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Dirty Air filter / Vehicle Inspection failure

778 views 9 replies 4 participants last post by  sbaert 
#1 ·
Just came back from vehicle inspecion.

The test failed because of this:
CO% 5.61 (Carbon Monoxide) too high. / Rich Fuel condition.

Everything else passed.

I did this test with a dirty air filter, its actually ripped on one side.

Hopefully this was the only reason.

Or maybe some SENSORS are defective.
 
#3 ·
^This. And always do full tune up (oil change, all filters, ignition, etc.) before going for a emissions test. And most importantly, drive the crap out of the car on the way to the test station and then leave it running while you wait.

This is one instance where you want the engine to be as hot as you can.

Hotter engine = fewer unburnt gasses
 
#4 ·
Air filter condition is unrelated. If it had a tear it's getting more free flowing air...

Do a tune up on any elements that are old - fresh plugs, rotor, cap, inspect wires...
Injectors, mixture
 
#5 ·
So the LAMBDA SENSOR is a likely suspect which I will replace.

Original 139.89 Euros at MbSpecialist.com

My EHPA (Electo Hydraulic Actuator) is second hand & appears to be faulty (only had it for 5 months).

Could that also affect the air/fuel mixture & high Carbon Monoxide readings?

24/03/2016 Reading: CO% 0,37
24/03/2017 Reading: CO% 5,61

How is that possible to suddenly after 1 year shoot up so HIGH?
 
#7 ·
My EHPA (Electo Hydraulic Actuator) is second hand & appears to be faulty (only had it for 5 months).

Could that also affect the air/fuel mixture & high Carbon Monoxide readings?

24/03/2016 Reading: CO% 0,37
24/03/2017 Reading: CO% 5,61

How is that possible to suddenly after 1 year shoot up so HIGH?
A brand new Bosch EHA specifically for your M103 is the only real fix.
 
#8 ·
Changed the plugs and looks like this is causing the high CO2 carbon monoxide emissions test result.

Bad oil rings. (By the looks of these plugs).
In order from left to right 1 3 4 2 (so number 4 looks the worst with most carbon deposits).

I cant afford for a mechanic to do this job (1500 euros) to change the oil rings.
And I dont have to resources or time to do it myself.
And I am running out of time - only have until 24 April 2017 for the final emissions test.

But putting in the new BOSCH Oxygen sensor made a huge difference.
And apparently the second hand EHA is ok.

Too bad that these oil rings are gone.
Time to get another car it seems.

Unless there is a trick to pass the emissions inspection.
I have changed the oil, new distributor cap + rotor, new plug wires, new NGK BP6EFS spark plugs, new air filter.

Injectors + mixture still not done.
 

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#9 ·
Its more likely valve stem seals, not piston rings depending on your mileage and whether the head has ever been refreshed or not.

If time is really not in your favor, get your fuel tank down to ~1/4 and go dump a gallon of denatured alcohol in the tank and you should pass once the mixture is set correctly. Drive the car HARD for about 20minutes and drive immediately to the emissions station. Do not turn the car off and let it heat soak. Drive right in and have it tested immediately.
 
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