High emissions on my R33 skyline!

[Rb25]

Well lads. I bought a R33 Skyline 2.5turbo there about a month ago but havin problems getin it Nct'd cause of high emissions. The car is standard with cat back exhaust, frount mount intercooler, and mushroom air filter.
I put it true nct 3 times and it failed.

First time Emissions
Low idle CO 6.73 vol% (above 0.50% fail)
High idle CO 6.18 vol% (above 0.30% fail)
Lambda: 0.83 (not between 0.97 and 1.03 fail)
HC 198ppm

I then changed the cat, changed the lambda sensor with another second hand one, and mixed dipetane with fuel and gave it a good drive!!!

Second Nct time Emissions where:
Low idle CO 4.39 vol% (above 0.50% fail)
High idle CO 2.97 vol% (above 0.30% fail)
Lambda: 0.91 (not between 0.97 and 1.03 fail)
HC 205ppm (above 200ppm fail)

I then replaced the lambda sensor with a new universal one!!!

Third Nct time Emissions where:
Low idle CO 3.21 vol% (above 0.50% fail)
High idle CO 4.71 vol% (above 0.30% fail)
Lambda: 0.86 (not between 0.97 and 1.03 fail)
HC 223ppm (above 200ppm fail)

The nct man said the lambda sensor reading was constatly going up and down .

So anyone any idea what could be causing these high emissions? Could the ecu be f**ked?????

[pepsterx]

Check all gaskets from the head to the back of the exhaust, intake system leaks vacuum or boost ! What part of the country are you in ?

[Deco84]

Which nct centre was it there machines are all out of whack tell them ya want it retested on the lane u got the best reading on . Happened me and I made them retest it and it passed on a different lane . My problem was to do with imbalance in coilivers but I'm sure if one machine is off they all are

[celicacrasher]

maybe you sould check your engine timing

[Rb25]

Check all gaskets from the head to the back of the exhaust, intake system leaks vacuum or boost ! What part of the country are you in ?

Im from mayo lad!!!

[Rb25]

Which nct centre was it there machines are all out of whack tell them ya want it retested on the lane u got the best reading on . Happened me and I made them retest it and it passed on a different lane . My problem was to do with imbalance in coilivers but I'm sure if one machine is off they all are

It was Ballina Nct centre in Mayo! Theres only one lane there lad!!!!

[Deco84]

ah right there goes my theory lol good luck findin the problem man

[Sir Diffsalot]

Could it be the afm? Could ya borrow a known good one of someone

[nicky h]

my friend had the same problem i gave him a lend of a rb20det lambda and passed,
id get a genuine lambda if you could

[paulr5]

OP Simple, your first results say it all and every result after that says it's running WAY too rich, it's either stuck in closed loop mode wich means the ecu is stuck in "cold start" mode adding loads of fuel, fix is to try clean the sensor (long shot) or change the coolant temp sensor. afik the rb sensor is yellow and can't be swapped with a sr one (blue) but I'm not sure.
Or
Your piping to / fuel pressure regulator is dodgy the small vacuume pipe that goes to the manifold might have a hole in it or some tard T'd into it causing it not to work.

[shaneS14]

your car is over fueling man , your maf could be fucked, bad injector, wrong fuel pressure ect

[pepsterx]

I'm just outside of claremorris give me a shout tomorrow at some stage if it suits you, 0879551206 or you can try and fix it with internet advice !! I'm arround all day