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Air/Fuel meter

General engine tech -- Drag Racing to Circle Track

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adam728
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Re: Air/Fuel meter

Post by adam728 »

How does the Innovate eat sensors? We run them all the time. And I mean ALL the time. Many hundreds of hours on dozens sensors.

The only time I've had a sensor really fail is doing stuff they specifically tell you not to do, like -30C cold start tests. Hot heater element doesn't like it when a cold engine sends unburnt fuel (opps) or water onto it. Probably not many here running these for cold starts a time or two a day for months on end.
xxdabroxx
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Re: Air/Fuel meter

Post by xxdabroxx »

I'm looking into an auto meter gauge to match the rest of the gauges in the car. They don't fire up the O2 sensor until it sees elevated voltage from your alternator running.
David Redszus
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Re: Air/Fuel meter

Post by David Redszus »

For any lambda sensor, the voltage output (in the rich range) and the switch point
will vary with temperature and with the molecular weight of the exhaust gas.

In the lean operating range, temperature will have little effect and can be ignored. But
in the rich range, where all racing engines operate, temperature has a significant effect
on voltage output but not on the switch point. The switch point voltage will rise with
temperature and will level off at approximately 450oC (842oF) and will remain insensitive
to temperature thereafter.

Thereafter, being until the sensor is overheated and it self destructs. A typical
continuous operating temperature is 600oC (1112oF) and the maximum intermittent
permissible temperature is 800oC (1472oF) all temperatures to include the sensor heater.

Clearly, the accuracy and life of any oxygen sensor is critically dependent on
operating temperature. If too low, readings are inaccurate; if too high, the sensor is
destroyed and is inaccurate. Therefore, the proper location of the sensor in the exhaust
pipe becomes critical. It should be noted that some sensor designs are very sensitive to
excessive temperatures and are easily destroyed if not correctly installed.

In a single cylinder four stroke engine, the oxygen sensor should be quite close to the
exhaust port since it will see a heat pulse only every other revolution. In a single cylinder
two stroke engine, the sensor must be located somewhat farther from the port since it
will see a heat pulse every revolution. If a sensor is positioned in a collector pipe which
combines several cylinder heat pulses per revolution, a longer distance must be observed
to prevent destruction. If a turbocharger is fitted, it will raise the exhaust gas temperature
and the sensor must be relocated accordingly. An exhaust gas temperature probe (Type
K thermocouple) should be used to monitor and determine the correct location of an
oxygen sensor in the exhaust pipe.

Oxygen is not the only substance that will effect an oxygen sensor. The composition
of the exhaust gas has a very real effect on both the sensor switch point and output
values. Gases such a free hydrogen will cause a lean shift in the switch point. Gases
with molecular weights heavier than diatomic oxygen (O2=32), such as most heavier
hydrocarbons (isooctane, aromatics, etc.) will cause a rich shift in the switch point of
the sensor. Some substances such as NO and SOx have very little effect while toluene
and isooctane vapors have a large effect.

In addition to excessive heat, oxygen sensors can be destroyed in several ways. They
can be poisoned with sulfur, phosphorus, silicone and of course lead. They can also
be fractured by thermal shock. Excessively rich mixtures, oil additive deposits, and
excessively low temperatures can foul the pores of the sensor ceramic tip.
Monzsta
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Re: Air/Fuel meter

Post by Monzsta »

adam728 wrote: Wed Apr 07, 2021 10:02 am How does the Innovate eat sensors? We run them all the time. And I mean ALL the time. Many hundreds of hours on dozens sensors.

The only time I've had a sensor really fail is doing stuff they specifically tell you not to do, like -30C cold start tests. Hot heater element doesn't like it when a cold engine sends unburnt fuel (opps) or water onto it. Probably not many here running these for cold starts a time or two a day for months on end.
The sensor may not be defective, but the innovate driver fails. It either overheats the sensor or fails to put enough current to it. either way you end up with a blinking light and a sensor that won't calibrate or warm up. It worked great the first few months I had it.

After buying 3 sensors and having them "fail" in rapid succession I decided the LC2 had failed, after spending more on sensors than the meter was worth.

I'm going to try some of the "dead" sensors with the 14Point7 controller I bought to replace the Innovate. I'll bet they'll cue up just fine.
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Re: Air/Fuel meter

Post by Tuner »

Monzsta wrote: Wed Apr 07, 2021 10:05 pm
adam728 wrote: Wed Apr 07, 2021 10:02 am How does the Innovate eat sensors? We run them all the time. And I mean ALL the time. Many hundreds of hours on dozens sensors.

The only time I've had a sensor really fail is doing stuff they specifically tell you not to do, like -30C cold start tests. Hot heater element doesn't like it when a cold engine sends unburnt fuel (opps) or water onto it. Probably not many here running these for cold starts a time or two a day for months on end.
The sensor may not be defective, but the innovate driver fails. It either overheats the sensor or fails to put enough current to it. either way you end up with a blinking light and a sensor that won't calibrate or warm up. It worked great the first few months I had it.

After buying 3 sensors and having them "fail" in rapid succession I decided the LC2 had failed, after spending more on sensors than the meter was worth.

