gASCAP (engine light, odometer displays "gascap") 2008 Grand Caravan

[DrPizza]

Anyone have any guesses as to what's wrong? After I got gas a couple weeks ago, the engine light immediately came on. No problem - according to the manual, it will do that if it gets "bad" gas, and the problem will most likely resolve itself after the next fill-up.
Just to be safe, had autozone get the codes for me. None found.

Well, it's about 6 fill-ups later, and now the odometer displays gASCAP. Yes, the gas cap is on. Yes, it's screwed down until it goes click click click.


Any guesses as to what's making the car believe the gas cap isn't on?

 

[exdeath]

I think something is wrong with your gas cap.


...


Seriously though, just because it clicks doesn't mean it's sealing good, and the EVAP system will complain.

 

[Pulsar]

Pull the gas cap and check to see if there are gouges out of the o-ring seal on it. Also look at your filler neck and insure there are no cracks on it.

I have a car a couple years older than yours where the weld on the filler neck cracked and that gave me the gascap code almost constantly.

To check and see if it IS the gascap, put some dry gas in when it gets near empty, then fill it up. Put a light layer of gasoline or grease on the gas cap seal, and crank it down. Then clear the battery by pulling the battery cable from the battery and waiting 10 minutes. Reconnect it and drive it for a while. If it comes back, it is not likely that it's actually the gas cap, and it's time to take it into the shop.

 

[alfa147x]

I had this problem with my Civic just a couple weeks ago. What I have to do now is: The manual says make sure it clicks three times. I have to make it click 8 - 10 times for it to seal correctly. I think it's time for a new gas cap but this solution works ATM

 

[LTC8K6]

Something is wrong with either the gas cap or the canister vapor recovery system.

Probably covered under the emissions warranty.

 

[Zenmervolt]

Technically it's registering a slow leak in the evaporative emissions control system. Since this is usually the fault of the gascap, that's the message that it shows, but the actual cause could be a small leak at any point in the EVAP system.

ZV

 

[PhoKingGuy]

Its a Chrysler

 

[LTC8K6]

From 08 Grand Caravan manual:

Loose Fuel Filler Cap Message
² If the gASCAP message is displayed in the instrument
cluster, this signifies a leak or change in the evaporative
system is detected. Sometimes this is the result of
a loosely fitting (or possibly damaged) filler cap.
Tighten the fuel filler cap properly and press the
odometer reset button to turn the gASCAP message
off.
² Make sure that the fuel filler cap is tightened each time
the vehicle is refueled.
² If the problem continues, the message will appear the
next time the vehicle is started. See your authorized
dealer service center as soon as possible. See Section 7
of this manual for more information.

 

[boomerang]

2008 will be covered under the emissions warranty.

 

[COPOHawk]

I had a similar problem on my 2007 Buick Lacrosse (3.8L)...I replaced the gas cap for under $20 directly from the dealer. The emissions system is overly sensitive in this area...didn't detect any physical defect with the old cap...but the new cap fixed it.

BTW...isn't the GASCAP message kind of obvious?

 

[DrPizza]

2008 will be covered under the emissions warranty.

No it won't. Bought the vehicle with about 30k on it. It's now over 100,000 miles; warranty has long ago expired. I'll check it all over tomorrow. I cringe at the thought it's something with one of the lines, or at least, I cringe at the thought that the problem is going to be difficult to find. I won't bother with the shop though.

And, if I get a chance tomorrow, I'll post a picture of what happens when you let the muffler go for a couple weeks while you're on vacation with a deep, but not too loud sound because it cracked down the length of the weld when it hit the cold water (I think) backing the boat into the lake. (2001 grand caravan) - a lot of heat from the exhaust was directed directly at the gas tank. The gas tank partially melted and deformed. On the way home, the seam on the gas tank split open, allowing me to put no more than about 5 gallons in at a time unless I wanted it to overflow. Relatively cheap and easy fix - pulled the tank off and replaced it with one from the junkyard ($50). I took it to a muffler guy I hoped would be able to reweld that seam (he couldn't). Other than the cracked weld, the muffler was in perfect shape. I'm not positive that it couldn't have been rewelded; it's possible he just wanted the business for replacing the muffler which is trivially simple to do. So we (son actually) stuck in a new muffler, $80, including clamps. But, according to that guy, he has seen a lot of mufflers in "good" shape on dodges except for splits on that seam. That makes it look like a major design flaw - when it splits, it's blowing directly on the gas tank.

 

[COPOHawk]

I had a similar deal...buy the gas cap

Hopefully it isn't anything more expensive.

 

[boomerang]

No it won't. Bought the vehicle with about 30k on it. It's now over 100,000 miles; warranty has long ago expired. I'll check it all over tomorrow. I cringe at the thought it's something with one of the lines, or at least, I cringe at the thought that the problem is going to be difficult to find. I won't bother with the shop though.

Wow, that's a lot of miles. I was going to point the mileage limitation out, but I thought there's no way on a two year old vehicle. Hmm, close to three I guess. Yikes.

 

[DrPizza]

We go on a lot of trips.

Oddly, I set aside some time yesterday to work on it. When I went out to the car, the problem had ceased to exist. Weird.

 

[sdifox]

We go on a lot of trips.

Oddly, I set aside some time yesterday to work on it. When I went out to the car, the problem had ceased to exist. Weird.

Oh? Do you have to drive around the fainting goat babies so they'll fall asleep?

 

[mb]

We go on a lot of trips.

Oddly, I set aside some time yesterday to work on it. When I went out to the car, the problem had ceased to exist. Weird.

Time is usually the solution to gas cap problems. I had it happen on my 08 Accord not too long ago. Error in the morning, error free in the evening.