P2E58 code meaning
Alternative Fuel Random/Multiple Cylinder Misfire Detected
Powertrain system Generic code P2Exx codes Check engine light
What P2E58 means
P2E58 is the collective misfire code for running on the second fuel, mostly CNG or LPG: misfires are counted while gas is burned, but no single cylinder can be blamed, or several each carry a large share. CARB treats a bi-fuel car as alternate-fueled only while it runs on gas and asks for the same misfire monitor as on gasoline; EPA likewise requires converters to keep OBD working on the conversion fuel. No carmaker documents P2E58 openly; Honda's Civic CNG and Roush propane trucks log gas-mode misfire with the ordinary P03xx codes. A GM patent checks both fuels: misfire on gas only points to the gas side, on both fuels to ignition. Likely culprits are an iced or poorly heated regulator or vaporiser, a clogged filter, low gas pressure or a lean mixture. One-cylinder faults are P2E59 to P2E60.
P2E58 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium
- Typical labor1 to 6 hours
- Clears after repairAfter a drive cycle
Symptoms of P2E58
- Rough running or jerking only while the engine runs on gas
- Bi-fuel vehicle switches back to gasoline on its own
- Check engine light on or flashing, gas-mode indicator may flash
Common causes of P2E58
- Most likelyGas pressure regulator or LPG vaporiser iced up or not heated enough (low coolant flow, moisture in the gas)
- PossibleToo little gas pressure at the rail – clogged gas filter, nearly empty tank or weak regulator
- PossibleWorn plugs or weak coils on several cylinders that cope with gasoline but not with the harder-to-ignite gas mixture
- PossibleLean gas mixture from an intake air leak or wrong gas-system calibration
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Alt fuel injectorsAlt fuel railIgnition coils
What each part of P2E58 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 58 | The exact fault in that area. |
What to do next
- Note P2E58 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P2E58
What does P2E58 mean?
P2E58 means "Alternative Fuel Random/Multiple Cylinder Misfire Detected". P2E58 is the collective misfire code for running on the second fuel, mostly CNG or LPG: misfires are counted while gas is burned, but no single cylinder can be blamed, or several each carry a large share. It is a generic code, so it means the same on every make.
Is it safe to drive with P2E58?
Drive gently and only to a workshop. With P2E58 the car can go into limp mode (reduced power) to protect itself.
Will P2E58 fail an emissions test?
Yes, it can. P2E58 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P2E58 to fix?
Difficulty: medium. A typical repair takes 1 to 6 hours of work. This is a job for a workshop.
Will P2E58 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.