How to Test and Replace a Busted Bimetallic Valve
The bimetallic valve is called as such because it's a disc or strip made of dissimilar metals. Because these metals expand and contract at different rates, the material can bend depending on the temperature. This action is perfect when it comes to allowing or preventing airflow to happen, thus ensuring vacuum regulation. Here's what you need to do to fix a potentially busted valve.
Difficulty Level: Moderate
What You'll Need
- Open-end wrench
- Socket wrench set
- Fuse holder
- 10-amp fuse
- 12-volt battery
- Jumper wires
- Vacuum hose
- Replacement bimetallic valve and solenoid
Step 1:First off, you should test your EGR solenoid and bimetallic valve to see if they're working properly. You also need to remove it first so that the test could be conducted. It comes with a nut and vacuum hoses attached to it that keeps it connected to your engine block.
Step 2: Detach the vacuum hoses and remove the electrical connector from the solenoid as well.Loosen up the nut that holds the valve to your engine block using a socket wrench. Afterwards, remove the solenoid from your engine compartment altogether.
Step 3:From there, make a jumper wire using an in-line fuse holder and install the fuse (10 amps). Connect both fuse holder ends to a section of wire with crimp connectors. Make another jumper wire then attach those wires to the valve solenoid's connectors.
Step 4: Beware of letting the wires touch, particularly the wires on the fuse ends and the other ends connected to the battery post's positive and negative terminals; this will make the fuse blow. As the solenoid is powered by the battery, it should click.
Step 5:Remove the jumper wires. Install the vacuum hoses on the vacuum ports located on the bimetallic valve. The solenoid controls the valve in order to regulate vacuum flow through the ports and the EGR.
Step 6:Blow into one of the hoses with sufficient force from your lungs. There shouldn't be any air passing through it. If air is passing through it, then the valve isn't closing properly and might require replacement.
Step 7:Attach your jumper wire to the battery once more to see if the solenoid clicks again. Blow through the vacuum hose again to see if any air passes. Air should pass through this time because the solenoid is energized.
Step 8:This test is for the sake of seeing if your valve or your solenoid is working properly. If the valve is opening when it's energized, it should allow unrestricted air flow. If the test shows a busted solenoid and valve, then it's time to replace either or both of them altogether.
Step 9: Here's what you need to do in order to replace your solenoid. Using an open-end wrench, disconnect the negative battery cable from your car's battery post. This should be done prior to your bimetallic valve EGR solenoid and valve replacement.
Step 10:Since you already have the bimetallic valve removed because of the test, just attach a new valve to your engine block with the nut you removed earlier then reconnect the electric wiring and vacuum hoses to your new replacement part.
The bimetallic valve regulates the vacuum pressure rate that's delivered to your car. It's attached with a nut to your engine block. It only takes a few minutes to replace a faulty bimetallic valve and you can save time and money by doing it yourself. It specifically controls how fast the air goes from your canister back to the throttle body.