100% Free

No Scanner Needed

Carly logo
Prices

valentinascholz24

Matrix EVAP System Leak

My 2010 Hyundai Matrix with a gasoline engine is throwing me for a loop. The check engine light is on, and it stalls at idle sometimes. I suspect a fuel tank ventilation system leak, probably the activated charcoal filter failing. Anyone seen this before? Fuel efficiency is also terrible!

Summary of the thread

A 2010 Hyundai Matrix was experiencing a check engine light, stalling at idle, and poor fuel efficiency, suspected to be caused by a fuel tank ventilation system leak, likely due to a failing activated charcoal filter. The issue was confirmed to be related to the EVAP system, with the charcoal filter identified as a common problem. After replacing the defective filter, the check engine light was resolved, stalling ceased, and fuel efficiency improved.

Did this summary help you solve your problem?

4 comment(s)

larsmiller76

That sounds like a classic EVAP issue. The charcoal filter is a common culprit. The system captures fuel vapors to prevent them from being released. When it fails, it can cause all sorts of problems. Is the check engine light on constantly, or does it come and go? Have you noticed any hissing sounds near the fuel tank or filler neck? A faulty pressure sensor could also be the culprit by sending wrong values and influencing the air flow.

valentinascholz24 (community.author)

The check engine light stays on most of the time. I haven't noticed hissing sounds, but I haven't been specifically listening for that. Where exactly IS the pressure sensor located? Is it easy to get to?

larsmiller76

Consistent light points more towards a significant leak. The pressure sensor is usually somewhere along the EVAP line, often near the charcoal canister itself or the fuel tank. Without proper diagnostics like a smoke test, it's tough to pinpoint the exact location. Given the symptoms and your initial suspicion, I’d recommend taking it to a trusted mechanic. They can run a proper diagnostic and confirm if the activated charcoal filter is defective.

valentinascholz24 (community.author)

Thanks! I took it to my local shop, and you nailed it – defective activated charcoal filter! They replaced it, the check engine light is gone, and the stalling is fixed. Cost me about 275€ all in. Fuel efficiency also seems to be improving again!

rmh_community_comment_box_header

community_crosslink_scanner_headline

community_crosslink_scanner_intro

community_crosslink_scanner_title

community_crosslink_scanner_price

community_crosslink_rmh_headline

community_crosslink_rmh_intro

community_crosslink_rmh_title

community_crosslink_rmh_subtitle

community_crosslink_rmh_brand

HYUNDAI

community_crosslink_rmh_model

MATRIX