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Hi guys,

I have a KL-ZE curved neck inside my 1997 MX-3. It was a B6D (107 HP). Now it is a KL-ZE curved neck with K8 PreFL cable harness and KL31-ECU and K8-PreFL-VAF.
It runs great.

But I have three questions:
1. I get an error "15": O2-sensor left. That means front exhaust manifold. Is it a real error or is it reasoned of my KL31-ECU und K8-PreFL-VAF?
2. When I'll run the engine in diagnostic mode (bridge GND & TEN), the engine starts, but it goes out (stall) immediately. I can "give some gas", then the engine runs and when I take off the gas very very slowly, the engine falls into idle with luck. What could be the reason for it? Could it be a wrong ignition point, the O2-sensor-error, or a wrong idle speed?
But in normal mode (without bridge), the engine runs perfekt. The idle is about 700-750 rpm, very constant. I have no problems. Though I'll check the ignition point to be on the safe side, but I can't get it into a stable idle in diagnostic mode?
3. I have installed the 16V-fuel pump (B6D 107 HP). Is it a problem? Should I swap the fuel pump to a V6-fuel pump?

Could you help me?

THX!

Hi tom

1. Yes, o2 sensor is not functioning correctly anymore. Replace it
2. It should do that (not 100% certain of this)
3. I would recommend doing that if you can get it against a reasonable price. Remember, going from 100/110 to 185/195 engine hp means more fuel is needed. In you case almost a 100% increase of power

Thanks for your anwer.

Could it be a problem, that I drive K8-O2-senosors with the KL31-ECU? Should I use KL-O2-sensors (from KL-DE) instead?

About the fuel pump:
I looked up the repair-manual: The B6D fuel pump pressure is about 4.5 - 6.0 kg/cm². The K8 fuel pump pressure ist 6.5 kg/cm² max.

About the second point (does not idle in diagnostic mode):
Could it be a problem with the O2-sensors? Or maybe an incorrect firing point?
When the engine is cold and I want to start, it also cranks about 1-1.5 seconds. But it cranks fast, really fast, not slow (like with a poor battery). Could it also be a sign for a wrong firing/ignition point? While driving the ignition point is calculated automatically, so there is no problem.

Hi guys,

I looked up the workshop manual for the fuel pump maximum pressure:

fuel pump max. pressure

16V (B6 SOHC) 1991-1993:
441 - 638 kPa (4,5 - 6,5 kg/cm²; 64 - 92 psi)

V6 (K8) 1991-1993:
441 - 638 kPa (5,0 - 6,5 kg/cm²; 64 - 92 psi)

16V (B6 DOHC) 1994-1998:
480 - 657 kPa (4,9 - 6,7 kg/cm²; 70 - 95 psi)

V6 (K8) 1994-1998:
500 - 630 kPa (5,0 - 6,5 kg/cm²; 72 - 92 psi)

So, the fuel pressure of the fuel pump of the B6D (DOHC) ist higher than the max. pressure of the pump of K8 PreFL (1991-1993). So I think, it is not a duty to change my B6D-pump to a K8-pump.
What do you think?

Another question:
Should it be better to install the KL-O2-sensors instead the K8-O2-sensors with the KL31-ECU?
Are there differences between the K8-O2-sensors an KL-O2-sensors (maybe another voltage)?

THX for helping!

Nobody an idea?

It doesn't matter which o2 sensors you install.

You can even use a nissan 180sx (european version) single wired o2 sensor.


Just use the k08 ones and you'll be fine. But replace this one first before attacking the idle problem.


Fuelpomp sounds wierd to me. It would make sense to put a higher performing fuelpomp in a car with 30% less power.


edit: ow yeah... Does it even work with you b6 pomp if you have a k8 harnes?

Okay, I'll change the O2-sensor next week.
Then I'll also check the idle-problem.
Maybe it runs in diagnostics, wenn I start it in diagnostic-mode and then change the ignition-time while the engine starts.



Yes, it runs with B6-FL-pump and the K8-PreFL-harness.

Should be 650 rpm in Diag, TEN GRD jumped. Then it should go up to 700rpm out of Diag. Try adjusting the idle screw top of throttle body. Initial setting is three turns out.
I buy Denso O2 sensors from RockAuto.com $41 bucks with coupon (just Google Rockauto coupons) They're original equipment.

Thanks for the Website.
Because of the idle screw: I have to screw it coplete into the throttle body and then three turns out?
I'll check it.

Three turns is just ball park. Mines about 3.5 turns. Turn it slowly bit by bit untill you get to 650 rpm then take it out of diagnostics and drive it. (always adjust the idle in diag mode) I actually had mine adjusted out too far and my acceleration was sluggish.