Will a failing lambda always give fault code as i have a cold runnning issue and my mapper thinks it could be lambda taking time to heat up

 

Bump for info

 

Hi there

Not always failed lambda will give you error/CEL,but this depends on the ECU,assume are you on stock OE ECU or are you on AlcaTek ?

One way how to check is with multimeter or to borrow good Lambda sensor

Thanks,Jura

 

Yes on oe ecu and my jdm twinscroll lambda is different from single scroll i think will try testing with multimeter

 

Jura would maf cause same issue as i cleaned it on wednesday and car seems better today

 

Hi there

I would say,yes MAF can cause poor running,but cold starting can be the Lambda or Coolant Temperature Sensor can cause this too

Thanks,Jura

 

Cheers jura car starts first turn of they key just splutters when driving till it heats up

 

Hi there

I would suspect then Lambda or Coolant Temp Sensor,those two things can cause those things

Do you have Torque app if yes then monitor Coolant temperature and Lambda hardly you can monitor via OBD as they don't read as wideband

Thanks,Jura

 

Will use ssm to monitor as torque wont allow anything but code check/erase on jdm car for some reason

 

That's strange about the Torque,but you can try SSM monitor and you will see,please if you could monitor Coolant and Lambda

Thanks,Jura

 

Torque Worked fine on my uk sti but i dont think jdm ecu allows enough access

 

I didn't tried on JDM cars Torque,but I will check on my friend car

Thanks,Jura

 

Ok so car is still stuttering when i drive from cold took lambda out is it supposed to be this colour

 

looks rich

peter, you want me to put the psi3 monitor on it to reset and read codes and check to see what the ecu is seeing in real time

 

Where abouts are you neil

 

I have ssm software but it doesnt read front lambda

 

the front lambda is the wideband , i would say the front lambda is gubbed

i would confirm it using another monitor

 

glasgow peter

terzo neil from other site here

 

Thought it was you neil if you could check it that would be great

 

pm me your number quick chat before sleep

 

yeh that looks pretty rich, mine went a similar way before the heater circuit died in it and it threw a code. Was bananas at cold start for a few weeks beforehand though.

If you can run the freeSSM software you can probably run romraider logger which will be able to show you the front o2 readings.

 

All sorted lambda replaced

 

My 03 uk Sti has a strange stutter/hesitation missfire when cold for the first half mile then clears also uses a LOT of fuel when cold or crusing it uses less when it gets the boot when it gets the boot! I was thinking of replacing the front lambda does this sound like what yours did? Also how hard was it to remove I've heard they can be a pig?
Any advice would be much appreciated
Cheers
Mark

 

Exact same issue mate but forgot to bump this mine is worse its now choking have changed
Cts
02 sensor
Maf sensor
Coil packs/plugs
Still not fixed

 

Have you cleaned the idle control valve?

 

Sorry forgot that mate yes did it twice

 

Cold start mapping issue?

 

Have dropped it off at the mechanics to have a look then if he doesnt find anything then mapper after that

 

This started on mine after I ran a exhaust bung for a couple of days this started and I noticed the turbo temps were a lot higher when using it so I took it out
Do these have a exhaust temp sensor could that be at fault during closed loop operation also you can feel it switch to the map when you floor it then it runs mint or when it's warmed up