resort!

And thankfully I've got 2 years until the next test as that's the French rules, unless I choose to sell it in which case it must have a valid test result less than 6 months old.


Cheers

 

[nikrox]

I guess catclean is a concentrated form of detergent(s)..I do know that its guaranteed to work,or your money back and have been told by my trusted mot garage that it works..
End of the day it's your choice. If its barleyonly just passing the emisions then its not running correct and £15's worth of catclean may help,both the car and environment.

 

[madbilly]

Ok it's worth a shot then, thanks