What causes a vacuum tube to crack in an engine?
Exposed to extreme under-hood temperatures and oxygen in the atmosphere, rubber vacuum hoses and plastic vacuum tubes can become stiff or brittle, easily cracking or breaking. Similarly, rubber engine intake tubes can also become brittle, cracking and opening a way for unmetered air to get into the system.
What does ECM do in a vacuum leak?
Using the manifold absolute pressure (MAP) sensor or mass air flow (MAF) sensor, among others, the ECM modulates fuel injector pulse, spark timing, and valve timing. If there is a vacuum leak, the ECM may be unable to compensate.
How does the engine control module ( ECM ) work?
The engine control module (ECM) continuously monitors the environment in the engine. Using the manifold absolute pressure (MAP) sensor or mass air flow (MAF) sensor, among others, the ECM modulates fuel injector pulse, spark timing, and valve timing.
Can a vacuum leak cause a check engine light?
This could result in fuel trim problems and a check engine light, possibly with Fuel System Rich DTCs, such as P0172 or P0175. Some older power steering systems idle-up the engine using a vacuum switching valve (VSV), but a vacuum leak might stall the engine during a parking maneuver.
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.
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…
Why do I not feel pressure on my EGR valve?
You should feel vacuum or a slight pressure on your finger tip, depending on the particular system type. If you don’t feel a change in vacuum or pressure, likely the problem lies with the circuit that provides vacuum or pressure to the valve. Reconnect the vacuum hose to the valve.
What does the Check Engine light on EGR mean?
Check Engine Light comes on. Another symptom of a potential problem with the EGR vacuum modulator is an illuminated Check Engine Light. If the computer detects a problem with the EGR vacuum modulator signal or circuit it will set off the Check Engine Light to alert the driver of an issue.
What to do if your vacuum hose fails to ignite?
If it fails to ignite, contact a local ASE certified mechanic to inspect and repair the problem with the vacuum hose. If the vacuum hose needs replacement, allow them to complete this job and adjust ignition timing or fuel system adjustments if they are misaligned.