How do you test an EGR vacuum modulator?
(a) Disconnect the vacuum hoses from ports P, Q and R of the EGR vacuum modulator. (b) Block ports P and R with your finger. (c) Bllow air into port Q, and check that the air passes through to the air filter freely.
What happens when you unplug your EGR?
If you unplug it, while the truck is off, then the EGR will stay closed. If the EGR valve is clogged or completely blocked off it can longer re-burn harmful emissions in the combustion chamber.
What are the symptoms of a bad modulator?
Some of the most common signs of a bad transmission control module are as follows:
- Slow Acceleration: It takes longer than normal for your vehicle to pick up speed.
- Gear Slippage: Your transmission switches gears without warning or without you shifting.
- Inability to Shift: You can’t shift out of neutral.
How does the vacuum modulator work on an EGR system?
The EGR vacuum modulator is a component found on some EGR systems. It controls the flow of the EGR system by using a vacuum operated diaphragm to increase or decrease EGR flow. When the vacuum is high, combustion temperatures and airflow are naturally lower so the diaphragm will close…
How to test an EGR valve, a simple procedure?
Connect a hand vacuum pump to the EGR valve in place of the vacuum hose and apply 15 in-Hg of vacuum to the valve (if you don’t have access to a vacuum pump you may borrow-rent one from a local auto parts store). As you apply vacuum to the valve, check for diaphragm movement.
Why is my EGR valve not working properly?
If there is a fault in the EGR system, it can cause the EGR not to function properly. Your vehicle’s EGR valve can be faulty due to the accumulation of carbon deposits in its internal surface, pitting, burnt valve, a damaged diaphragm for a vacuum-type EGR valve, or distortion of the valve seat. This problem can also have the following causes:
How can you tell when your modulator valve is bad?
Check the exhaust of the car for blue-colored smoke. When the diaphragm inside the modulator valve ruptures, transmission fluid is drawn up to the engine like liquid through a straw via the steel vacuum tubing.