Ford P1335: EGR position stops and diagnosis before replacement

Searching online for P1335 can produce different descriptions. The first step is not to choose the most repeated one, but to verify the make, engine and applicable scan description. This guide addresses the Ford EGR meaning; it does not define the code for every manufacturer.

The accompanying case concerns a Transit 2.2 TDCi with P1335, P1303 and P042F and severe power loss. The fact that a new EGR resolved that van's problem is a real result, but it is not enough to decide what another vehicle with the same code needs.

Ford's OBD-II list associates P1335 with EGR position sensor A performance at the minimum or maximum stops. Ford's 6.4 L diesel monitoring documentation refers specifically to the minimum stop. Both place the issue in position-reference control. F1: 2012 OBD-II Codes F2: 2008 MY OBD System Operation Summary for 6.4L Diesel Engine

It should not be reduced to “EGR fault at idle.” An end-stop position and an engine operating speed are different concepts. To establish which end and operating conditions your engine monitors, use its service procedure rather than another Ford's values.

The 6.4 L information explains the concept here; it does not establish voltage, percentage or tolerance specifications for a Transit 2.2 TDCi. Nor does this guide identify the Transit's year or assume every version uses the same EGR.

Think of a mechanism whose controller must recognize where its travel begins and ends. Knowing that it moved is not the same as knowing that it reached a valid reference. This helps explain why a system can register a position fault even when the actuator responds to some extent.

In an EGR system with feedback, the controller uses position information to manage the assembly. Ford documents checks on that reference in the cited monitor. If the information does not match what is expected, both the movement and how it is detected need investigation. F2: 2008 MY OBD System Operation Summary for 6.4L Diesel Engine

This does not prove a failed sensor. Feedback may be inconsistent because the mechanism cannot reach its expected position, because the circuit distorts the reading, or because an application-specific adjustment needs to be checked.

An EGR reading on a scan tool can help, but first establish what it represents. Is it commanded position, measured position, actuator command or a learned value? Two parameters using the % symbol need not describe the same thing.

Do not assume closure always appears as 0% on every tool. This guide defines no universal scale. Compare corresponding data and do so under the manufacturer's specified conditions.

If a reading changes, the next question is not merely “does it move?” but “does it reach the expected reference, and is that response coherent?” Visible movement or the sound of actuation alone does not answer that second question.

Save all codes and descriptions before clearing anything. Note when the problem appeared and whether replacement, cleaning or disconnection occurred recently. Initial data help distinguish an existing fault from something introduced after work.

Confirm the engine, installed part and applicable service information. Do not apply another version's terminal assignments or measurements simply because it is also called Transit. The commercial name does not replace the technical identification needed for testing.

Start with the connector, terminals and accessible wiring. Look for corrosion, incomplete connections, chafing or previous repairs. Using the correct diagram, test the power, ground and signal circuits actually used by the assembly. F3: Exhaust gas recirculation – EGR valve

Do not apply power directly to unknown pins to “see whether it moves.” An inappropriate test may damage the component or its controller. Without a wiring diagram and compatible equipment, stop that test rather than invent a reference value.

The aim is to separate a reading altered by the installation from a component problem. If the circuit has not been checked, replacing the sensor or entire EGR can leave the original cause untouched.

When the tool and system support actuation testing, observe the response and relevant data without placing your hands near the mechanism. Meet the manufacturer's conditions and assess repeatability rather than just one reading.

If the circuit is correct, consider mechanical difficulties such as deposits, irregular movement or an actuation fault. These are diagnostic hypotheses, not a confirmed internal defect in our Transit. Delphi's general guidance explains why deposits and assembly condition should be assessed before deciding on replacement. F4: The basics of EGRs — what they do, how they work, how to troubleshoot

A dirty valve does not necessarily have the same problem as one with defective actuation. Do not force its stops or modify their position mechanically to make a code disappear. Restore correct operation rather than trying to deceive the feedback.

First check compatibility, installation and connections. Then establish whether the vehicle requires adaptation or a basic setting for the new part. Motorservice describes such recognition procedures for certain electronic systems; they are not a universal requirement for every EGR valve. F5: Adaptation to engine management

If the prescribed routine fails, save the result and continue diagnosing. Repeating it without understanding what is happening does not prove the ECU is faulty. An adjustment cannot correct the wrong part or a defective connection.

A new EGR does not, by itself, establish that the rest of the circuit is sound either. Comparing before-and-after behavior is more useful than starting another round of parts replacement without fresh evidence.

In this Ford context, P1303 points to EGR calibration, P042F describes control detected as stuck closed, and P1335 concerns the position reference at the stops. The descriptions are related but not interchangeable. F1: 2012 OBD-II Codes

When they appear together, organize the investigation around the shared assembly without assuming a proven causal chain. First establish what is happening to command, response and reference conditions, then decide which explanation fits the measurements.

On the Motores al Detalle Transit 2.2 TDCi, the three codes accompanied a limitation so severe that the van would not exceed approximately 50 km/h. Gerardo chose to replace the EGR based on the symptoms and his experience with that fault.

Reaching a lower connection required removing the cooling fan to gain room. After installing the new valve and refitting the removed items, the van was road-tested. It operated normally throughout that test without entering limp mode again.

The Ford Transit EGR replacement article describes the full intervention. We do not add a specific position-sensor measurement, recorded relearn or confirmed broken gear to that case. The final test establishes the observed behavior, not an unproven internal cause.

Check operation, scan again and confirm that the system responds correctly according to the applicable procedure. Keep the results for comparison if the symptom returns. Clearing codes should not be the only criterion for returning the vehicle.

If power loss prevents safe driving, do not try to keep up with traffic to finish a test. Arrange assistance or evaluation in safe conditions. During work, avoid unexpected actuator movement and hot or pressurized cooling circuits.

Ford P1335 is better understood as a question about the EGR position reference than an order to buy a valve. Assess the part, circuit and adjustment using vehicle-specific information, then verify the repair after the work.