P2498: EGR Cooler Bypass Position Sensor Range/Performance (Bank 2)

With P2498 the bank 2 bypass position signal is electrically valid but not believable, for example because it does not change when the flap is commanded, settles at an unexpected value or no longer matches the end stops learned earlier. There is no public manufacturer description for this bank 2 code. The closest documented case is bank 1: GM's 2015 LML Duramax showed P2493 together with other bypass sensor codes, and GM's answer was a complete new bypass valve, because sensor and valve form one unit. On a twin-cooler engine the same reasoning applies to the second bank, so a sensor fault and a mechanically binding flap must be told apart with live data before parts are ordered. The bank 1 version is P2493; the actuator side of bank 2 is P248F.

Bank 2 is the side without cylinder 1, so it only exists on V or boxer engines.

Symptoms

• Check engine light on
• Measured and commanded bypass position differ on bank 2

Most likely causes

• Worn bank 2 bypass valve with built-in sensor
• Flap binding so the sensor reads a position other than commanded
• End-stop learn values invalid after a repair

What to check, in order

Start with the simplest. You can tick off each step.

1. Check the connector and any vacuum hoses
2. Compare the reading with other engine data while varying the engine speed.
3. Use live data to compare the commanded opening with the actual opening
4. Clean the valve and passages if they are clogged with carbon
5. Test the actuator with the scanner
6. Replace the valve if it still does not follow the command after cleaning

Good to know

• Repair difficulty: medium
• It affects emissions.

What each character of P2498 means

• P: Powertrain: engine and transmission
• 2: Generic code: same on every make
• 4: Emissions
• 98: Specific fault in that system

Frequently asked questions

Can I keep driving with code P2498?

You can normally drive in moderation, but get it repaired soon: if the valve is stuck open, the engine may idle very poorly.

What causes code P2498?

The most common causes are: worn bank 2 bypass valve with built-in sensor; flap binding so the sensor reads a position other than commanded; end-stop learn values invalid after a repair.

Related codes

• P2493EGR Cooler Bypass Position Sensor Range/Performance (Bank 1)
• P2497EGR Cooler Bypass Position Sensor Circuit (Bank 2)
• P2499EGR Cooler Bypass Position Sensor Circuit Low (Bank 2)
• P249AEGR Cooler Bypass Position Sensor Circuit High (Bank 2)
• P248FEGR Cooler Bypass Control Circuit Range/Performance (Bank 2)

Sources

• law.cornell.edu: 13 CCR 1968.2
• static.nhtsa.gov: MC 10113767 9999

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.