Cat problem?

[N947TPL]

Djhh

[Alan M]

Do you have any lights visible on your dash when the car is running? It sounds as if there may be a sensor problem causng a very poor running car. You can get your fault codes read for your car to see if any problems are evident and causing the problems you are having. If your car is a pre OBD model you can read the codes yourself fro the diagnostic block in the engine bay by following this linkhttp://volvospeed.com/Repair/a2.html. If your car is a 96model with the OBD plug under the coin holder follow this seperate link, you will need to make a code reader thoug to read the flahes (I use a multimeter)http://www.volvoforums.org.uk/showthread.php?t=42315

[N947TPL]

Ddd

[timbo_1975]

A figure of 6.8% is not going to be brought down by a new cat for starters!!! These things will mostly pass the emissions test with no cat fitted at all, so begin with a stage 0 tune.

My first port of call would be thermostat, and CTS replacement to make sure a) she is warming up properly, and b) the ECU knows what temp it is at.

You may also have a dripping injector or two, but start with the basics...


tim

[N947TPL]

Ddd

[Alan M]

If the coolant temp sensor is at fault your car could be being fooled into thinking it is cold and the car is in a cold running cycle causing it to run very rich when warmed up. I would definately try to read the codes before any work so you can see if a problem is there. Volvo used their own special code reader to read codes on the OBD plug so if the garage you are using does not have the specific tool for that job they will not be able to pull up any codes or information.

[nobananas]

When you had the emissions test you should also have a reading for Lambda as well. Unless your vehicle has a post cat Lambda then a faulty Lambda is unlikely to throw a MIL (unless the heater circuit has failed). Usually with emissions if the Lambda's passed but the CO hasn't suspect the cat, (your readings however for CO are far to high to be just the cat.) And if the Lambda and CO have both failed then suspect the Lambda sensor. Faulty Lambda sensors can also cause poor running at tick over and constant RPM's (ie when cruising) which will then disappear under wide open throttle or part throttle but not always particularly if they have failed causing an over rich mixture (a lean mixture tends to create a worse effect). A duff temp sensor will also cause similar problems though !

[5seaterT5x2]

Hi there, I could really do with some help.

I've taken a recently purchased 850 t5 auto 1996 n plate for an mot and amongst other things it has failed on the emmissions. The CO reading is 6.8.

has anyone got any suggestions what this could be? The car is only averaging 11.3 mpg and the performnace is far from what i was expecting from a T5.

the bosst gauge only goes about 2/3 mm into the white. could the problems be related?

any suggestions greatly received coz i've only got 10 days before the re-test.

I've tried locating a second hand cat but the only ones available locally are for a 2.5 on turbo. would this fit my car?

stick a decent bottle of injector cleaner (FORTE) in the tank and some decent shell v power fuel. could well be a faulty lambda sensor bad news is from volvo bout £175/180 i did mine the other day. there's a mob on ebay doing bosch ones for a lot less but the firm is hopeless and you gotta work out for your self which one you want ;-/ but over a £100 saved if you can sort it and bosch is a decent make. plenty of forte on fleabay

[nobananas]

Bosch are indeed OEM on Volvo IIRC. Try eurocarparts, I believe they stock Bosch ones.

[N947TPL]

Ccc

[N947TPL]

Ccc

[nobananas]

I think the ect sensor that the management system uses is a diferrent one to that used by the gauge but I could be wrong.