When the engine is at normal temp say after cruising for 20 minutes, does the CTS sensor have any influence on the ECU? I mean when the resistant of it has become below a certain value because the engine is warm enough, does the ECU still uses the value?

The reason I ask because my car is running very lean when the engine is cold or hot. Have tried a numerous of thing, but still haven't found what's the reason.

Rewired the fuel pump, checked the fuel pressure and all is fine.

Hope someone can help me with the question about the CTS.

 

It uses it at all times the ignition is on.

 

Thanks Stu,

I tried to get this answer by users on PF so I didn't had to disturb you again...

So can it be that if this CTS hasn't got the right restistant through the whole range (say for about 15 % less resistant from cold to high temp) it's leans the engine from cold start to hot?

And is the CTS more for fuelling and the ATS more for advancing the ignition?

 

the coolant sensors normally either work or not, they don't tend to go out of range. it's only a simple NTC resistor.

when they don't work and have an open circuit, the ecu reads that as cold and richens the mixture, not the other way around

 

I measured the resistant of the CTS when it was cold and hot:

Cold is 4,79 kOhms, warm is 215 Ohms

The ATS is at cold 4,51kOhms (Tamb= 16 degree Celsius).

To give you an idea how lean the car runs at full boost (greens, 1,3 Bar etc):
at 3000 rpm it says 15,09:1 (1,02)
at 4000 it says 14,41:1 (0,98) and
at 5000 it says 13,82:1 (0,94)

So that it didn't meld anything is a miracle!

 

those afr figures don't tell us anything about it being dangerous unless you tell us other things like boost


the resistance vs temperature of the act and ect sensors is roughly as follows:

resistance = 0.0036 * temp ^ 4 - 0.109 * temp ^ 3 + 1.2462 * temp ^ 2 - 6.7031 * temp + 15.289

hth

 

Don't have a clue how to read this formula of you...

Maybe if I put up a dynosheet of my rolling road session it tells you a lot more, peaks at 1.5 Bar, holds 1.3 Bar

T3, SS exhaust, greens, msd chip, 3 bar map sensor and -31 actuator:

 

 

YBJ sorry, made a mistake with it.

i used excel to plot the data of the resistance vs temperature data as below and asked it to add a trendline with equation but it was bullshit.

ignore the formula, and just read off the values from the chart.


http://img.photobucket.com/albums/07...CTECTGraph.jpg

you will see that your measurement of is correct

if you want to check that your sensors are working, MSD now sell some software so that you can connect your ecu to a laptop computer, called IAW Monitor. get in touch with stu, or see this topic

https://passionford.com/forum/viewtopic.php?t=206547