obd1 swap rough idle/no throttle input [video]

ivan leon

New Member
hello guys recently pulled my RUNNING ZC obd1 and swapped it into my 1998 civic i used an ebay jumper harness, It has no CEL idles rough takes a while to start i also cant give it any throttle just backfires and rpms move only by 200, ive replaced fuel filter and pump, with no luck also IGN coil and ignitor along with wires all no luck, all grounds are good ,

heres the vid [engine harness is good]
 

rich_rolla

New Member
Sounds to me it's only running on a couple cylinders try pulling a one plug wire off at a time and see if it stays the same or makes it worse... Also make sure it's wired for multi port fuel injection u have to add 2 wires to the injector wires right inside the firewall and run them to the 2 inactive injectors... If that's the problem I had a dohc zc motor in my crx that was my problem 2 wires saved the day lol
 


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XpL0d3r

I had a Civic once.
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CEL looks like it is flashing code 41 in the video when you first start it. Then it goes away. Code 41 is o2 sensor related.. check on that.

Try jumping the service connector (blue 2p) by the ECU, to see if this code 41, or any other codes shows up. It's possible the issue lies with your ECU or more likely, the eBay ODB2->ODB1 harness.

Also, what ECU are you running?
 


ivan leon

New Member
CEL looks like it is flashing code 41 in the video when you first start it. Then it goes away. Code 41 is o2 sensor related.. check on that.

Try jumping the service connector (blue 2p) by the ECU, to see if this code 41, or any other codes shows up. It's possible the issue lies with your ECU or more likely, the eBay ODB2->ODB1 harness.

Also, what ECU are you running?
hello yes the o2 was previously disconnected code went away. i have a p06 ecu which worked fine last car. A

And yes i believe it is the jumper is there a conversion pinout i can look up?
 

mc360

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Look up both pin outs for both motors (or should I say both cars the motors were originally in) and compare. All a conversion harness is doing is extending the wires to obd1 plugs from an obd2 harness.
 

ivan leon

New Member
Look up both pin outs for both motors (or should I say both cars the motors were originally in) and compare. All a conversion harness is doing is extending the wires to obd1 plugs from an obd2 harness.
will do sir thank you, also are all injectors supposed to fire off at same time?
 

mc360

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Why would all injectors fire at same time? Should fire off in the same order as the ignition
 

mc360

boosted hx
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yea buy a good jumper harness to start with, its running bad now because you are running the motor on the incorrect ecu.
 

XpL0d3r

I had a Civic once.
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OP, I have a used OBD2 > OBD1 conversion harness if you want to try it. It worked fine before I parted out my Civic. Just pay shipping and it's yours.
 


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