View source for EGR tube

'''EGR tube''' refers to the exhaust gas recirculation tube used on the [[Pontiac Fiero]] [[EGR system]].

The EGR tube carries exhaust gas from the exhaust side of the engine to the intake side so that exhaust gas can be recirculated under certain operating conditions.

== Overview ==

The EGR tube is part of the exhaust gas recirculation system.

On the Fiero, the EGR tube is especially important on the 2.8L V6 because cracks or leaks in the tube can create vacuum-leak symptoms and drivability problems.

A cracked EGR tube can allow unmetered air into the intake, causing high idle, lean running, hesitation, poor drivability, or diagnostic trouble codes.

== Location ==

{{Image wanted|Photo or diagram showing the EGR tube location on the 2.8L V6 Fiero, including its connection between the EGR valve/exhaust side and the intake plenum. A 2.5L four-cylinder example would also be useful if applicable.}}

On the 2.8L V6, the EGR tube runs between the [[EGR valve]] area and the intake plenum.

It is located in the engine compartment near the upper intake and EGR valve. Because of heat, age, and vibration, the tube can become brittle or crack over time.

The exact EGR tube layout on the 2.5L four-cylinder may vary by year and engine configuration.

== Function ==

When EGR operation is commanded, exhaust gas passes through the EGR tube and enters the intake system.

This allows a controlled amount of exhaust gas to mix with the incoming air charge. The purpose is to reduce combustion temperature and emissions under certain operating conditions.

== Relationship to vacuum leaks ==

On the 2.8L V6, a cracked EGR tube can act like a vacuum leak.

This can cause symptoms such as:

* High idle
* Rough idle
* Lean running
* Hesitation
* Surging
* Poor drivability
* [[Code 44]]
* [[Code 35]]

Because the EGR tube is close to hot exhaust components, cracks may be difficult to see without careful inspection.

== Related trouble codes ==

EGR-tube-related problems may contribute to:

* [[Code 32]] - EGR system
* [[Code 35]] - Idle speed error
* [[Code 44]] - Lean exhaust indication

== Code 32 ==

[[Code 32]] indicates that the ECM has detected a problem with EGR vacuum control or EGR system operation.

An EGR tube problem may be part of the diagnosis, especially if the tube is cracked, leaking, restricted, or incorrectly installed.

== Symptoms ==

Possible symptoms of an EGR tube problem include:

* High idle
* Rough idle
* Hesitation
* Lean-running symptoms
* Check engine light
* Vacuum leak symptoms
* Poor drivability
* Failed emissions test
* Exhaust leak symptoms in some cases

== Diagnosis ==

Basic diagnostic checks include:

# Inspect the EGR tube visually.
# Look for cracks, splits, loose fittings, or missing fasteners.
# Check for signs of exhaust leakage.
# Check for vacuum-leak symptoms.
# Inspect nearby vacuum lines.
# Check the [[EGR valve]] and [[EGR solenoid]].
# Check for stored diagnostic trouble codes.
# Check for high idle, lean codes, or idle speed errors.
# Replace or repair the tube if it is cracked or leaking.

== Common inspection issues ==

EGR tube cracks can be hard to find because the tube may be hidden by heat shielding, intake parts, or its installed position.

Possible inspection methods include:

* Visual inspection with a light and mirror
* Listening for leaks
* Smoke testing the intake system
* Carefully moving heat shielding if present
* Inspecting around both tube ends
* Looking for soot, cracks, or loose mounting points

== Replacement notes ==

Replacement EGR tubes should fit correctly and seal properly at both ends.

When replacing the tube:

* Use correct gaskets if required.
* Avoid forcing the tube into place.
* Check mounting surfaces.
* Tighten fasteners evenly.
* Recheck for leaks after installation.
* Inspect related vacuum lines and EGR components at the same time.

== Notes ==

A cracked EGR tube can mimic other problems, especially vacuum leaks and idle-control faults.

Before replacing sensors or the idle air control valve for high idle or lean symptoms, the EGR tube should be inspected on V6 Fieros.

== See also ==

* [[EGR system]]
* [[EGR valve]]
* [[EGR solenoid]]
* [[Vacuum leaks]]
* [[Idle problems]]
* [[Code 32]]
* [[Code 35]]
* [[Code 44]]
* [[Diagnostic trouble codes]]

[[Category:Fieropedia]]
[[Category:Diagnostics]]
[[Category:Engine]]
[[Category:Emissions]]