sweanders

To clarify: Is your AFR at 17.5:a with the factory o2-sensor connected and 13.6:1 with it disconnected?

If this is the case I'd start to look for vacuum leaks. What is your cars vacuum reading at idle?

DLS

yes thats right anders.

my vacuum is around 32-36cm/hg on my autometer Boost / Vacuum

sweanders

Any exhaust leaks before or near the O2-sensor?

DLS

hope not, i have mounted every thing with new gaskets and exhaust paste

DLS

can i disconnect my o2 sensor and run the simulated narrowband output on my zeitronix instead or is it to slow?
which pin do i connect it to in the dme in that case?

Laust Pedersen

DLS, It sounds as if your narrowband O2 sensor is “lying” to your DME, which will happen if the engine block has a bad ground connection.

Laust

DLS

Thanks Laust for the tip
any special ground to look at?

333pg333

Laust, any tips if the Zt2 freezes the readouts? Mine is stuck on 14.7 even if the engine is switched off. It's only been installed for 4 days. It was working fine up to then.
Patrick

Laust Pedersen

DLS, The ground connection on top of the bell housing, which a leaky heater valve can drip on, is the most likely culprit.
You can easily test the “bad ground” theory out with a jumper cable between the engine block and the chassis.

333pg333, unfortunately this falls in my “not been there, not done that” category.

Laust

DLS

theres nothing wrong with the ground i think.
i can only get 0,2v from the o2 sensor at idle, sound defect to me?
the car seems to run fine under boost but to lean at idle

I´m thinking of testing my ZT-2 as narrowband o2 but which wire should i connect it to in the dme (pin24) ?

DLS

i did the writeup on clarks-garage how to adjust the idle and the idle screw was way off.
when i jumped the isv the AFR suddenly got rich??
but as soon as i took off the jumper the AFR got lean again ???????
is it something wrong with my isv??