Plain English
What P0455 means for your Jeep Grand Cherokee
Jeeps use a Natural Vacuum Leak Detection (NVLD, also called LDP - Leak Detection Pump) system instead of the simpler EVAP designs from Honda/Toyota. The NVLD pump on the charcoal canister is a known weak point. P0455 on a Grand Cherokee usually means: gas cap, NVLD pump, or a cracked EVAP hose. NVLD pump failures are by far the most common Mopar P0455 cause - the pump itself is $80-$150.
🎯 Top Causes on the Jeep Grand Cherokee
40%
#1 CAUSE
NVLD / Leak Detection Pump Failure
The NVLD pump (also called Leak Detection Pump or LDP) on the canister is a Mopar-specific module that pressurizes the EVAP system to test for leaks. The pump's check valve fails, the diaphragm tears, or the solenoid sticks - any of which throws P0455. Diagnostic test: with the key on engine off, you should hear the NVLD pump cycle. If silent, the pump is dead.
NVLD Pump
$80-$180
w/Labor
$160-$320
DIY Time
30-60 min
35%
#2 CAUSE
Worn Gas Cap
Mopar gas caps wear at 80k-130k miles. Tighten to 3 clicks. Replace with Mopar OEM cap.
Tighten
Free
Mopar Cap
$15-$30
Aftermarket
$8-$18
15%
#3 CAUSE
Cracked EVAP Hose
Hoses along the chassis crack at 8+ years. Off-road Grand Cherokees are more prone - underside damage from rocks. Smoke-test or visual inspection.
Hose Repair
$15-$50
Smoke Test
$80-$140
w/Labor
$60-$220
10%
#4 CAUSE
Charcoal Canister Damage
Mounted near the rear axle. Off-road impact damage or aged plastic cracking. Inspect for cracks and fuel smell.
Canister
$120-$280
w/Labor
$220-$500
DIY Time
60-90 min
🚗 Most Affected Grand Cherokee Model Years
| Year | Engine | Primary Cause | Typical Mileage | Notes |
|---|---|---|---|---|
| 2011-2017 | 3.6L Pentastar | NVLD + gas cap | 70k-150k | NVLD failures very common |
| 2011-2017 | 5.7L Hemi | NVLD + gas cap | 80k-160k | Same EVAP system |
| 2018-2022 | Various | Gas cap + NVLD | 40k-100k | Updated NVLD - fewer reports |
🔧 How to Diagnose P0455 on a Jeep Grand Cherokee
- Tighten gas cap to 3 clicks. Free first step.
- Listen for NVLD cycle. Key on, engine off - you should hear a faint clicking from the rear (NVLD pump cycling). If silent, the pump is dead.
- Replace NVLD pump if dead. Mounted on the canister, accessible from under the rear.
- Smoke-test for hose leaks. $80-$140.
Want a step-by-step walkthrough specific to your Jeep Grand Cherokee? Run a $5.99 AI diagnosis report - we narrow the cause to your year, engine, and symptoms.