omg B16 Idle Problem

[RonJ]

The ECT sensor on an OBD1 wire harness should have Red/Wht and Grn/Wht wires. I think you were testing the VTEC oil pressure switch. One possibility is that the VTEC oil pressure switch and ECT sensor connectors are swapped. Check for that.

Also post a picture of the sensor that you tested.

The ECT sensor (TW sensor) for a D16Z6 engine is shown below:

 

[1991civicb16]

The ECT sensor on an OBD1 wire harness should have Red/Wht and Grn/Wht wires. I think you were testing the VTEC oil pressure switch. One possibility is that the VTEC oil pressure switch and ECT sensor connectors are swapped. Check for that.

Also post a picture of the sensor that you tested.

The ECT sensor (TW sensor) for a D16Z6 engine is shown below:

Nope i didnt test the right one lol.... ok going back to the garage...

 

[1991civicb16]

This is the one i just tested it has the red wire like you said the green connector is the one i did last time. So the reading this time for it was 173 and it would gradually go down a digit the longer i waited.

 

[RonJ]

Was the engine fully warmed up? Was the sensor unplugged and was resistance measured across the two sensor terminals? Is there oil inside the connector?

Depending on your answers, there are additional ECT sensor tests.

 

[1991civicb16]

Was the engine fully warmed up? Was the sensor unplugged and was resistance measured across the two sensor terminals? Is there oil inside the connector?

Yes engine was fully warm i let is sit for like 30 mins didnt see any oil in the connection. when i unplugged it the motor reved up higher and cel turned on. I can wait longer the gauge only goes like 1/4 of the way up and the heater is blowing really hot air...

 

[RonJ]

Next tests:

Unplug the ECT connector and then make these two voltage measurements with the key in ON(II):

1) Between the Red/Wht (+) and Grn/Wht (-) wire terminals in the connector

2) Between the Red/Wht (+) wire terminal in the connector and body ground (-)

 

[1991civicb16]

Next tests:

Unplug the ECT connector and then make these two voltage measurements with the key in ON(II):

1) Between the Red/Wht (+) and Grn/Wht (-) wire terminals in the connector

2) Between the Red/Wht (+) wire terminal in the connector and body ground (-)

Terminals were 4.97 and from body was 5.00

 

[RonJ]

Voltages are good. The ECT sensor resistance is somewhat below spec, but I'm not convinced that would cause the problem.

I think a few electrical tests on the IACV are now warranted.

1) Unplug the IACV and measure resistance across its two terminals (IACV not IACV connector).

2) In the free connector with the key in ON(II), measure voltage to body ground at the Yel/Blk wire terminal.

 

[1991civicb16]

Voltages are good. The ECT sensor resistance is somewhat below spec, but I'm not convinced that would cause the problem.

I think a few electrical tests on the IACV are now warranted.

1) Unplug the IACV and measure resistance across its two terminals (IACV not IACV connector).

2) In the free connector with the key in ON(II), measure voltage to body ground at the Yel/Blk wire terminal.

Alrighty... off to that part again.... so you want ohms reading on the IACV itself and voltage for the connector. I will post in about 10 mins

 

[RonJ]

Alrighty... off to that part again.... so you want ohms reading on the IACV itself and voltage for the connector. I will post in about 10 mins

Yes sir.

 

[1991civicb16]

Ok im back the connector measures 10.75 without ground to body. With body ground 11.84
The sensor reads 310 and lowers by a digit.

 

[RonJ]

Ok im back the connector measures 10.75 without ground to body. With body ground 11.84

How did you do these two tests?

The sensor reads 310 and lowers by a digit.

310 Ohms across the two terminals of the IACV itself? To my knowledge, that's way too high. It should be about 8-15 Ohms.

And what B16 engine do you have? Is the IM and TB also from a B16?

 

[1991civicb16]

How did you do these two tests?



310 Ohms across the two terminals of the IACV itself? To my knowledge, that's way too high. It should be about 8-15 Ohms.

And what B16 engine do you have? Is the IM and TB also from a B16?

For the two tests i set the multi to volts 20 i think then i touched the inside of the connector were the black wire goes in with the red prong and the black one in the blue i think it was then i put the black prong on a ground bolt.

Yes its the JDM b16a 88-91 Throttle body and IM.

 

[RonJ]

For the two tests i set the multi to volts 20 i think then i touched the inside of the connector were the black wire goes in with the red prong and the black one in the blue i think it was then i put the black prong on a ground bolt.

Yes its the JDM b16 Throttle body and IM.

The voltage seems fine, but doesn't the IACV have Yel/Blk and Grn/Wht wires?

Just to make sure, you should repeat the resistance test. Do you know anyone with a compatible IACV? Maybe they would let you swap it in for test?

 

[1991civicb16]

The voltage seems fine, but doesn't the IACV have Yel/Blk and Grn/Wht wires?

Just to make sure, you should repeat the resistance test. Do you know anyone with a compatible IACV? Maybe they would let you swap it in for test?

Not mine its blue/white and black/white and i just went outside before i typed this to double check the readings and its the same as i posted. As for another IACV i got a 91 accord would it have one? Im the only person i know with a honda period lol

 

[RonJ]

Not mine its blue/white and black/white

Might they be Blu/Yel and Blk/Yel?

What color are the two wires on one of the fuel injectors?

Check the resistance across the two terminals of the 91 Accord IACV. Do you think it would fit on your Civic?

 

[1991civicb16]

My bad typo not 310 it's 3.10
its blue yel/black yel then its dark i just know ones blue ones black for sure.

 

[RonJ]

My bad typo not 310 it's 3.10
its blue yel/black yel then its dark i just know ones blue ones black for sure.

3.1 Ohms is still out of spec for the IACV. It should be 8-15 Ohms. Make the same measurement on the Accord IACV.

Those are OBD0 IACV wire colors, not OBD1.

 

[1991civicb16]

3.1 Ohms is still out of spec for the IACV. It should be 8-15 Ohms. Make the same measurement on the Accord IACV.

Grrr ok... bangin my hands up lol for these readings. I will be back

 

[1991civicb16]

OK well i tested the accord it read 23 ohms.
I think they used the OBD0 harness and used the ODB1 jumper harness to use an OBD1 computer.