Evening all,

This is my first post here so please be gentle =P

I've recently brought an ST202 and today it went for its mot, apart from the various braking issues it failed on engine emissions. I know the car has been sat for a year or so and it did have some old fuel in it so I'm hoping that a fresh tank and some Wynns fuel treatment will do the job however the natural idle speed was lower than the limits, is there anything I can do to bump up the idle a fraction? Also is there anything else folk would suggest to get it through?

Emissions sheet attached FYI.

get a new CAT

Lambda/oxygensensor in exhaust might be out. New fuelfilter. New airfilter. New sparkplugs. Change oil and filter. Good luck.

Cheers for the suggestions, I'm also contemplating contacting Toyota in the morning to find out mm/yy build date as I believe if my car was before August 1995 then it can be tested to the more relaxed emissions (?), I will still be changing lambda sensor though, any recommendations on places to buy? I believe mine is the 2 bolt down type not the screw in one.

Air filter is a cone aftermarket and I was planning on changing other service items. I was hoping not to change the cat if it can be helped.

I'll keep you posted.

Amazon/eBay is far cheaper than any parts store. If you choose to do a parts store do advanced auto. There is always coupons online to get 20-30% off so its almost same price as eBay/amazon. Just make sure you don't use Bosch parts on your celica/imports it does not work the best. Every time.I go with Bosch I had issues.

Hi all,

Sorry this problem is still ongoing. I replaced the lambda, the car got retested and it passed the lambda test but still failed CO. Today I changed the cat and guess what, it's now failing again on both lambda and CO. I can't find any leaks on the system but I'm now looking at plugs and filter changes.

Original failure results as OP.

Post MoT with Denso lambda fast idle values: Lambda = 1.026, CO = 0.74%. Passes natural idle test.
Today's MoT with Denso lambda and pattern part new cat fast idle values: Lambda = 1.037, CO = 0.42%. Again passes natural idle.

Has anyone experienced issues with pattern part cats?

My only other thought is that the few miles to the test centre weren't sufficient to 'break in' the cat.

MJ

Yea, takes more than a couple miles to get the cat up and running at peak efficiency. Hold a fast idle (2500 RPM) for about 5 minutes before taking the test when you're there. That WILL get the cat all heated up and ready to go. You can add denatured alcohol to the fuel to lower CO as well if you're just barely not passing on that.