P0352 after plug and wire change

[Jinx3Mt]

So I'm new to this forum and have seen a lot of people with a P0352 code. The 2 main fixes seem to be to R&R the coil packs and if that doesn't work possible the PCM.

This is a long post but so I'll get to it. I have 95 with a 2.3L, manual trans, and 4 wheel drive that was given to me. I did not have the P0352 code at this point but my fuel economy was crap so I cleaned the MAF and the Pressure sensor that is in front of the throttle body. Since both of those components were very dirty I decided to check the plugs and wires.

The wires came apart while removing them, and all but on plug had normal but severe wear. The odd ball had a ton of corosion at the connector. I had also had an emission code that ended up being rotted vacuum hose at the purge valve. I wasn't very confident about drivers side cyl 3 and 4 plug wire connections but it seemed to run fine. The next morning I had a P0352 immediately after starting the engine.

My main question is can a bad plug wire connection cause the P0352 or is this code only from the coil and PCM. If you say it's the coil or PCM please provide pinpoint tests so I can verify which is bad. I checked resistance on the secondary circuit of the front coil that controls the intake side and it was within spec.

I am not a parts changer unless I can verify the issue before replacement. If possible please help me out with this. If more info is required let me know. Thanks in advance.

P.S. told you it was a long post.

 

[Trippy]

Welcome to TRS,

I checked resistance on the secondary circuit of the front coil that controls the intake side and it was within spec.

Did you test exhaust side coil? The exhaust side is the primary spark system on our setup.

If you suspect the spark plug wire you can always test it https://www.instructables.com/id/How-to-Test-a-Spark-Plug-Wire/

Coil Test: https://www.autozone.com/repairguides/Mazda-Trucks-1994-1998-Repair-Guide/DISTRIBUTORLESS-IGNITION-SYSTEM/Ignition-Coil-Pack-s/_/P-0900c1528008ce2a

You can also check for spark using this method.

1. Remove the spark plug.
2. Connect the spark plug to the spark plug wire.
3. Hold the spark plug with insulated pliers 0.20-0.40 in (5-10 mm) from a ground.
4. Crank the engine and verify that there is a strong blue spark.

The reason for testing the other coil would be to swap coils to see if the problem moves with the coil.

 

[Jinx3Mt]

Thank you for the reply. I did not check the exhaust side coil I will though. Because of how difficult it was to get the wires on to intake side 3 and 4 plugs I would like to know if the wire is not fully seated on the plug could it cause the P0352 code? Or would it just set a different misfire code?

 

[Jinx3Mt]

Tested rear (Exhaust) coil pack. Got .7 on each primary. Secondary I got 14.78 on one side, and 14.62 on the other side. The secondary is within the 13 to 15 k tolerance.

For the front (Intake) coil pack I got the exact same primary reading but on the secondary 14.36 and 14.31. Still within speck. Wondering if I should replace the rear one because of the difference between the two. I think a new on was around 14.3ish just like the front pack. Thoughts?

 

[Trippy]

If they are within the specification I would not replace them. I would check to see if the PCM is actually firing them by doing a spark test.

If you have one of the old spark plugs and a spark plug wire you can test to see if spark is actually being sent to the plug. Take precautions so you don't get shocked by the spark.

If it fires then you know that the problem might be related to your new wires or plugs (poor connection or faulty spark plug wires). If spark is not being sent then you know your problem lies in wiring or PCM. Since the DTC was not present before, I feel like it might be related to the new parts.

Are there any other DTC's?

 

[Jinx3Mt]

So because of the difference between the two coil packs I replaced the rear (passenger side) coil pack. So father chose has not returned. I'll see what happens in the morning when I leave for work.

 

[Jinx3Mt]

Damn auto correct

 

[Jinx3Mt]

Replacing the rear (exhaust side) coil pack did the trick. Thank you for the input.