Tom M'Guinn

My Zeitronix is acting funning. The A/F ratio read-out is slow to respond and/or non-responsive -- it will sit on a number (e.g. 14.x) for seconds on end even if I rev the motor, floor it, decel with clutch engaged and throttle closed, etc., -- only to move a few points every now and then. This just happened out of the blue. It was working fine yesterday, and I haven't touched a thing.

I'm assuming the sensor is shot -- has anyone else experienced this?

Perry 951

Heater in the sensor went bad, or there is a "PID" lock in the unit where power is not going to the heater element. My TechEdge unit does this once in a while.

Tom M'Guinn

Interesting. Just took it out again, and it seems fine...

What's a PID lock?

Perry 951

Don't know if the PLX works the same as the WBO2, but PID lock for me means:

"A PID unlock is not necessarily an error, but it does indicate either very rapid changes in heating or cooling of the sensor, and/or rapid changes in the ambient air-fuel ratio. If this occurs without an explanation (such as rapid changes in throttle position) then it may be an indication of an intermittent somewhere in the wiring, or an aging sensor, or the sensor is positioned where it is either too hot or too cool."

In other words, the heater in the sensor requires voltage above or below normal thresholds to operate. As the sensor ages the heater will require more or less voltage to operate in the same parameters the unit is looking for.

333pg333

That's interesting Tom as mine just froze yesterday on 14.7 and the rest of the readings, and has refused to budge since. Even if I turn the car off and on again, it goes through it's greeting, says it's warming up, and then straight back to that last display even though the engine's not running. It's all pretty new to me and I don't have my instructions with me, but what is that small blue button on the r.h.s. I assumed it was a reset button but it didn't change my readout. I only had the unit in for 4 days. Was working fine before that.

xsboost90

if its a zeitronix zt2 the button on the rhs will display the most lean/or rich that the a/f readings were- kinda like a tach memory.

333pg333

Right. That makes sense as it displayed the same readings so that's all it remembers. Sound's like something is wrong with the sensor.
Thanks Dan.

Patrick

kasturbo

Funny, my zt-2 has also been acting flaky lately. I have to restart the car once for it to read 14.7 at idle. When driving I either get no change at wot or it goes straight to 21 meaning it's out of the range. The car smells rich, so I know it's not going that lean.

RKD in OKC

I've had to replace the O2 sensor on my ZT. It had what seemed like slow response and would display different AFR values by just turning car off and back on driving down the highway.

333pg333

So how would mine become frozen after just 4 days? Would a big oil leak that involved blow by resembling 'Puffing Billy' have something to do with it?

kasturbo

Has anyone contacted Zeitronix about this problem or is this normal wear with these sensors?

evil 944t

I did and I'm waiting for them to reply. I'll give them one more day and then I'll call.

944CS

how many hours on the sensors? And is it a Bosch or NTK?

evil 944t

Here is the reply from Zietronics in regards to Patricks problem.

"If this is a new O2 sensor then a connection is missing between the O2 sensor and the Zt-2. Inspect the O2 harness. Look very closely at the RJ45 style O2 harness connector plugged into the Zt-2. Inspect the clear plastic, make sure it does not cover the gold pins. It may been damaged when pulling through the firewall."

update, they also said when the o2 goes bad, it will also get frozen @ 14.7. So try swapping it out with a good sensor and check the connections.

evil 944t

Patrick's only has 4-5 days on it.. so, its brand new. It came with a Bosch sensor.