combustion in vitara sidekick

[pedrov]

I am a Vitara Sidekick 1998 owner, with almost 220.000 kms., and need some technical help:
1.- at the last combustion analysis the main parameters measured, indicates clearly that for the next test (next year), it will be sure that my jeep will not success. These are the values:
@2500 RPM, HC (ppm) 72 (max allowed 100)
CO (%) 0.43 (max allowed 0.5)
CO+CO2 (%) 14.51 (min allowed 6)
Idle condition, HC (ppm) 91 (max allowed 100)
CO (%) 0.48 (max allowed 0.5)
CO+CO2 (%) 14.52 (min allowed 6)
Do you think I have to change the catalytic converter and other parts (which parts), or only make some adjustments to the injection system?
2.- eventually, 2 or 3 times a year, some strange noise appears for a couple of minutes closely to the right air bag, near the front right passenger. it seems to be some electrical noise, like sparks, but I can not be sure. what do you think?

[11_evl]

hydrocarbons of 71 is very good from what i no. and a co of .4 is fine. but yes the co should be lower if not 0% meaning your cat canverter mite be blocked and need replacing

[MUD-PIGSIERRA]

I hear running the Catalyctic Converter as early in the exhaust system is also the most effective in burning harmful gasses as it gets hot as quick as possible.

So getting it mounted straight after the extractors from the engine would be the best. So maybe a new cat as suggested might help in the testing for next year. Some new cars are even running two these days.

[11_evl]

I hear running the Catalyctic Converter as early in the exhaust system is also the most effective in burning harmful gasses as it gets hot as quick as possible.

So getting it mounted straight after the extractors from the engine would be the best. So maybe a new cat as suggested might help in the testing for next year. Some new cars are even running two these days.

if they are mounted too close they burn and melt internally so i have read somewhere

dont quote me on that. mine is mounted about 25cm after all pipes join into one

[Gwagensteve]

I hear running the Catalyctic Converter as early in the exhaust system is also the most effective in burning harmful gasses as it gets hot as quick as possible.

So getting it mounted straight after the extractors from the engine would be the best. So maybe a new cat as suggested might help in the testing for next year. Some new cars are even running two these days.

if they are mounted too close they burn and melt internally so i have read somewhere

dont quote me on that. mine is mounted about 25cm after all pipes join into one

Not if the car is running properly (i.e not way too lean) If it has an operational O2 sensor and is running in closed loop on cruise there's no way it should cook the cat.

My STi has 2 cats, one is within a few inches of the turbo. Generally, the reason for 2 cats is that the one closest to the motor is small and reaches operating temperature quickly to cover emissions from startup.

Steve.

[MUD-PIGSIERRA]

if they are mounted too close they burn and melt internally so i have read somewhere

In most cases a melt down only happens with high levels of unburnt Hydrocarbons getting to the cat, Pedrov's level does not seem to excessive...? A lot of the newer 4bys/cars have sensors to worn of this mostly through a engine light.

I dont know of Pedrov's fuel quality where he is but running Leaded fuel through the cat can also stop in from being very effective as well. Most cat coverters are ceramic coated these days so a new 3-way Catalytic converter would probably be the fix though...

[Gwagensteve]

if they are mounted too close they burn and melt internally so i have read somewhere

In most cases a melt down only happens with high levels of unburnt Hydrocarbons getting to the cat, Pedrov's level does not seem to excessive...? A lot of the newer 4bys/cars have sensors to worn of this mostly through a engine light.

I dont know of Pedrov's fuel quality where he is but running Leaded fuel through the cat can also stop in from being very effective as well. Most cat coverters are ceramic coated these days so a new 3-way Catalytic converter would probably be the fix though...

Are you sure about that Mud-Pig? "Cat protection mode," when triggered, on modern ECU's, runs the car amazingly rich and to cool the exhaust (?) - I have seen this on a dyno.

Steve.

[MUD-PIGSIERRA]

Are you sure about that Mud-Pig? "Cat protection mode," when triggered, on modern ECU's, runs the car amazingly rich and to cool the exhaust (?) - I have seen this on a dyno.

Steve.

Im not sure about anything Steve... When you say 'Cat protection mode' and running the car amazingly rich are you saying that this fuel is not being burnt...? My understanding is this was done to cool exhaust but the mixture was still burnt....?

What Ive read in a old Motor Engineers magazine that I used to get. And i cant find it now but Im pretty sure it mentions greater than normal un-burnt air/fuel mixes as causes to Cat melt downs...?

Ive also read some where that cleaning out build up in cats is also done through what you have said above, running the car very rich to burn everything out, which then contradicts running high levels of unburnt hydrocarbons...?