I recently bought a 2001 accord 4cyl with a p1259 issue. I recently fixed a rear main seal leak, which lead me to believe that low oil amounts were triggering this code at first. One day before I fixed the rear main seal, I filled the oil with 5w20 mobil oil and the engine light turned off once I got on the highway but then turned right back on the next car ride maybe since the oil leaked out so fast. So I fixed the leak and then accidentally bought 5w30 oil to refill it with. I drove the car around temporarily by undoing the negative battery contact and the light would stay off for a while and then come back on and throw it into limp mode. I tried removing and cleaning the solenoid and this did not work and I even replaced the solenoid and this still did not work. The solenoid was for a 1995 model but it looks exactly the same and it included the vtec pressure sensor. I was under the car one day and noticed the knock sensor was broken in half and I also replaced that, and ever since then that day I cant even drive down the street before the light comes on. When I connected the sensor I heard the click and everything so it seems to be on properly. When I drive the car its constantly in limp mode. The idle isnt smooth and the rpm will shoot up if you step on the gas. there are also rough transmission shifts. The acceleration is so poor that its embarrassing to drive on any busy road. Its also way worse when I drive over a hill. Gas mileage is also poor. When I first start the car it will seem fine but once it heats up it will start running like crap. The rpm sometimes shakes up and down too which also makes the car shake back and forth. Im just so frustrated with this problem and I just really dont know what else to do to solve this. Im thinking maybe the wrong oil viscosity is throwing off the oil pressure.

 

Have you tried cleaning out/replacing the gasket/screen between the VTEC solenoid and the cylinder head? It is another common issue that can cause a P1259 (DTC 22) fault.

As far as the running condition of the car, sounds like you may have some loose valve clearances or an EGR system that is stuck open. And then the surging idle is usually an indication of a vacuum leak somewhere on the intake manifold.

Have you performed any other regular maintenance on the car? Plugs, wires, distributor cap, valve adjustment etc etc....

Have you since tried to read the "limp mode" codes stored on the ECU, still P1259? or are there any others?

 

I replaced spark plugs and I'm going to take it to advance auto soon to check for other codes

 

Also the car smells like exhaust when I turn it on

 

If you replaced the solenoid already and it's still throwing the code it's likely a wire issue. You should check for continuity from the pressure switch and the solenoid back to the ecu connectors at their respective pins after disconnecting the connectors from the ecu after accessing the ecu.

Also, take a good look at the connectors for the solenoid and the pressure switch. See if they look corroded, out of place, or the wires appears to be loose or broken that go to them.

http://technet.ff-squad.com/wiring.obd2b.htm

 

It says the obd2 wiring is for the civic is this the same for the accord ??

 

The Accord's ECM/PCM's wiring is not the same as a Civic.

 

I didnt say to rewire the car. Its 3 pins you need to check. If somehow thats not correct do some searches.