stalling again...


peiserg

GT Owner
Aug 15, 2010
283
Phoenix, az
Car has 30,455 miles on it. Just started stalling today here in phoenix. temps were about 100F locally.

I replaced the fuel filler 3,000 miles ago. First thing i did (after cursing the fuel flapper door) was check the fuel flapper door... and it is fine. I even ran my finger under it, and pulled up, in case the tab was starting to drop down. Anyone who has opened one up knows what i mean. the tab holds the spring loaded flapper in place. it can slip down and eventually off.

no movement on the flapper door (meaning, it seems to be functioning normally).



No codes either. the car died 4 times today!! same exact symptoms as my old filler neck issue, minus the codes. Idle hunting a little, and occasional engine dying.

Oh, BTW, i DID just top off the tank before this started happening. I use a long plastic funnel to avoid ANY potention for damage to that flapper. My flapper still has its hymen. it has never been breached by cold steel.

K guys. i searched and found tons of fuel filler issues. i don't think this is it. Wouldn't a bad O2 sensor (another suggestion) throw a code??
 
H

HHGT

Guest
What brand of fuel? Shell?
 

2112

Blue/white 06'
Mark II Lifetime
Does the funnel allow you to "over" fill? I have seen others say that is a problem.
 

nota4re

GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
Feb 15, 2006
4,277
Long shot, here.... what kind of air filters are you using and was it windy?
 

gtjoey

Keep Smiling - GT Owner
Mark IV Lifetime
Oct 14, 2005
3,454
Yeah, just a little more info...
Its stalling everywhere, with a full tank?
There are 3 flaps in the gas pipe, so even if the top one is good another might be weak.'Also you say you have no codes , how much gas is in the tank now.
You didnt close the clam shell side vents ?
No after market air cleaner? or k+n filter?
stalling no matter what after all the above and no codes is vaccuum/compression/sensor leak some where or crap fuel...
good luck,run a full scan at the dealer and take all the guess work out, its a 3 minute cycle test.......good luck...gtjoey1314
Just reading over your post again, if you used a LONG funnel, you might have broken a sping in the middle or bottom flap that you cannot see........run the cycle test, it will tell you one two three....
 
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peiserg

GT Owner
Aug 15, 2010
283
Phoenix, az
To answer some questions..

yes it was shell gas.

yes i overfilled. More so than usual, actually. normally i lose about 15-50 cc's of gas using my funnel method, because the tank "fills" while there is still fuel in the funnel being fed into the tank. This time it tried to top it off after the initial spill over. I don't normally do that.

gtjoey.. i've dissembled the original flapper that i replaced... there was only a single flapper valve (spring loaded one you knock off when inserting gas filler hose) there. If there is one hidden in the long aluminum pipe that goes to the tank i don't see any evidence of it externally (no evidence of a spring being soldered to the inside of the filler pipe from the outside). the funnel may be pushed maybe 3 inches beyond the upper flapper valve when i fill the tank.


oh yeah regarding filters. stock air filters, replaced about 800 miles ago by Rich Rovack. No other mods aside from exhaust (Ida) and pulley and tune (Heffner...no issues i've noted). not a really windy day either.
How do i run the cycle test?

Yes, the tank is pretty much full... although now it does have about 50 miles on it. but it was stalling and idling strangely with about 15-20 miles on the tank.
 

nota4re

GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
Feb 15, 2006
4,277
Well, it's fuel, air, or spark. There. That narrows it down!! Likely it is not spark as it would be lowest on the suspect list. Fuel? Well, the symptoms sure sound darn familiar to the fuel filler neck problem. I sure hope that this is not is as you have already "been there, done that." Still, a very high candidate.

The other potential is air. Might as well pull your air cleaner box out (easy!) and inspect the filters for any anomolies. Also, look at the MAF sensor and maybe clean it with some approved MAF cleaner aerosol. Finally, you might remove (once again quite easily) the idle air control valve and clean it.
 
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Howard

GT Owner
Mark IV Lifetime
Apr 26, 2007
1,148
Florida/North Jersey
Hooking a code reader up to the OBD port to read any pending codes might provide a clue. Pending codes won't throw a Check Engine Light......yet.

