Failed MOT on emissions
 

Hi Guys, Looking for some more help please :rolleyes:
Volvo 2.0 Turbo, B200FT, red block engine, 1993, 217,000 miles.
Surprisingly failed the MOT today on emissions, CO value on fast idle was 0.67 compared to 0.18 last year, limit is 0.20%. MOT guy spotted a very very light misfire (which I had not noticed ) so I am going for the obvious,

4 new plugs ECP list 2 NGK options ???
air filter
oil and filter already changed this month
new lambda sensor ( I have one in stock )
check for vacuum leaks
refit exhaust, very slight blow on back box.

Any further tips on what to check/clean/replace will be gratefully received.
Thanks, Don.

Check leads if misfiring.

I would do the basics of plugs, leads, cap and rotor as a start.

Monitor the lambda sensor to see what it is doing before considering changing it

Leads rotor arm and dizzy cap were replaced a few years ago but I will check them and replace if necessary.

Hi, The readings on my 1998 V70 were up on last year and it failed ITV [ mot ]
A few people on here reco`d Forte advanced formula gas treatment. I threw a bottle into half a tank about a week before re-test and gave the car an Italian tune-up enroute to the test. Levels had dropped and it passed. Given the price of forte it may be worth a try; nothing to lose. jack

All items on your list including the new Lambda sensor, given the mileage (217k) there's a fair chance it's the culprit, they only have a service life of 100k miles or 10 years. Cats only last a similar lifetime but can often be recovered with Cataclean or similar (someone mentioned the Forte Advanced Gas Treatment, similar stuff, does similar things) and an Italian Decoke.

Before you start adding the new parts, pull fuse #1 out and leave it out while you add the new parts, replace afterwards before starting. This will erase the fault codes in the ECU memory giving it a "clean slate" to start with so the ECU can take advantage of the new Lambda, air filter, plugs etc and tune the engine for optimal emissions.

May also be worth checking that when the throttle is released, as it returns to idle position it oerates the idle switch in the Throttle Position Switch (TPS). This can be done easily by opening the throttle by hand (engine off) and slowly releasing it and listening for a click from the TPS as it returns to idle position.

Last thing, clean the MAF and make sure there aren't any blockages in it, sometimes with certain air filters there is a layer of foam that disintegrates and blocks the MAF - use carb cleaner or if you can find it, MAF cleaner, squirting it through both ways.

Good luck and keep us posted! ;) :D

Dave and Jack Thank you. I have ordered the forte stuff and am just about to order the plugs and filter from ECP ( Easter Sale ) the reviews for the forte seem all good even to the point of being solely responsible for a retest pass. The cat is fairly new so that should be ok, I have carb cleaner in stock so will clean the MAF when I replace the filter.

Good luck with it, don't forget to check the gap on the plugs before fitting (should be 0.65 -0.7mm) and set them if necessary, i'd definitely do the Lambda sensor unless you know it's been changed in the past 10 years as a failing Lambda gives a low output, indicating to the ECU the engine is running lean so the ECU enriches the mixture.

I had a Lambda sensor fail during the emissions test once, was fascinating watching the CO level start of normal then slowly creep up!
When it got to 9% the tester pulled the sample pipe out of the tailpipes though so i don't know how rich it would have got!

On the way home, the MIL light came on and i was able to read the code off the ECU when i stopped (non-Volvo, has a flashing LED for the code) and confirmed it was the front bank (V6) Lambda so i changed both, reset the ECU and hooned it back to the test station for the pass certificate.

He couldn't really refuse, it came up as 0.00% CO and something like 90ppm HC so was well within it's limits! :thumbs_up:

Quick question, BPR6ES OR BPR7ES ??

I have BPR6ES in mine