Recent Topics
Toyota 90915-YZZG1 Made in the USA
by Tmiller3063
12/19/14 04:17 PM
Mystery oil loss
by Mar57
12/19/14 04:05 PM
Brand new VW 2.0T- Castrol 0w40 ok?
by gijello
12/19/14 03:51 PM
An opinion please.
by hank55
12/19/14 03:50 PM
fixed the dreaded rust!
by Robertslowpoke
12/19/14 03:41 PM
Reading the dipstick on a GM 4.3l V6
by Sierra048
12/19/14 03:22 PM
Silk browser alternative
by possum328
12/19/14 01:53 PM
John Deer LA 105 Oil Recomendation
by AndySantoro
12/19/14 01:35 PM
Am losing brake fluid
by MalfunctionProne
12/19/14 12:56 PM
1991 350 Chevy Blazer Wont Start
by Milerhighlifeman
12/19/14 12:31 PM
Longest (continuously running) IC engine?
by expat
12/19/14 12:09 PM
Run cycles
by MalfunctionProne
12/19/14 11:29 AM
Newest Members
SCFarmer, LumpOfCoal, carguymitch, longball, probmxstyle
52227 Registered Users
Who's Online
99 registered (1bioguy, aa1986, 2oldtommy, 1foxracing, andrewp1998, 901Memphis, 6 invisible), 1456 Guests and 191 Spiders online.
Key: Admin, Global Mod, Mod
Forum Stats
52227 Members
66 Forums
223658 Topics
3546439 Posts

Max Online: 2862 @ 07/07/14 03:10 PM
Donate to BITOG
Topic Options
#2767398 - 10/09/12 09:26 AM Symptoms of a bad gas cap?
wolf_06 Offline


Registered: 06/11/12
Posts: 434
Loc: Atlantic, Canada
Any of you experience a bad gas cap? If this can affect engine performance, fuel trim or fuel pressure? fuel economy?

Thanks!
_________________________
2011 Chevy Cruze 1.8L 6AT
Pennzoil Platinum 5w30 - OEM filter

Top
#2767401 - 10/09/12 09:30 AM Re: Symptoms of a bad gas cap? [Re: wolf_06]
Quest Offline


Registered: 12/19/04
Posts: 6549
Loc: beaver land EH?
on OBD-II cars: a bad (not sealing properly) gas cap will throw you a code.

Q.
_________________________
"Internet discussion boards act as echo chambers for conspiracy dittoheads" A.Allen

Top
#2767404 - 10/09/12 09:32 AM Re: Symptoms of a bad gas cap? [Re: Quest]
Charlie1935 Offline


Registered: 05/18/08
Posts: 388
Loc: DuQuoin, Illinois
It will give a code for evaporation system leak usually.
_________________________
Charlie

Top
#2767417 - 10/09/12 09:53 AM Re: Symptoms of a bad gas cap? [Re: wolf_06]
440Magnum Offline


Registered: 02/01/09
Posts: 6475
Loc: Texas
Electric fuel pumps for EFI generate pressures on the order of 50 psi, the gas cap holds a pressure of 2-3 pounds. So at most its going to make a few percent difference in fuel pressure, and most likely not even that since the fuel pressure is usually regulated. So I'd say you'd never see a difference in performance at all, just the code for an evaporative emissions fault.
_________________________
'66 Dodge Polara & '69 Dodge Coronet R/T both 440/727
'08 Ram 1500 4.7/545RFE
'12 Challenger SRT8 392/6-speed
'99 Cherokee 4.0, '11 Grand Cherokee 3.6

Top
#2767479 - 10/09/12 11:19 AM Re: Symptoms of a bad gas cap? [Re: wolf_06]
WishIhadatruck Offline


Registered: 05/09/06
Posts: 1295
Loc: Grand Rapids, MI
The only thing I've ever noticed is that my check engine light comes on. I've never noticed a change in how the vehicle performs.
_________________________
1996 Buick Roadmaster Wagon
2014 Cruze Eco Manual
2003 2500 Suburban, 8.1L

Top
#2767495 - 10/09/12 11:39 AM Re: Symptoms of a bad gas cap? [Re: wolf_06]
Donald Offline


Registered: 03/21/04
Posts: 13760
Loc: Upstate NY
I drove for a few miles with the gas cap held neatly in the gas flap. No code or anything.
_________________________
2001 Jeep Grand Cherokee Laredo 4.0 - PP & M1
1999 Dodge Ram 2500 w/Cummins - Rotella T6 & M1
Amsoil ATF in both vehicles & Magnefine filter.

Top
#2767501 - 10/09/12 11:43 AM Re: Symptoms of a bad gas cap? [Re: Donald]
Trav Offline


Registered: 11/20/06
Posts: 10420
Loc: MA, Mittelfranken.de
It wont until the system runs an EVAP test.
_________________________
ASE L1, Master. Deutsch Meisterbrief.

Top