2021–2025 Durango or Grand Cherokee Extended Crank? Time the Fuel-Pressure Drop

Long Crank? Watch Pressure Decay

An extended crank after a Durango or Grand Cherokee has been sitting is a timing problem before it is a parts problem. How long did it sit, what was fuel pressure at key-off, and how far did pressure fall before the next start? Stellantis TSB 14-004-25 Rev. B makes one branch exact: a fuel-pressure and system leak-down loss greater than 10 psi sends a covered vehicle toward the fuel-pressure-regulator procedure; a smaller loss closes this bulletin.

A fuel-pressure kit can turn the wait into a pressure-versus-time record when the low-pressure connection and adapter are confirmed. The AUTOOL PT635 fuel pressure gauge is one option for a compatible circuit. It cannot connect to a GDI high-pressure rail, identify whether decay passes through a regulator, injector, pump check valve, or external leak, or make fuel exposure safe.

The useful chart has only two axes—pressure and elapsed time—but every test condition beside it must remain fixed.

Start the clock before the next key cycle

Ask the driver to describe the event without suggesting a regulator: first start of the day, warm restart, after refueling, one hour parked, or several days parked. Record crank duration, cranking speed, outside temperature, fuel level, fuel odor, prior key cycles, whether key-on priming changes the start, and any DTCs or freeze frame.

Do not repeatedly cycle the ignition before pressure is connected. Each pump command can rebuild residual pressure and erase the very failure being investigated. Stop if liquid fuel or a strong leak is present, and keep flames, heaters, cigarettes, sparks, and non-rated equipment away.

Confirm the engine and build fence

The revised bulletin covers certain 2021–2025 Dodge Durango WD and 2021–2022 Jeep Grand Cherokee WK vehicles in North America, with specified 3.6L ERC or 5.7L EZH engines and a Durango build limit. Confirm VIN, model code, engine sales code, build date, software, and current Service Library before carrying the 10 psi rule into the bay.

Model name and symptom alone are insufficient. A newer Grand Cherokee platform, a different engine, or an out-of-market vehicle may use a different supply architecture and diagnostic threshold. The bulletin is technical information, not automatic repair authorization or recall coverage.

Clear cranking speed before fuel conclusions

Low cranking voltage and slow rpm can produce a long start even when residual fuel pressure is normal. Inspect battery label and terminals, save the arrival voltage, and test the battery and starting circuit under the appropriate procedure. Compare cranking rpm and voltage during a normal and failed start if data is available.

Also save immobilizer, crank/cam synchronization, coolant-temperature plausibility, throttle, and fuel-command clues. A no-synchronization event, flooded condition, vapor issue, weak ignition, or software concern should not be squeezed into a leak-down test simply because the starter runs longer.

Connect only to the approved low-pressure point

Relieve pressure and connect at the service point named by current Stellantis information, using a hose and adapter rated for the fuel, pressure, and temperature. Secure every coupling, route the hose away from exhaust and rotating parts, and perform a leak check before starting. Catch and dispose of fuel safely.

Do not attach a conventional low-pressure gauge to a high-pressure direct-injection rail. The published upper range of an instrument does not prove that its hoses, adapters, connection, or operator are appropriate for that circuit. A professional should control this work in a ventilated bay with fire protection.

Record pressure as a timed decay

Follow the exact running or priming condition, stabilize pressure, and mark time zero at the same key-off event each time. Record pressure at fixed intervals rather than watching for a vague movement. Note battery voltage, fuel temperature/level, ambient temperature, and whether any key, door, or scan command reactivated the pump.

Time from key-off	Pressure	Pump reactivated?	Visible/odor check
0	record	no	dry/no vapor odor
service interval 1	record	no	repeat
service interval 2	record	no	repeat
final specified time	record	no	calculate total drop

The correct interval comes from the current procedure. A graph without a known start state or with an unnoticed prime event is not a leak-down result.

Read the greater-than-10-psi branch narrowly

TSB 14-004-25 Rev. B asks whether fuel pressure and system leak-down dropped more than 10 psi. A result above that boundary opens Step 3, the regulator replacement procedure, for a vehicle already inside the bulletin fence. A result that does not exceed it completes this bulletin and returns the unresolved complaint to normal diagnosis.

Do not round a noisy or low-resolution reading toward the repair. Repeat borderline tests with a verified gauge, stable connection, and identical time interval. Record absolute starting pressure as well as drop; a 10 psi change from an invalid starting state is still invalid.

Keep regulator diagnosis from swallowing other leak paths

Pressure decay describes loss of stored hydraulic energy. Outside the bulletin-directed repair, possible paths can include the pump module check function, a regulator, injector leakage, a connection, or an external leak. The gauge does not show which way fuel moved.

Fuel odor, rich restart, cylinder wetness, oil dilution, or external dampness changes the safety and diagnostic branch. Injector or high-pressure testing requires the correct equipment and process. Do not clamp molded lines, energize a pump with arbitrary power, or use compressed air to hunt the path.

Verify after the same soak interval

After the approved repair, restore all fuel connections, retainers, shields, and electrical connectors. Leak-check first, then repeat the original pressure/time graph with the same fuel level, key sequence, and soak duration as closely as practical. Save the post-repair first-start crank time and cranking voltage.

The case closes when no fuel escapes, the pressure decay meets current criteria, the engine starts normally after the previously troublesome interval, and relevant codes do not return. An immediate start five minutes after repair is not equivalent to an overnight complaint.

Official references

• Stellantis TSB 14-004-25 Rev. B: extended crank due to fuel-pressure loss
• Mopar VIN recall lookup