Help me

[Steven Fitzgerald]

Hi can someone answer my question my 98 corolla failed on emissions 1month ago last year it only had 2% co 2 on high idle. And last month it had 57%. Ive changed the excaust and cat converter and lamba sensor and emissions are still high is there any sure way to get to the root of the problem as i want to keep car it only has 150.000 milage.

[FROSTYBALLS]

Moved to the Corolla club.

[olddriver]

Are you using oil, mine doesn't use any and has the same mileage?

[oldcodger]

Hi,

Sounds like you need to take it to a garage that has the equipment to check and tune your car, might be cheaper than replacing parts on a hunch... ?

You could try can of CataClean just before the test or even try a different tester /station as sometimes the operator or machine can cause false readings.

eg the other year, at the same test station and machine,  my readings were near the upper limit and it just passed, yet the year before and the year after they were back to the usual low readings - now was that my car or a problem with the operator/machine ?

[flash22]

first port of call would be a smoke test to rule out any vacuum leaks, then a compression test

Edit. Do you always use the same petrol station ? if you are out in the sticks (assuming Kerry, Ireland is correct) it may be contaminated fuel - Bad fuel can cause incomplete combustion = high C02

take a sample and leave to stand for and hour or so and see if it separates, If so drop the fuel out of the tank and refill with known good

If its a diesel, make sure it hasn't had green put in it

[olddriver]

16 minutes ago, flash22 said:

first port of call would be a smoke test to rule out any vacuum leaks, 

You reminded me that the nuts securing the gas analyser to my exhaust are not stainless and had corroded, causing an audible leak, but I don't know if that would affect the CO2 content.