Obd2 b16a2 EK4 P2T (code 21, code 6)

Hello, I have an EK4 Vti that came with the original b16a2 obd2 but spun a rod so I sourced another b16a2 and I'm getting codes 21 and code 6. I found a cut wire on the thermostat plug and got it re soldered, due to the fan not kicking on. Now the fan kicks on but the code still appears (code 6). As for the code 21, my engine does not come with a oil pressure sensor and it has a P2T ecu. I tried checking for continuity from the ecu pin to the vtec solenoid and the multimeter beeps and checked for ohms showing 31 ohms sometimes 32, 33 fluctuating. So I'm guessing everything is ok. When I de-pinned the wire from the vtec solenoid and attached it straight to the wire coming off of the top of the vtec solenoid cap, the code went away, but came back again. If I could remember correctly with the old engine vtec did work. I'm just lost at the moment, is there any way I could test the ect sensor or sending unit to the cluster or thermostat ? Also I was getting a tps code 7, but just removed the connector and reinstalled and that went away. Any info would greatly be appreciated.

Download this , honda service manual for B16A2 and d16

https://www.dropbox.com/s/q41ol685ttkrzvu/honda civic 96-00 service manual.pdf?dl=0

That will tell you how to do every test you asked about,
Use search, and type key words, TPS ECT sensor test and so forth.

Leej8 said:

That will tell you how to do every test you asked about,
Use search, and type key words, TPS ECT sensor test and so forth.

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Thanks Lee, I appreciate it.

No problems mate.

Hello I'm back again, I found these harness grounds, are they all grounds or what ? 2 wires are brown with a black line, and 3 wires are all black.

So I've linked all of those wires to the thermostat housing for grounds. I've checked the ect sensor plug feeds out 5v, I've checked the ect sensor for resistance, however as stated in the manual when cold it should feed out 5,000, but it only fed out 2,000-3,000 and feeds out 230-250 ohms when hot (80c) when it should be 300 ohms. So the ect might be reason that code 6 is showing up. As for the vtec solenoid it's feeding out 15 ohms as stated and fed it 12 v from the battery, it clicks so the solenoid is good. I checked for continuity from ecu pin to solenoid that checked out. I'm lost as to what it could be. I think it might be a bad ecu ?

JdmKids Manny said:

So I've linked all of those wires to the thermostat housing for grounds. I've checked the ect sensor plug feeds out 5v, I've checked the ect sensor for resistance, however as stated in the manual when cold it should feed out 5,000, but it only fed out 2,000-3,000 and feeds out 230-250 ohms when hot (80c) when it should be 300 ohms. So the ect might be reason that code 6 is showing up. As for the vtec solenoid it's feeding out 15 ohms as stated and fed it 12 v from the battery, it clicks so the solenoid is good. I checked for continuity from ecu pin to solenoid that checked out. I'm lost as to what it could be. I think it might be a bad ecu ?

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Did you do them tests, in your house ? Of hand ,I think they need to be at room temperature for a accurate resistance test , don't quote me on that!
If you need pictures of anything in the car lot me know .

Ect sensor is 5 or 7 bob so I'd swap it out anyway,

Leej8 said:

Did you do them tests, in your house ? Of hand ,I think they need to be at room temperature for a accurate resistance test , don't quote me on that!
If you need pictures of anything in the car lot me know .

Click to expand...

Yeathe tests were done in a warm garage. I tried checking the circuit board on the ecu and I don't think I'm getting continuity from the board to the pin that enters the terminal on the harness plug. I also tried checking that sk5151 high side transistor switch that like to go bad, and only one leg out of the 5 legs it has provides a continuity signal. I have heard other ecu contain this transistor, even some non vtec one. Also I'm not getting 12v power after passing the vtec crossover which should happen. That is the transistors job.

I would like to tell you, your right , but iv no idea about that stuff , lol , gess be best to try a different ecu if you can?

Leej8 said:

I would like to tell you, your right , but iv no idea about that stuff , lol , gess be best to try a different ecu if you can?

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Yea, I'm just going to opt for an obd1 p28 chipped with a jumper harness. Too much of a hassle messing with a transistor and have everything not work properly.