Petrol Smell, Stalling .. But Quick Otherwise

[kyepan 291]

thats a fair comment, as i would love to stick a wide band lambda up its ass and find out what it's really doing fuelling wise. but the problem is so intermitent, i bet that it won't surface during the rolling road session. I'm even tempted to weld a boss on and get one in the cabin to catch it when it does. How much and where can i get one?

[kyepan 291]

another set of tests another set of results

tested things from cold this time

 

Coolant temp sensor CTS:

backprobed with ignition on, 3.85v perfect for the ambient temperature of 5-10 degrees.

 

Idle Speed Control Valve ISCV

Backprobed when running from cold, 4.62v, should be 6-6.5v for cold and 7-9v for hot.

does anyone know why this might be low or how a low value will affect things.

 

Managed to get it to stall by simply blipping the throttle a couple of times, stab stab , die... restart stab stab die... needed throttle to restart when it was turning over after stalling the second time which means its... rich?

 

Air flow Meter AFM

Backprobed and again fine and within tolerances, 5v reference input voltage and fairly ok output voltages, occasionally idle (which should have a 0.75-1.5 range) dipped to 1.07v when it stalled, but was usually around 1.2 at idle.

 

Air Temp Sensor ATS:

Backprobed when not running and running, 2.56v across pins 4 and 5, which means the ecu thinks the ambient air temperature is 30 to 40 degrees celcius.

It should be nearer 4.0v, a resistance check of the sensor terminals itself showed 4200 ohms this corresponds to the correct ambient temp of 5-10degrees.. also resistance via backprobe of connector was again 4200 ohms.

 

Now i don't understand how pin 5 on the AFM can be both the supply voltage and the signal voltage.. pin 4 is earth.

 

So it would seem either that it's a wonkey input voltage to pin 4.. or i'm testing the wrong terminal / wrong.

 

confusd.

[Doof 11]

I'd just like to point out as well that since my RR session i haven't been able to smell petrol once! I really think an RR session can do wonders for an old car and would urge anyone to just book it in and reap the benefits! I spent about 2 years getting high on fumes from this damn car, now its just perfect!

[kyepan 291]

mine doesn't have a dizzy though its an MI on motronic management. Perhaps your right though.

[kyepan 291]

Right, its the morning, going to look at it before training....

 

Think it's worth checking the resistance of the CO pot (idle mixture) , and see if its rich or lean.. as too rich an idle mixture may (when added to the cold start fuelling which seems to be my are of issue) make it toooooo rich.. and make it stall.

 

Resistance of pins 1-4 should be between 270 - 520 ohms, and the voltage from the CO return should be between 1.95 and 2.95v respectivly. clockwise to richen the mixture, and anti clockwise to lean. lets go have a look, after a cup of tea and some scrambled egg on toast.

[kyepan 291]

result is, higher voltage is richer... mine read 2.85v, so pretty rich.. leaned it off to 2.15v but it made no difference to the idle, blip the throttle and it tried to die.

 

Took it for a quick spin to warm it up and check the warm idle, and it seemed smoother and quieter,

 

Am i correct in assuming the idle adjustment is only taken into account when the throttle is in the closed (click closed) position?

Edited March 29, 2008 by kyepan