Howard
 

texas mongrel

GT Owner
Mark II Lifetime
May 3, 2009
1,670
Houston Texas
about every 5-6 tank fulls, I get this problem - no codes showing, but funky idle and tendency to stall. My solution is to pull back the sliding fuel valve and wiggle/poke the flapper with my finger. Sometimes I can feel the flapper 're-seat' itself but mostly I can't. Regardless, this has so far been a 100% cure for the problem. Good Luck!
 

gtjoey

Keep Smiling - GT Owner
Mark IV Lifetime
Oct 14, 2005
3,454
I would take it to a dealer and run the cycle test, it will take them 10 minutes and all the guess work will be done...gtjoey1314
 
H

HHGT

Guest
To answer some questions..

yes it was shell gas.

yes i overfilled. More so than usual, actually. normally i lose about 15-50 cc's of gas using my funnel method, because the tank "fills" while there is still fuel in the funnel being fed into the tank. This time it tried to top it off after the initial spill over. I don't normally do that.

gtjoey.. i've dissembled the original flapper that i replaced... there was only a single flapper valve (spring loaded one you knock off when inserting gas filler hose) there. If there is one hidden in the long aluminum pipe that goes to the tank i don't see any evidence of it externally (no evidence of a spring being soldered to the inside of the filler pipe from the outside). the funnel may be pushed maybe 3 inches beyond the upper flapper valve when i fill the tank.


oh yeah regarding filters. stock air filters, replaced about 800 miles ago by Rich Rovack. No other mods aside from exhaust (Ida) and pulley and tune (Heffner...no issues i've noted). not a really windy day either.
How do i run the cycle test?

Yes, the tank is pretty much full... although now it does have about 50 miles on it. but it was stalling and idling strangely with about 15-20 miles on the tank.

I had this happen to me twice after a Shell fill up in the Red GT and once in the Heritage on its one and only drive. It also happened once to RVKing here on the forum after he filled up at Shell as well. The problem has never re-ocurred after I swore off the Shell fuel at least for the GT. I know Jim aka RVKing also stopped using Shell after his incident. Coincidence, maybe!
 

peiserg

GT Owner
Aug 15, 2010
283
Phoenix, az
for a recent update...

no stalling today. i ran the car hard several times, and randomly let off the gas many times during today's driving. There were a couple of times the idle wobbled a little, but no stalling or near stalling.
 

GTdrummer

GT Owner
Mark II Lifetime
Le Mans 2010 Supporter
Mar 13, 2010
2,119
Richmond Virginia
Shell is closest to my house. I have been filling GTs and Vipers there for years--no issues.
 

RALPHIE

GT Owner
Mar 1, 2007
7,278
I will alternate between Chevron (most of the time) and Shell (if I'm running low), with an occasional fill-up at Costco. I like the Chevron for the Tecron additive, as I've been told it's the best for the injectors.

Never had any problems (knock on wood).
 

gtjoey

Keep Smiling - GT Owner
Mark IV Lifetime
Oct 14, 2005
3,454
Funny about shell, last trip with the LT and the trailer I always look for sunoco and we had to get shell.....Ive got nothing against shell but it felt like half the tank was water.........knocking and got horrible gas mileage. Still think its your filler pipe, but shell isnt on the top of my list....gtjoey1314
 

peiserg

GT Owner
Aug 15, 2010
283
Phoenix, az
i agree it acts like the filler pipe... but having been down this route, i was CONSTANTLY getting the evap code pulled off the motor. no such issue this time... so idk...
 

gtjoey

Keep Smiling - GT Owner
Mark IV Lifetime
Oct 14, 2005
3,454
i agree it acts like the filler pipe... but having been down this route, i was CONSTANTLY getting the evap code pulled off the motor. no such issue this time... so idk...

My 1314 was one of the first to be diagnosed years ago......Once the dealer puts in on a run cycle test, EVERYTHING will be uncovered, its neat , it starts the car....runs the rpm up and down, its like the car is possesed......Just do it you wont regret it........gtjoey1314
 

viva gt

GT Owner
Sep 15, 2010
419
toronto canada
the info below is from my gt tech

"Code P0455 on a GT, if the fuel filler “flapper” is good then I would be looking at the VMV (vapor management valve)

The fuel filler pipe will never cause a drivability problem but a sticking VMV can cause all kinds of low speed & intermittent drivability problems including a P0455, P0456 & P0457.

Item 1D in the PDF file"

i don't know how to attach a pdf. send me a pm with your email and i will send to you.
 

peiserg

GT Owner
Aug 15, 2010
283
Phoenix, az
Thanks for the info. I've driven several times and had no repeat. I'm wondering if my overfilling the tank did it? If it recurs then I will definitely go to the dealer for a full diagnostic run down.

Viva, I will have to disagree that the filler valve does not cause problems. My car stalled all the time until i fixed it.
 

viva gt

GT Owner
Sep 15, 2010
419
toronto canada
Viva, I will have to disagree that the filler valve does not cause problems. My car stalled all the time until i fixed it.[/QUOTE]

sorry, i was only relaying info supplied by my ford tech. i am only trying to help.
 
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