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Discussion Starter #1
I installed the new megan header & y pipe, a lot of code come up so i bought the o2 sim.
i put the o2 sim to trick the ecu.
everything is fine, all the code from bank1, 2 's sensor gone off after i put the o2 sim except the p0125.

My setup is no bank2 sensor 1 in my car, I spliced the b2s1 singal to b1s1 & b2s1 heater to b1s1 heater in the ecu.

Then, the p0125 insufficent coolant temperature code is the only code not going away, then i replace the themostat & flashed the coolant.
Then i think maybe my b1s1 going bad, so i purchased another bank 1 sensor 1 (used, but still in good condition) & i expected the code will gone away after this sensor replaced the old one.

The code still not gone, I am so sick about the cel and lose of track. I don't know what i can do...................Help pls.........
 

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Discussion Starter #3 (Edited)
yes, now only have p0125 left, insufficient coolant temp in closed loop
also, after the car started for 20mins, the lower hose of the radiator still not warm and my cluster inside the car (coolant temp) is pointing to C or below C when i start the car, is that normal?
thank you
 

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This information is from ALLDATADIY.com. I probably shouldn't post it like this, but I think it's an excellent service, and people need to know how damn useful it is when troubleshooting codes like this.

I highly recommend getting an account, it's only $25 for a year, and it's like getting the entire factory service manual with all the codes, schematics, and troubleshooting information (if you don't know, the factory service manual set will cost you over $200 to buy. $25 is a steal.) Check it out @ http://www.alldatadiy.com/


DTC P0125 Insufficient Coolant Temperature for Closed Loop Fuel Control
http://my.is/forums/attachment.php?attachmentid=4933&stc=1

A thermistor built into the engine coolant temperature sensor changes the resistance value according to the engine coolant temperature. The structure of the sensor and connection to the ECM is the same as in the DTC P0110.

If the ECM detects the DTC P0115, P0117 or P0118, it operates the fail-safe functions in which the engine coolant temperature is assumed to be 80 °C (176 °F) .
http://my.is/forums/attachment.php?attachmentid=4934&stc=1

INSPECTION PROCEDURE

HINT:


If DTCs P0115 and P0116 are output simultaneously, engine coolant temperature sensor circuit may be open. Perform a troubleshooting of DTC P0115 first.
Read freeze frame data using hand-held tester or OBD II scan tool, as freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was lean or rich, etc. at the time of the malfunction.
 

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Discussion Starter #6
thanks a lot for the input, do you know how much for the coolant temp sensor?
just want to know how much i need to spend, thank you..........
 

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toronto1234 said:
thanks a lot for the input, do you know how much for the coolant temp sensor?
just want to know how much i need to spend, thank you..........

Coolant Temp Sensor
OEM Part Number 8942230030
Price $54.73

Should take about 1.4 hours to install, skill level B (whatever that means lol)

Seriously. I recommend getting an AlldataDIY account. It has tons of info.
 

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SLayerS said:
Great website, Das! :)

It's completely worth the $25... I have accounts for both my IS and my beater... first make/model is $25, then additional ones are only like $15 a year.

Does it sound like I'm advertising it?

I AM. It's freakin useful. :p
 

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You do NOT have a coolant problem. The po125 is a original obd2 code and is very misleading but was never change. The code should read <PO125 Insufficient Temperature For Closed Loop Operation. Your problem is going to be in you O2 heaters (frt bank). I am not sure you had to hack the front O2 heater circuits, but it you are driving 2 O2 heaters with one bank then you are possibly splitting your heater voltage in half. Let me know exactly what wires you have tapped and i can try to help. If you what to replace the coolant temp sensor you can, But it wont help your MIL condition..
 

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lextec10 said:
You do NOT have a coolant problem. The po125 is a original obd2 code and is very misleading but was never change. The code should read <PO125 Insufficient Temperature For Closed Loop Operation. Your problem is going to be in you O2 heaters (frt bank). I am not sure you had to hack the front O2 heater circuits, but it you are driving 2 O2 heaters with one bank then you are possibly splitting your heater voltage in half. Let me know exactly what wires you have tapped and i can try to help. If you what to replace the coolant temp sensor you can, But it wont help your MIL condition..

Thanks lextec... hope this fixes his problems, and goes to show you can't solve all your problems just by reading a book.

Let us know how it turns out toronto
 

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Discussion Starter #13
can anybody confirm what i did is correct?
b2s1's heater spliced to b1s1's heater, then taped the b2s1 heater
b2s1's signal spliced to b1s1's signal, then taped the b2s1 signal
anyone can confirmed that is right if take out the b2s1 sensor off the car?
pls.......pls
 

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so do you have to do all of this cutting and splicing to the o2 sensors to replace header,downpipe?what is the point?
 

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Discussion Starter #15
i don't know it have too much cutting & splice....before i bought the header, right now is so much headache...man
 

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weston22s said:
so do you have to do all of this cutting and splicing to the o2 sensors to replace header,downpipe?what is the point?
Well, this is his problem:

My setup is no bank2 sensor 1 in my car
Usually if you have all your sensors, all you have to do is solder 3 points and screw down another to do a header.

To do a ypipe (DOWNPIPES ARE FOR TURBOS NOT NA!!! lol sorry) you don't have to do any electronics... just 5x14mm bolts and moving an o2 sensor (7/8 wrench) to the new pipe.
 

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toronto1234 said:
hELP ......PLS.......CAN ANYONE CONFIRM WHAT I DID THE WIRING IS CORRECT?
B2S1 TO B1S1, AM I CORRECT?

Should be right according to the FAQs posted at the top of the forum... maybe sophie can drop in and confirm.
 

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What I would do is keep your b2 s1 plugged up(you can tie stap it up somewhere on the car since you dont have a bung to screw it in to) then reconnect the heater circuit as it was. Just make sure you dont strap it to anything that could melt as the heater will still be working. Your signals should be ok. By the way, what type headers do you have?
 

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lextec10 said:
What I would do is keep your b2 s1 plugged up(you can tie stap it up somewhere on the car since you dont have a bung to screw it in to) then reconnect the heater circuit as it was. Just make sure you dont strap it to anything that could melt as the heater will still be working. Your signals should be ok. By the way, what type headers do you have?

Heh... and it will get hot enough to melt parts of wiring harness... :blush:
 
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