Bravo 1.2 80SX 16V (99) fail on MOT emissions

[Steve]

Help!
I've taken my Bravo 1.2 for its test and its failed on emissions. It's had a brand new CAT and whole new exhaust, plugs were changed recently, as were the HT leads and power pack. I've checked the air filter this morning and its relatively clean, with no blockages.

There's no sludge in oil cap which I guess rules out water in the oil. It runs fine and as advised I filled the tank up, added a bottle of wynns injector cleaner and took it for a motorway run going through the gears, straight after, then took it directly to the test centre were it was tested straight away.

Here's the technical stuff
It failed on fast idle and second fast idle test, passed on natural idle test

FAST IDLE: CO = 0.60
Engine speed: 2795rpm
HC : Pass
Lambda: 1.038

SECOND IDLE TEST: CO = 0.84
Engine speed: 2480
HC: Pass
Lamda: 1.037

NATURAL IDLE TEST: All passes.

I've got it booked in again in a different garage on Tuesday for a test. Despite having brake pads on front and back replaced they also failed it on them saying, the calipers could be sticking. My mechanic disputes this and thinks the eqipment used isn't geared to older cars. The brake test calibration was last done in September 2011.

Sorry it's long winded, but I think I've covered it all. Any advice gratefully appreciated. I've commited to a few hundred pounds so far and don't want to write it off.

 

[Ted]

There are several possibilites, but the most likely is that you need a new lambda sensor.

Probably a good idea to double check that there are no leaks in the exhaust up to the engine, and that the temperature sensor is working OK.

Ted

 

[Steve]

Emissions

Thanks Ted,
It's now passed, but only just apparently. The mechanic says the lambda sensor's fine as there's no engine problems as such to point towards that being the issue.

There was a compression issue with the car earlier in the year which might have contributed to it. He also noticed it had to much oil in the engine.

Moving forward, is there any point in putting engine restorer in it to resolve any compression issues. My mechanic thinks I should get rid of it but it runs fine, isn't smoking or losing fluids - and has just stood me £450. Only 83,500 miles.

 

[Ted]

I doubt any of these engine additives do anything more than fix the problem for a short while if at all.

If you've got clean oil and the engine is running reasonably smoothly, and not burning excessive oil, I wouldn't do anything.

The car is 14 years old so there are plenty of other things that could go wrong - e.g. has the timing belt ever been changed? But as the car is not likely to be worth more than a few hundred quid, and is presumably still useful to you, I would keep it until the next time it needs an expensive repair, and then think about
getting rid of it for scrap.

Ted