Check Engine light comes on only when it's cold out.

Reply

  #1  
Old 01-16-15, 12:07 AM
Banned. Rule And/Or Policy Violation
Thread Starter
Join Date: Oct 2010
Location: Canada
Posts: 448
Check Engine light comes on only when it's cold out.

Hi

I have a 1998 Chevrolet Cavalier with a 2.2 liter 4 cylinder engine and an automatic transmission.

When it's quite cold out, the "Check Engine" light comes on on my dash board. I phoned up a guy I take my car to for repairs, and he told me to bring the car to his place the following Monday. Over the weekend, the Check Engine light went off, but I figure that the fault code would still be stored in the computer's memory, so I brought the car to the guy hoping he could figure out what WAS wrong.

He hooked up his computer to the car and told me the fault code was for a problem with the "Evap Sensor". Since then, the Check Engine light has come one and gone off again more than once, and I've noticed that when the temperature is mild, it goes off.

My mechanic told me that it could very well be that the cold temperatures may be causing the gas cap seals to be stiff and not seat properly on the end of the filler tube. He also said I shouldn't worry about it because it would probably disappear once the warmer weather comes in spring.

I'm wondering if the guys in here would agree with that assessment. I'm willing to buy a new gas cap if you guys figure that would resolve the issue with the gas cap not sealing properly, or would the new one behave the same.

I'd like to correct this problem if possible, but I don't know enough about cars to know whether the problem is likely to be the gas cap or whether another gas cap would work any better.

I was thinking I could go to the auto wrecker and get a new gas cap for a buck or two just to see if that corrects the problem.
 
Sponsored Links
  #2  
Old 01-16-15, 03:54 AM
Forum Topic Moderator
Join Date: Mar 2005
Location: USA
Posts: 43,395
I'd try a new gas cap. Caps generally don't cost a lot so it wouldn't be a big deal if you bought a new cap and that didn't fix the problem. I wouldn't bother with a used cap unless it was free.
 
  #3  
Old 01-16-15, 04:16 AM
the_tow_guy's Avatar
Group Moderator
Join Date: Feb 2001
Location: SW Fla USA
Posts: 11,541
I agree with Mark; caps are pretty cheap compared to other parts in the system and you'll either get a fix or will eliminate one possible culprit.
 
  #4  
Old 01-16-15, 05:18 AM
Join Date: Mar 2005
Location: USA
Posts: 6,126
I had a similar problem on my 1999 GMC Jimmy and a 2000 Blazer.

I tried a cheap generic gas cap and that did not work. I went to a dealer and bought original caps and solved the problem. - That was about 3 years ago.

I still have to make sure it put on properly since it seems to be a little "touchy". - My wife is notorious for doing a poor job when refueling.

Dick
 
  #5  
Old 01-16-15, 09:27 AM
Banned. Rule And/Or Policy Violation
Thread Starter
Join Date: Oct 2010
Location: Canada
Posts: 448
Thanks for everyone's responses.

If the car seems to start and run perfectly well with the "Check Engine" light on, would it do any harm to just leave the gas cap alone and keep using the car the way it is? (I mean, besides the "Check Engine" light burning out prematurely.)

My mechanic told me "Not to worry about it.", so I presume he doesn't think the problem is a serious one. Another thing I was thinking I could do is just wait 2 months for the weather to warm up and see if the light goes out permanently.
 
  #6  
Old 01-16-15, 09:31 AM
Forum Topic Moderator
Join Date: Mar 2005
Location: USA
Posts: 43,395
The only downside to running with the check engine light on is it won't alert to problems since you are already used to it being on. I know of a couple of vehicles that have been running for a few yrs with the check engine light on
 
  #7  
Old 01-17-15, 12:38 PM
Banned. Rule And/Or Policy Violation
Thread Starter
Join Date: Oct 2010
Location: Canada
Posts: 448
OK, Thanks Marksr.

I'll probably just drive it the way it is until spring. If the Check Engine light comes in the the warm weather, I'd try getting an old gas cap or three from the auto wreckers.
 
  #8  
Old 01-17-15, 02:15 PM
Forum Topic Moderator
Join Date: Mar 2005
Location: USA
Posts: 43,395
Personally I wouldn't pay for a used cap. Autozone lists one for your vehicle for $12
 
  #9  
Old 01-17-15, 03:42 PM
Banned. Rule And/Or Policy Violation
Thread Starter
Join Date: Oct 2010
Location: Canada
Posts: 448
I woulda done that, except for this:

"Concretemasonry

I had a similar problem on my 1999 GMC Jimmy and a 2000 Blazer.

I tried a cheap generic gas cap and that did not work. I went to a dealer and bought original caps and solved the problem. - That was about 3 years ago.

I still have to make sure it put on properly since it seems to be a little "touchy". - My wife is notorious for doing a poor job when refueling.

Dick"

If I buy a cheap generic gas cap and the problem persists, what then?

I expect a gas cap from a Chevrolet dealership would cost 5 times as much as one from Autozone.

I'm thinking I can find out from the autowrecker what years and on what vehicles GM used that same gas cap, and see if I can get one from the latest model year they were used. I'm betting I can get much newer genuine GM Delco gas caps at three for a dollar from an auto wrecker.
 
