stangmatt66

Hey ya'll just wanted to see if anyone was having problems with their CEL coming on becuase of a malfunction in the EVAP system. My CEL has been on 4 times and my PCM was just reset by Heritage Mazda in Huntington Beach under the advice of Mazda. Service was ok, but I really have to give props to the car rental company on premisis--Hertz.

Becuase all their cars were out already, the only vehicles available were a Nissan Altima and a Lincoln LS V8. Luckily for me, the Altima was gettin an oil change so I picked up the LS V8 for a few days free of charge. Have to say, it was the BEST rental car I've ever had! I love dropping off my $30k sports car for a $45k sports/lux car! NIICE!

Omicron

I have yet to have any CEL problems. Good luck with yours.

Rotary Nut

99% of the time it is because of a loose gas cap.

The evap system goes thru a self test (as required by OBDII and EPA regs) on start up by pressurizing the system and then monitors the leak down time. If the time it takes to leak down falls between a specified period of time it will flag it as a leak and pop the CEL light. This is most often caused buy not tightening the gas cap. If the cap is loose the tank and the evap system won't hold the pressure test and give you the light.

The new OBDII emmissons software is responsible for this.

stangmatt66

Sorry Rotary Nut, but I'm **** about tightening the gas cap. I always ensure it clicks 4-5 times.

The problem was not a lack of pressure in the fuel system (as verified by the dealership and Mazda), but an actual malfunction of the EVAP system and its pressure test. The system was registering "FAIL" when the system was pressurized fine.

Hope this clarifies my problem...

Rotary Nut

Yes it does and thanks.

I owned a 2002 VW Passat W8 that had the same problem. It was in the shop almost every week for the EVAP CEL (for a total of eight visits). They tightened the gas cap a few times and even replaced it twice. It was found that the pump that presserized the system for the leak down test had a pinhole leak in the diaphram and after they replaced it I never had the problem again. They "smoked" the system and the smoke was coming out of the pump. Have they checked the pump or whatever pressurizes the system for leaks? Have them pressurize the system with leak detection smoke and it will reveal the problem. It is similar to the stuff used by HVAC people.

I had to click my cap about 10 times because I was getting sick and tired having the clueless tech tell me I That I didn't know how to tighten my gas cap.

zoom44

i had that evap test failure CEL and got a flash for it. according to mazda this was caused by a software glitch. operating the keyfob or say the homelink at the same time you turn the car off could cause the evap test to fail the next time the car is started even with the gas cap tight. the reflash changes part of the software to correct this glitch and keeps the car from showing false evap test fails.

stangmatt66

Hmmm... Zoom44, my problem didn't occur when just operating the key fob, homelink and ignition. I had it happen once under that scenario (moving the car in and out of the garage), but it's come on while driving or just after starting the car. Sounds like it's just an intermittent software glitch. As a Software Test Engineer I know these things can happen sometimes...Let's just hope we haven't inherited any software glitches from Lincoln's Mark VIII...My neighbor had weekly software glitches with her's that wouldn't allow the car to start. The car was such a lemon.

Astor

That's because Lincoln's run on Windows
:D

stangmatt66

And RX-8s are on UNIX (SUN, AIX, HP), Linux or MacOS? lol

Astor

I would truely hope Unix