bocas0225

I have a 2002 Honda Accord LX with a 2.3L ULEV VTEC motor w/ 5 speed manual transmission. The car is lowered 3" on 17in rims. I have been having issues with the PO112 Intake Air Temperature (IAT) sensor Low Input Circuit. I have replaced the IAT but I am still getting the same code. Im trying to get help with this situation. I am also getting a P1259 VTEC System Malfunction. When I looked up this code I found it to be a Bad VTEC Solenoid Spool Valve. So I went and bought a BRAND NEW VTEC Solenoid Spool Valve and put it on. I also read that if oil pressure gets low that it will also trigger the same code as well. I just changed my oil again last night and I am still having the same exact issue. Can anyone help me with this please!!!!

holmesnmanny

Have you looked at the IAT connector at all ? It could be badly corroded. If it looks good you're going to need to check for continuity back to the ecu connector/pin while wiggling the harness to see if there's an intermittent open.

For the 1259, it's possible the solenoid is bad. I've actually never heard of the switch ever actually being bad. Sometimes the solenoid will test fine but then people replace it anyhow and it fixes it.

bocas0225

Holmes in regards to the 1259 code I have already replaced the entire valve and solenoid. I'm still trying to figure it out but I'm having a hard time that's why I'm looking for help.... The IAT I replaced with a brand new one. I checked the wires as well but they are covered in black sheathing and I took it off and the wires are grounding out but I'm still looking at everything

holmesnmanny

For the 1259 check your oil pan and see if it's dented. If it is, it could be causing your oil pressure to be low.

Check the IAT connector like I said for any corrosion or for the inner pins to be deformed in.

Lost Again

What color are the two wires that are on the connector to the IAT? Yes I'm going somewhere, so answer the question please.

bocas0225

Lost Again... If I remember correctly i believe that one wire is black and the other wire is green with a white strip on it but I could be wrong. I will have to double check when I get home from work.

Lost Again

Please check because if those are the colors you have plugged into the IAT....they are wrong. Meaning you have a connector switched.

The GRN/BLK connector should be plugged into the PSP switch. Then I'll guess the one currently on the PSP has GRN/BLK and RED/YEL - that belongs to the IAT.

These connectors are pretty close to each other and have the same shape/size so if anyone was doing some pretty heavy work in that area could have switched the two.

bocas0225

Lost unfortunately I am not as familiar with abbreviations other then certain things I have recently learned. Can you please explain what you mean by PCP?? I also double checked the wires on the connection harness for the IAT and those wires are indeed Black and Green..... I was going to look up the wire diagram for the car so that hopefully I will be able to see if there is any way that way could be in the wrong position.... I was able to download a PDF file format of the Service Manual for the car tho and I added it too my Ipad and also to my Microsoft OneDrive so that was I will always have access to it no matter where I am.

tech8

The connector for the IAT sensor should have a Red/Yel wire and a Grn/Blk wire.

The connector for the Power Steering Pressure (PSP) Switch should have a Grn wire and a Blk wire. The PSP switch is on the power steering pressure hose, located under the left rear of the engine compartment.

bocas0225

Tech8.... Do you by chance have a diagram of how it should look?? The reason I ask is because the connection plug for my IAT which is directly on my Intake Manifold is a round plug with only 2 wires on it and those 2 wires are GRN & BLK.

tech8

Red/Yel and Grn/Blk does not refer to 4 wires, it refers to the 2 wires. A Red/Yel wire has red colored insulation and a yellow stripe running through, while a Grn/Blk wire has green colored insulation with a black stripe running through it.


If what you have plugged in is only a green wire and a black wire, then that is not the correct connector.

Lost Again

Not that I need to add much to what "tech" has posted.....that guy has more knowledge in his "pinky" than I will ever have.

I just want to add a pic of the connector and note the connector on the Intake Air Temp (IAT) sensor and the Power Steering Pressure (PSP) switch are both the same size and shape, the only difference is the wire colors on/in them.