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Discussion Starter #1
Hello!!

I have catalyc dohc zc engine, with O2 sensor, but i founded and PM7 of non catalyc dohc zc, this will fit on my car and work the O2 sensor (don't break the catalyc converter)???

Thanks!!
 

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Use your original manifolds on the new engine.

D16z5 = DOHC zc with o2 and cat
D16a9 = DOHC zc without o2 and cat

They also have a different flyweel so you might have to change your pressureplate or reuse your old flyweel. Your diskplate goes with your tranny. I believe it was 21 teeth for the z5 and 20 teeth for the a9.

Your ECU will complain if it can't find an o2 sensor. So use your old exaust manifold.

You can use the new intake manifold, but i'm not sure if it's easier than using your old one.
 

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Discussion Starter #4 (Edited)
Use your original manifolds on the new engine.

D16z5 = DOHC zc with o2 and cat
D16a9 = DOHC zc without o2 and cat

They also have a different flyweel so you might have to change your pressureplate or reuse your old flyweel. Your diskplate goes with your tranny. I believe it was 21 teeth for the z5 and 20 teeth for the a9.

Your ECU will complain if it can't find an o2 sensor. So use your old exaust manifold.

You can use the new intake manifold, but i'm not sure if it's easier than using your old one.
I read in some forums that i can try run my vehicle (catalyzed), with empty catalyc converter and connect non catalized ecu, because my catalyzed ecu with empy catalyc converter gives a big CO2 index, and no pass the vehicle inspection (they measure CO2 index).

What do you think?

Thanks!
 

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the PM7 ECU for the cat equipped cars uses the O2 sensor reading to control the fuel mixture for CO - the PM7 ECU for the cars without a cat uses the IMA sensor to control the fuel mixture for CO - to use the PM7 for cars without a cat, you could install an IMA sensor and get rid of the cat - you would need to wire up the IMA sensor, which would consist of switching a couple of wires at the ECU and splicing into a couple of others

the O2 sensor on the cat equipped ECU has a white wire which goes to ECU pin C16 - on these cars the ignition timing connector has a brown wire which goes to ECU pin B20

the IMA sensor on the cars without cat has 3 wires - yellow/white which is the 5 volt reference signal, green/white which is the ground and brown which goes to ECU pin B20 - on these cars the ignition timing connector has a brown wire which goes to ECU pin C16

to use the non-cat ECU, install the IMA sensor and connect the wires as follows:
splice yellow/white wire into yellow/white wire at ECU pin C13
splice green/white wire into green/white wire at ECU pin C12
cut brown wire at ECU pin B20 and connect brown wire from IMA sensor to the portion of the wire remaining in the ECU at pin B20
cut white wire at ECU pin C16 and connect the brown wire remaining in the harness, when you cut it at the step above, to the portion of the white wire remaining in the ECU at pin C16
leave the white wire remaining in the harness not connected - it went to the O2 sensor which you can eliminate or just leave the sensor in the hole in the exhaust manifold as a plug
you could remove the O2 sensor from the manifold and just install a plug in the hole

this is where the IMA sensor is located on the non-cat cars (the IMA sensor has an adjusting screw for adjusting for the CO reading)

 

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Discussion Starter #6 (Edited)
the PM7 ECU for the cat equipped cars uses the O2 sensor reading to control the fuel mixture for CO - the PM7 ECU for the cars without a cat uses the IMA sensor to control the fuel mixture for CO - to use the PM7 for cars without a cat, you could install an IMA sensor and get rid of the cat - you would need to wire up the IMA sensor, which would consist of switching a couple of wires at the ECU and splicing into a couple of others

the O2 sensor on the cat equipped ECU has a white wire which goes to ECU pin C16 - on these cars the ignition timing connector has a brown wire which goes to ECU pin B20

the IMA sensor on the cars without cat has 3 wires - yellow/white which is the 5 volt reference signal, green/white which is the ground and brown which goes to ECU pin B20 - on these cars the ignition timing connector has a brown wire which goes to ECU pin C16

to use the non-cat ECU, install the IMA sensor and connect the wires as follows:
splice yellow/white wire into yellow/white wire at ECU pin C13
splice green/white wire into green/white wire at ECU pin C12
cut brown wire at ECU pin B20 and connect brown wire from IMA sensor to the portion of the wire remaining in the ECU at pin B20
cut white wire at ECU pin C16 and connect the brown wire remaining in the harness, when you cut it at the step above, to the portion of the white wire remaining in the ECU at pin C16
leave the white wire remaining in the harness not connected - it went to the O2 sensor which you can eliminate or just leave the sensor in the hole in the exhaust manifold as a plug
you could remove the O2 sensor from the manifold and just install a plug in the hole

this is where the IMA sensor is located on the non-cat cars (the IMA sensor has an adjusting screw for adjusting for the CO reading)

Thanks a lot for your time!!

I have two engines, one with racing pistons and turbo, pending to mount on crx, it used on stock header a Oxygen sensor, narrowband, now he don't have because have a turbo header.

Then i want to use the 88-89 non catalyzed ecu with this engine on my car.

The ima sensor is only the black item that your photo shows? because my 88-89 comes with this item.

Now i'm stock with 90-91 catalyzed ecu with Oxygen.

If i understand well, for connect 88-89 ecu without catalyzer and O2 on my harness i must do your conversion:

-1º splice white/yellow cable from (new installed ima sensor)??? to white /yellow cable of C13
-2º splice white/yellow cable from (new installed ima sensor??? to white /yellow cable of C12
-3º Cut brown wire connected to Pin B20 of ecu and splice to C16 Of ecu
-4º When cut C16 (white) from ecu, don't need to be connected because is O2 sensor.
-5º Were is the brown wire from IMA? i looked in the 88-89 ecu i see the ima but no the brown cable.


With this method and good ima adjustement i can get a decent values of CO2?? near to catalyc car, because one time i must run on low CO2, for emissions test, now with bad O2 sensor y i do 0.27%, i think that the limit is 4%, many friends that removed the catalyzer measures 2-2.5%.

You are the best! friend

Thanks.
 

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Discussion Starter #7
The last question, if i want to use innovate Gauge with wideband or AEM uego, that have analog output, i can use this with my ecu without modify cables (already have o2 sensor) without cat with any problem??

Connect the analog output of uego/innovate to White (O2 sensor of ecu) cable?

Thanks!!
 

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The last question, if i want to use innovate Gauge with wideband or AEM uego, that have analog output, i can use this with my ecu without modify cables (already have o2 sensor) without cat with any problem??

Connect the analog output of uego/innovate to White (O2 sensor of ecu) cable?

Thanks!!
if you want to control the Air/Fuel ratio with the Innovate or AEM controller, you need to be using the ECU that monitors and controls the A/F via the O2 sensor - the ECU that does not use the O2 sensor won't work for this function - whether you have a cat or not is immaterial
 
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