Replacement of Leaking VTEC Oil Pressure Switch on the 2003 Accord
Following the leak I had from the VTEC solenoid spool valve assembly which I aimed to repair by replacing the filter on the assembly (catch that DIY here), the leak continued. With the engine running and looking down at the VTEC spool valve assembly, I could just see the oil flowing slowly from the base of the VTEC oil pressure switch to the rear of the assembly.
My research online pointed to a worn VTEC oil pressure switch o-ring as the almost definite cause. I changed the o-ring in question, but the leak continued. I then felt this was because I used an aftermarket o-ring. I ordered for the OEM VTEC oil pressure switch o-ring from Honda and fitted that. That didn’t stop the leak either. With this, I turned my attention elsewhere. A quick feel of the junction between the metal and plastic parts of the VTEC oil pressure switch got oil on my finger. Voila!!! The leak was coming from this exact junction.
Enough of the history. Hope it helped. Its dirt time! For the purpose of making the procedure complete, I would address this DIY as though I hadn’t changed the o-ring for the switch earlier.
Materials: 22mm deep socket, ratchet with extension (30cm is more than adequate), 10mm socket or spanner, torque wrench (recommended, but won’t stop you from carrying out the repair if unavailable)
1. Detach the electric connector of the VTEC pressure switch and the 2nd electrical connector attached to the VTEC solenoid spool valve assembly.
2. Using the 22mm deep socket, extension bar and ratchet, break the seal on the pressure switch, but leave it in place. This would make it easier for you to loosen the part when you remove the whole assembly from the cylinder head.
NB: If you had recently replaced your VTEC oil pressure switch o-ring you can actually finish the procedure without bringing down the spool valve assembly. Simply take out the old part and continue with steps 7&9. If you are replacing the o-ring I advise bringing down the assembly to prevent dirt from getting into the groove for the pressure switch.
3. Remove the VTEC solenoid spool valve assembly from the cylinder head. All steps can be found in this earlier post
4. Remove the old VTEC oil pressure switch from the assembly.
5. Remove the old pressure switch o-ring from its groove and discard. If this is difficult to do by hand, use the curved tip of say a 1mm copper wire to remove the old o-ring.
6. Insert the new VTEC oil pressure switch o-ring in its groove.
7. Screw on the new part (PN: 37250-PNE-G01) by hand. I bought a used part from Mgbuka Obosi motor parts market. (Watch out for the post on buying good used parts!)
8. Refit the VTEC spool valve assembly onto the cylinder head (once again, steps are found in this previous post)
9. Torque the new VTEC oil pressure switch to 22Nm using the torque wrench and follow reverse steps.