  #10  
Old 01-17-15, 05:44 PM
Member
Join Date: Jun 2013
Location: usa
Posts: 103
I doubt its the cap......they make gas cap testers but if parts stores had them they would not make any money selling gas caps for evap codes.I have seen this on older cavalier with code p0440.the gas filler neck has a plastic insert that forms the mouth that meets metal tube......it leaks where plastic meets metal......have to use a smoke machine and pinch off hose at gas tank and use a special gas cap adapter with a hose on it to attach smoke machine....then you see smoke and dye where plastic meets metal pipe on filler neck.
 
  #11  
Old 01-17-15, 08:16 PM
Join Date: Mar 2005
Location: USA
Posts: 6,126
Based on my experience (1999 Jimmy), if I fill and put the cap on correctly, it take several start-ups or a period of running to erase the code. If I am sloppy when the cap is put on, the light seems to stay on. Fortunately, always have my reset odometer to tell me how many miles I have driven on a tank. - My car must have either a problem with the tank or the gauge since it can swing from 1/4 to 3/4 at an idle when the fuel level drops below 1/2 tank, but I always have the odometer for insurance. One of these days, I will get fixed, but removing the fuel pump or the instrument cluster is not reasonable in the cold weather, so I will turn it over my mechanic (Honest Eddie as my wife calls him), but he works by the calendar, and not the clock, so he may be done until after 6:00 PM

My plastic cord that attaches the the cap to the car broke, I bought a generic replacement cap somewhere. I tossed it after a few weeks and went to a dealer to get a good one and not have seen a problem since then.

Dick
 
  #12  
Old 01-18-15, 08:22 AM
Banned. Rule And/Or Policy Violation
Thread Starter
Join Date: Oct 2010
Location: Canada
Posts: 448
AutoJoe:

I had the gas tank and fuel pump assembly on my car replaced just this last September.

If you're saying that there's a vapour leak where the metal filler tube meets the tank, then would I be able to confirm that by filling up the tank completely so that even the filler tube is full of gas, and then checking to see if gas is leaking out of my car below the right side of the gas tank? (My gas door is on the right side of the car.)

I'm thinking that if gas vapours are leaking out there, then the gasoline itself would also leak out through that same hole(?).

Also, I'm thinking my best gameplan would be to take the car back to the mechanic who replaced the tank and fuel pump for him to check if anything's come loose, and if he can't find anything wrong to take the car to a Chevy dealership for them to find out what's wrong and why. Would you agree?
 
  #13  
Old 01-19-15, 06:36 AM
Member
Join Date: Jun 2013
Location: usa
Posts: 103
I have seen evap small leak codes that several garages can not find even with a smoke machine.The only thing you could do is try a gas cap and take to a shop that is ase certified and have smoke tested.......your looking for a needle in a haystack.there is a new device that when the smoke is introduced with c02 you take a c02 detector and run along lines and components and when sounds you spray a foam that changes color.most of the time a smoke machine with the uv dye will show a leak but there are those that need the new technology to find them.I wish I could be more help.
 
  #14  
Old 01-19-15, 06:39 AM
Member
Join Date: Jun 2013
Location: usa
Posts: 103
the filler neck where plastic insert meets metal tube the crack/gap is so small to allow vapor and not fuel and when you get gas the spout is beyond this point anyway.
 
  #15  
Old 01-19-15, 08:05 AM
Banned. Rule And/Or Policy Violation
Thread Starter
Join Date: Oct 2010
Location: Canada
Posts: 448
Well, it's definitely an intermittent problem. Day before yesterday the Check Engine light was on. Yesterday it wasn't.

I'll take the car back to the mechanic who installed the gas tank and fuel pump assembly and ask him to have a look to see if there's anything he can tighten or whatever to correct the problem.

If that doesn't do any good, I'll try explaining my dilemma to the nice man at the Chevrolet dealership parts counter and ask him if I can just try a new gas cap for a couple of days to see if that solves the problem. I expect I'm not the only one with this issue, so maybe they have a "loaner" gas cap on hand. I don't want to start spending a lot of money on smoke testing a 16 year old car if it starts and runs fine despite the Check Engine light shining bright as Rudolph's nose.

Thanks for your time and typing, Autopro.
 
  #16  
Old 01-20-15, 07:12 AM
Member
Join Date: Jun 2013
Location: usa
Posts: 103
if you did not have problem before work was done then something was disturbed by mechanic.
 
  #17  
Old 01-20-15, 09:21 AM
Banned. Rule And/Or Policy Violation
Thread Starter
Join Date: Oct 2010
Location: Canada
Posts: 448
Perhaps, but if I were the mechanic, I'd say that if I had the gas tank and fuel pump replaced in September, 2014 and the problem didn't develop until January, 2015, there's no reason to believe they're related. Something could have loosened up, and I'll take the car to the mechanic to check it, but there was a good three months of driving between the two events, and so I can hardly claim the two events are related.

My mechanic is telling me that there is an O-ring on my gas cap. I'm going to try replacing that 0-ring and cleaning the surface it seals against to see if that does any good.

I'm having my left knee replaced with a high tech mechanical hinge this coming Friday afternoon, so I won't be doing anything until I am fully mobile again.
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
Display Modes
'