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Severity: Low Code type: Generic (all makes)

P0458 Code: EVAP Purge Control Valve Circuit Low

The purge valve control line reads too low: lost power feed, open coil or a wire shorted to ground.

At a glance

Severity: 2/5 – Low2/5

Severity: Low

Meaning
EVAP Purge Control Valve Circuit Low
System
Emission Controls · Powertrain
Safe to drive?
Yes, short term
Typical repair cost
$10–$1,400
DIY difficulty
Easy

P0458 is used mainly by GM brands and some other makers that split purge circuit faults into low and high. The purge solenoid gets ignition voltage from a fuse, and the ECU switches its ground side. With the driver switched off, the ECU should see battery voltage on the control pin; if it sees close to zero instead, P0458 sets. Three things cause that: the power feed is missing (often a fuse shared with other emission parts), the coil or wiring is open, or the control wire is shorted to ground. That last case matters, because a control wire shorted to ground energizes the valve permanently: it stays open, pulling fuel vapor into the intake at idle and right after refueling, which can cause rough running, stalling and rich codes.

Can I keep driving? Usually fine to drive. If the engine stumbles or stalls after filling up, or idles roughly with a fuel smell, the valve may be stuck powered open; get it checked soon and avoid topping off the tank past the first click.

How to read P0458

How to read P0458P10243584
  1. P Powertrain
  2. 0 Generic (SAE)
  3. 4 Auxiliary emission controls
  4. 58 Specific fault

Symptoms

  • Check engine light, often with no drivability change when the circuit is simply open
  • Hard start or stalling right after refueling when the valve is held open
  • Rough idle and a rich code (P0172) from constant vapor flow
  • Oxygen sensor heater or vent valve codes at the same time if a shared fuse has blown
  • Fuel smell near the car after a few fill-ups when the valve never opens

Possible causes

Ranked by how often each cause is behind this code (editorial estimate).

  1. Blown or failing fuse on the ignition feed the valve shares with O2 heaters or the vent solenoid 26%
  2. Open coil in the purge solenoid 22%
  3. Control wire chafed and shorted to ground, which keeps the valve energized 18%
  4. Connector off, corroded or with a pushed-back terminal 17%
  5. Broken wire in the feed or control circuit 10%
  6. ECU output driver fault 7%

Diagnosis step by step

Diagnostic flow: P04581Look for company codes2Check the feed pin first3Test whether the valve is stuck open4Separate a shorted wire from a stuckvalve5Measure the coil6Command the valve after the repair

  1. Look for company codes

    P0458 together with oxygen sensor heater codes (such as P0030 or P0036) or a vent solenoid code (P0449) points straight at a shared ignition-feed fuse. P0458 alone points at the purge valve, its connector or its own wiring.

    Tools: OBD-II scanner

  2. Check the feed pin first

    Unplug the valve, key on, and measure from the feed pin at the harness to ground. You should see battery voltage. Nothing there means a fuse, relay or feed wire problem, not the valve, so trace the fuse before buying parts.

    Tools: Multimeter

  3. Test whether the valve is stuck open

    With the engine idling and purge commanded to 0%, pull the hose from the valve's canister side and check for suction with a vacuum gauge or your finger. Suction at 0% command means the valve is energized by a short to ground or is mechanically stuck.

    Tools: OBD-II scanner, Vacuum gauge

  4. Separate a shorted wire from a stuck valve

    Unplug the valve while it's pulling vacuum. If it snaps shut, the control wire is grounded somewhere; check it to chassis ground with the ECU unplugged. If it keeps flowing unplugged, the valve is mechanically stuck and needs replacing.

    Tools: Multimeter

  5. Measure the coil

    Measure across the valve's terminals. Most purge solenoids read somewhere around 15 to 35 ohms; open means a broken winding.

    Tools: Multimeter

  6. Command the valve after the repair

    Clear the code, then use the scan tool to cycle purge on and off while listening for the click and watching for P0458 to stay away. Let the EVAP monitor run over the next few days of normal driving.

    Tools: OBD-II scanner

Where the parts are

EVAP system: gas cap, canister, purge and vent valves – P0458123456
EVAP system: gas cap, canister, purge and vent valves
  1. 1Gas cap
  2. 2Charcoal canister
  3. 3Purge valve
  4. 4Vent valve
  5. 5Fuel pump
  6. 6Intake manifold

Repair options & costs

RepairDIY?Estimated cost
Replace fuse and fix the short that blew it Yes $10–$200
Clean or replace purge valve connector Yes $20–$150
Replace purge solenoid Yes $90–$300
Repair chafed control or feed wire No $100–$350
ECU repair or replacement No $600–$1,400

Rough US estimates for parts and labor; shop rates vary by region. Not a quote.

Notes by brand

Chevrolet

On many GM vehicles the purge solenoid shares an ignition-voltage fuse with the oxygen sensor heaters and the EVAP vent solenoid. A blown fuse there sets P0458 together with heater and vent codes, and the fuse will blow again unless the shorted component or wire is found.

Field data

Chevrolet 4 Volt

Source: NHTSA Complaints API (US government open data), analyzed by DTC mention.

Emissions / smog test impact

Will fail

P0458 turns on the check engine light and keeps the EVAP monitor from completing, which fails an OBD-II emissions test. After the fix, the EVAP monitor may need several days and a partly filled tank to run.

Frequently asked questions

How is P0458 different from P0443 and P0444?

They describe the same valve at different levels of detail. Makers that split the codes use P0458 when the control line voltage is too low, which covers a missing feed, an open and a short to ground. P0443 is the general circuit code, P0444 an open on systems that report it separately.

Why does my car stall right after I fill up?

If the purge valve is held open, fresh vapor from refueling rushes into the intake at idle and makes the mixture far too rich. A shorted control wire or a valve stuck open are the usual causes; fixing them cures the stalling.

Several codes appeared at once. Is the purge valve bad?

Probably not. When heater or vent codes appear alongside P0458, the common element is usually the fuse or feed wire they share. Find out what blew the fuse before replacing it.

Can I just replace the purge valve?

Only if the coil measures open or the valve is stuck. If the feed pin shows no voltage, or the control wire is shorted, a new valve won't fix anything and may be damaged.

Sources