Fuel running rich and spluttering from exhaust

Well at least CH (don't know where you get this letter combination CS would be right?) 4G63 reports these kinds of fault codes and it runs newer ECU than 4G69.

When narrowband lambda is reading AFR's like 11, 12 and 13, which are all perfectly normal values on flat out runs on high RPM's the narrowband shows basically nothing. On AFR ~13 it shows some of the upper curves of sinewave which is direct indicator for too rich mixture. For example voltage going from .1 to .2. So when there is some fault that makes the engine run that rich, when it should run stoichiometric, there is sometimes no way for ECU to tell, if the Lambda is broken or not. That's why in some cases it reports lambda broken.

If there is slight under-efficiency I think it is possible for ECU to have it's own code.

^That is one, very considerable alternative for simulator. I would recommend trying that out too. I just had one simulator on my hands and you don't have to solder it if you don't like. You can always get connector's and a few pins and make a easily removable component in between Lambda and ECU.
 
Sorry for the OT, but:
Don't mind about attitude, none taken. But I was told that your chassis number starts with JMBLNCS.. am I right? The two letters before CS may change. So just out of curiosity I asked where does the CH come from. On 7-9 Evo's, they talk CT's (CT9A) and so on.

If I stand correct, chassis number explained (as good as I remember):
J - Manufactured in Asia, Japan
MB - Mitsubishi
L - 5-door (3-door would be M)
N - Manual Transmission (Automatic would be Y)
CS - Body (where I'm referring to)
x-number - Engine, I have 9 which states for 4G63
A/W - A = Sedan, W = Wagon/STW
x-number - Manufacturing year, I have 4 = 2004
x-letter - Manufacturing Plant, I have U (and don't know where it comes from)
Last numbers - Serial number

I don't know all and I have no intend to. As you may see, I'm trying to learn.
 
Ryan said:
Urran said:
Well the fault code doesn't really tell you if the sensor is broken or not. It will tell you does it give figures that it should. For an example if it runs too rich and lambda doesn't read values that ECU would be happy about -> fault code.

My 2nd lambda was complaining that my cat's don't work as efficient, as ECU would like. Still it gave fault code "2nd Lambda sensor". Replacing the sensor really doesn't solve that problem. But datalogging it showed me what was the problem.

And by the way OEM sensors seem to last a fortune longer than non-OEM :) At least from my experience. If you get to know who manufactured the OEM, you might get the same one straight on that brand, cheaper.
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Can't speak for the CH but the CJ doesn't throw error codes for the sensor if it thinks the readings downstream of the cat aren't correct. Instead it throws a P0420 Catalyst under-efficiency error...

My CJ didn't like my headers and through CELs, ended up fixing it by slapping one of these on it:
New_o2_spacer.JPG

http://www.ebay.com.au/itm/O2-Spacer-Ad ... 2a239dc42a
Given how cheap and non intrusive they are I would recommend trying these before going with a device you have to solder into the wires going to the sensor...

But in reply to the OP, if you're getting normal fuel economy and it's not throwing any check engine lights I really wouldn't worry about it.... If you come to the NSW meet on Friday I can whack my scan tool on it and see what error codes it is actually spitting out before and after the run through the RNP...
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I've already had a computer scan done on my car and I got the following three error codes all relating to the 3 oxygen sensor's.

They read:
Total codes: 003
CODE001: P0136 Oxygen sensor (rear)
CODE002: P0135 Oxygen sensor (front) heater
CODE003: P0141 Oxygen sensor (rear) heater
 
I fail to see how all three are fried simultaneously, unless he ran leaded fuel or something :lol:
Perhaps one is cooked, causing the others to function incorrectly throwing up codes for all of them...
 
Well when my cel came on, the front heater o2 sensor which is the one on the exhaust manifold, was the one that was broken. Ive heard they can just get clogged up so maybe soak the metal sensor part in petrol?
 
sladey121 said:
Just go to mitsubishi and have them run a diagnostics scan on it. If you have error codes on your oxygen sensors, then they will need replacing. Don't buy the sensors through mitsubishi, they charge a fortune. Go to bursons or repco or something. They will be much less
Click to expand...

Mitsubishi charge $150 for detecting any type of problem (diagnostics). It's ridiculous!!

sladey121 said:
Well when my cel came on, the front heater o2 sensor which is the one on the exhaust manifold, was the one that was broken. Ive heard they can just get clogged up so maybe soak the metal sensor part in petrol?
Click to expand...

I just realised today, my engine warning light bulb on the dashboard may need replacing :eek:
It doesn't turn on for a few seconds after I turn the igniton to 'ON'. It's the same issue with the 'ABS' light.

So I am not able to see if there are any issues (incl. o2 sensor) with the engine or transmission. :(

According to the 'Owner's Manual' the following lights should turn on after you turn the ignition 'ON': battery, oil, engine and ABS from memory.

If anyone else own's a Lancer CH, can you please confirm for me which warning lights initially turn on?

Cheers.
 
sladey121 said:
My oil and cel lights come one and stay on for like 3-4 secs then disappear
Click to expand...

Okay so the oil and engine lights do. What about the battery and ABS lights?
 
Okay. Looks like I gotta change the 'ABS' and 'CEL' bulbs. Any idea what type of bulbs they take?
 
$390 is a lot of coin for a simple O2 sensor I can check around my sheds and see what I have lying around I am pretty sure I have 2 rear O2 here nit sure about the front one...
 
sladey121 said:
No clue. If the cars spluttering, it won't be your bulbs?
Click to expand...

Yeah I know. It's unrelated but I need to change the bulbs to see if the engine light actually comes on while driving which would then shine some light on whether my oxygen sensor(s) need replacing.

Bulbs > Engine Light > O2 Sensor

It's a pain in the butt I know. :/
 
Before you throw out the sensor, look upstream, could be poor air flow (bad air filter) or poor spark (bad plugs).

In most cases, it's the simple things letting you down, not the ornate...

Worth checking?!
 
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