Simulated Narrowband - im over it

I've now installed the narrowband sensors into the exhaust, now for the wiring.

The adapter harness only has one o2 wire in it, so i need a 7 additional pins for a 99 ecu ....

I can't find a definitive 99 ecu pinout guide, but as far as I can tell,

pin 3-4 for front heater
pin 26-27 for rear heater
pin 71-72 for front sensor
pin 73-74 for rear sensor

is this correct? and if so, what order are they? 71 for sensor ground and 72 for signal? 73 for ground and 74 for ground?

if you put the wires the wrong way for the heater is that a problem? if so, what order?

Does anyone have wiring diagrams for a 99 ?

If anyone could trace each o2 back to the ecu - that would be great!

Glen

You have to be very careful about front/rear definitions. Here is what I have confirmed.

Quote:

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The right bank is 1,3,5 and the left is 2,4,6. So according to the service manual my 1995 harness has:

Front (O2 housings)
Right bank - pin 75
Left bank - pin 76

Rear (O2 in downpipe)
Right bank - pin 60
Left bank - pin 79

According to what I can find the 99 ECU needs:
Front (O2 housings)
Right bank - pin 72
Left bank - pin 71

Rear (O2 in downpipe)
Right bank - pin 74
Left bank - pin 73

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Regarding the heater circuits, only the 98-99 have them wired independently. The earlier years all had them bussed together to a common power line. I have a 95 but I did not bother changing the heater wiring and I have to turn off the periphery where it allows the O2s to be tested by pulsing the heaters.

This is from Brett's Clone ECU page Factory Diagrams | THE ORIGINAL VR4 Clone? ECU

http://www.cloneecu.com/wp-content/u..._1998_1999.pdf

today I finished the dual o2 sensor mod.

Its works 100% better, no more miss at 2-3000rpm. Better in every way. Only taken it for a 10min drive, i'll report back in a few weeks.

What a pain it was, 2 x 02 bungs, o2 sensors, 8 x wires....

Glen

Its been a week of driving now and I have to say that the o2 sensors have fixed the issue.

Greg - I would take out the rear only option from chrome. It just doesn't work properly. I tried with simulated innovate, plx and just one stock sensor, all had issues.

Glen

Quote:

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Originally Posted by jazz9

Its been a week of driving now and I have to say that the o2 sensors have fixed the issue.

Greg - I would take out the rear only option from chrome. It just doesn't work properly. I tried with simulated innovate, plx and just one stock sensor, all had issues.

Glen

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It comes that way from the factory. ;)

Yeah general consensus is to stick to dual narrowbands for best drivability.

Factory option? Is that for that Jspec versions?

Still - maybe a note that it will cause issues, I would have saved a lot of time.

When I say to misses between 2-3K rpm, its a major miss and only at light load. It occurs even when the wideband is showing 13.x afr. Its very odd, like the ecu cut ignition for 1/2 sec.

Glen

A mate is installing a jesters pnp ecu into his Magna/diamante with gto engine and was planning on only running the 1 widebsnd sensor. I told him to install a sensor on each bank. I was also under the impression the factory ecus only see nartowband. Is this correct? Or could he run 2x widebands and the ecu will work fine?

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Have him put an OEM narrowband in each bank.

That's what I told him to do but he said the write up for chrome said to use a single wideband.

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That's for logging purposes only.