Service Engine Soon Light

rasal · August 17, 2004

Service Engine Soon Light came on today. I checked the owner's manual and it said I have an emissions problem. I was down to a half tank of gas, had not gone through puddles nor changed gas providers. I did add a fuel injector cleaner to the last tank of gas. The plugs and filters were recently changed. Any alternative other than taking it to the shop?

Thanks in advance.

MCourson · August 17, 2004

Take it to the nearest Auto Zone, or anywhere else that will read the codes for you (AZ is free) and that will tell you what is tripping the SES light. Could be a simple fix.

02 Blue Thunder · August 17, 2004

Definitely make sure and check the code the computer kicks out. I read in my owners manual that says the SES light is only for emissions. Mine was on because of my tranny slipping. The 4L60E are known for having some valve body issues I have since found out after replacing my whole emission system.

Kyle

atomoverride · August 17, 2004

remove the light bulb.....

03GMCinBC · August 17, 2004

Mine came on last friday. took it into the dealer on Monday and they said the computer read all was fine. They reset the computer to turn off the light.

a block from the dealership, it came on again. I took it back Wed and they found out they needed to order a part, they swapped out the mass airflow compontent on Friday.

The fix also read that a heater sensor was sticking open this time.

They fixed it for $00 under warranty and it hasnt happend again. Im happy....

rasal · August 18, 2004

Thanks to all. Stopped by Auto Zone. They read the code for free and the code indicated a small leak exists in the evaporative emission control system. He did not know for sure what would cause the problem but said it could be the gas cap and suggested I take it to a repair shop for additional information. I took it too a repair shop and explained the problem. The repairmen suggested I get a new gas cap (not knowing that solution had previously been suggested), disconnect the neg battery terminal to reset the computer and if the light remained on then I had another problem. Following his instructions, the light remained off. Nice to know some repair shops are not out for the bucks and do offer good advice.

freaker · August 20, 2004

I had the same happen on my '98 Z71 and it was a loose gas cap. The dealer said that the cap needs to click several times to be on correctly. If left loose and the ignition is turned on something like 20 times then the check engine light comes on. Once corrected/tightened and ignition is turned another 20ish times it will go off. I have tried this and it appears to be correct ..... real or myth????

asilverblazer · August 20, 2004

I know Ferds do that or something similar.

MemphisDoug · August 20, 2004

Loose gas caps are probably the most common reason for a check engine light to come on. Always make sure that the cap clicks a few times when you put it back on.