I'm going to try some of the "dead" sensors with the 14Point7 controller I bought to replace the Innovate. I'll bet they'll cue up just fine.
Why don't you call them and get a return order number and send it back for warranty, they will give you a new one if it is defective.

Likely as not, something about your installation is damaging the sensors, one of the several things David Redszus mentioned, probably thermal shock from wet fuel or water on start up.

I killed a sensor once on a cold and raining like a cow pissing on a flat rock day from water splashing up under the car when driving licketysplit through a deep puddle. Killed two at the same time once when carb tuning a 565 BBC on E-85 on a chassis dyno. Forgot to turn the O2 controllers off when we went to lunch and starting the engine when we came back dumped a manifold puddle of cold fuel on hot sensors ...... my mistake.

I have some sensors that are lazy from being used on engines with the wrong kind of silicone, I keep them separate and only use them on screwball deals I know are contaminated.

I have been using every type of Innovate controller for more than 15 years and have not had any that to my knowledge "kill sensors". Some of the LC-1 controllers have been installed and in service for that length of time on EFI installations and still chugging along. I still have my original LM-1 and it works great. I have a LM-2 and it works great.

In my opinion the Innovate serial chain data gizmos for recording TPS, MAP, RPM, EGT and acceleration G for data logging and analyzing using LogWorks software is by far the best system for a temporary installation to tune carbs, either on a chassis dyno or street driving for fine tuning the cruising. The LogWorks software makes it a winner.

I'm a happy camper, sorry you had trouble.
Monzsta
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Re: Air/Fuel meter

Post by Monzsta »

Tuner wrote: Thu Apr 08, 2021 12:11 am
Monzsta wrote: Wed Apr 07, 2021 10:05 pm
adam728 wrote: Wed Apr 07, 2021 10:02 am How does the Innovate eat sensors? We run them all the time. And I mean ALL the time. Many hundreds of hours on dozens sensors.

The only time I've had a sensor really fail is doing stuff they specifically tell you not to do, like -30C cold start tests. Hot heater element doesn't like it when a cold engine sends unburnt fuel (opps) or water onto it. Probably not many here running these for cold starts a time or two a day for months on end.
The sensor may not be defective, but the innovate driver fails. It either overheats the sensor or fails to put enough current to it. either way you end up with a blinking light and a sensor that won't calibrate or warm up. It worked great the first few months I had it.

After buying 3 sensors and having them "fail" in rapid succession I decided the LC2 had failed, after spending more on sensors than the meter was worth.

I'm going to try some of the "dead" sensors with the 14Point7 controller I bought to replace the Innovate. I'll bet they'll cue up just fine.
Why don't you call them and get a return order number and send it back for warranty, they will give you a new one if it is defective.

Likely as not, something about your installation is damaging the sensors, one of the several things David Redszus mentioned, probably thermal shock from wet fuel or water on start up.

I killed a sensor once on a cold and raining like a cow pissing on a flat rock day from water splashing up under the car when driving licketysplit through a deep puddle. Killed two at the same time once when carb tuning a 565 BBC on E-85 on a chassis dyno. Forgot to turn the O2 controllers off when we went to lunch and starting the engine when we came back dumped a manifold puddle of cold fuel on hot sensors ...... my mistake.

I have some sensors that are lazy from being used on engines with the wrong kind of silicone, I keep them separate and only use them on screwball deals I know are contaminated.

I have been using every type of Innovate controller for more than 15 years and have not had any that to my knowledge "kill sensors". Some of the LC-1 controllers have been installed and in service for that length of time on EFI installations and still chugging along. I still have my original LM-1 and it works great. I have a LM-2 and it works great.

In my opinion the Innovate serial chain data gizmos for recording TPS, MAP, RPM, EGT and acceleration G for data logging and analyzing using LogWorks software is by far the best system for a temporary installation to tune carbs, either on a chassis dyno or street driving for fine tuning the cruising. The LogWorks software makes it a winner.

I'm a happy camper, sorry you had trouble.
The OEM's don't have this problem. But they also tend to use NTK sensors, which are vastly more rugged then the Bosch sensors. Unfortunately aftermarket wideband controllers that utilize the NTK sensor are few and expensive.

I'd be happy with an old AEM with the old Bosch sensor. The new ones are just too fragile.
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Re: Air/Fuel meter

Post by F-BIRD'88 »

Ngk NTK AFX Powerdex AFR METER # 90067 google it
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Re: Air/Fuel meter

Post by David Redszus »

We have sold hundreds of Bosch LSU 4.9 Lambda sensors for racing applications with data loggers.

All sensors will age over time, which will cause a shift in accuracy. For critical tuning they should be
checked against a known gas for accuracy, per Bosch tech info.

We have found two common modes of failure: overheating due to poor placement or incorrect heater
management, and fuel fouling.

Lambda sensors do not like to run rich like some racers do. A rich mixture (especially when coupled with
leaded race gas) will fail sooner than with a mixture that burns more completely and cleaner. Oil fouling
is a related matter as well.
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Re: Air/Fuel meter

Post by F-BIRD'88 »

This is why you might run a NB to monitor with and save the WB for just brief tuning sessions when really needed.
as I do..
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