93CX

Hello HT - this is my first thread for years. I've done a ton of research, but still have not found a solution to my CEL #4 for CKP sensor.

My car:
1993 Honda Civic Cx
Built B16A from HMO

Last year I had my JDM B16A built with CP pistons, eagle rods, etc. I have put about 500 miles on the new engine so far. In November of last year, it started running really rough out of the blue one day and had a hard time idling, it wanted to stall. I got a check engine light, CEL #4. I shut the car down for the winter that day.

Fast forward to today, I purchased a new distributor and tried swapping it out. No luck, the car still runs rough and sounds terrible as well. I double checked the spark plug wiring, and it is installed correctly. I tried a second set of plug wires, and no change. The car feels like it may be in limp mode.

Cliff notes: CEL for #4 CKP. Reset ECU. Changed distributor. Changed plug wires. No difference.

Can anyone suggest what I could try next? TIA.

apexi_rsx

sounds like ur getting a misfire of some sort causing this code... id do a compression test on the motor. sounds like u have engine failure...I hope u have receipts and someone will warranty their work for you...

Former User

Code 4 still thrown after resetting ECU?

93CX

If you mean resetting the ECU by unhooking battery for 10 mins, then yes. Unfortunately I did not get a warranty for the block.

Former User

Ohm test (open and short) the CKP wires and sensor. If they're fine, then the ECU may be bad.

93CX

I got 375-400 Ohms from the new distributor using the resistance test section of this guide:

http://www.ozhonda.com/forum/showthr...ics-Code-4-CKP

That appears to be within spec. Should I try wiring the CKP wires directly to the ECU?

Former User

You tested the CKP sensor's resistance. Now Ohm test the CKP wires for a short or open from the ECU connector.

1. Turn key off and disconnect the battery.
2. Disconnect ECU connector B.
3. Measure resistance between pins B15 and B16 in the connector. Post the Ohm reading.
4. At pin B15 and b16 in the connector individually measure continuity to body ground. Is there continuity?

If you have any questions about the tests, post them.

http://www.phearable.net/images/tech...schematics.gif

.

93CX

Resistance between pins B15 and B16 at 20K Ohms setting = 9.04

I have never tested continuity before.
Pin B15 to ground stays at a reading of 1 and does not move.
Pin B16 to ground stays at a reading of 1 and does not move.
I'm not sure that I did this part right. What setting on my multimeter should I use? This is what I am working with:




Thanks a lot for your help.

93CX

Just to clarify, to test continuity I probed a chassis ground with the black wire, and probed pin B15 and B16 on the ECU with the red wire (in the left hand Ohms socket on the multimeter).

I tried 200, 2k, 20k, 200k, etc, and it would only read "1". When I touched the two probes together, I got 0.00.

Former User

Redo measurement with meter dialed to the 200 Ohm scale. Plug the meter probes into the 2 holes on the left side of the meter.

Is the continuity setting just to the right of the 200 Ohm scale?

Check the meter's owner's manual to see if it has a continuity setting. If not, you can use the 200 Ohm scale and then touch one meter probe to one of the pins and the other meter probe to the metal frame under the dash. Then post the Ohm reading.

Former User

Good, except with the meter set to read continuity or Ohms (200 Ohm scale), touch one meter probe to pin B15 or B16 in the unplugged connector, not the ECU side.

93CX

Thank you for the very detailed instructions. I do not get a reading when performing the tests you described. The multimeter stays at "1" and does not move on the 200 Ohms setting. I tried other Ohm settings with the same result. What does this mean?

93CX

Tonight I tried stripping down some of the wire directly before the ECU connector B and probed that with the multimeter, in case I was not getting a good connection when probing inside the plastic plug itself. I still did not get any reading when measuring resistance between B15 and B16, nor do I get a reading when probing B15 and ground, or B16 and ground. Can anyone tell me how to proceed from here? Thanks in advance.

carlos8

If you get the ohms within specs in the distributor plug, but still get the CEL 4.

Then check continuity in b15 and b16 from distributor harness plug to ECU plug, one of this wires maybe is open.

For the test ronJ is telling, you can use the voltmeter set to resistance or 2000 for this test. If you use the 200 ohm scale you get 1.