[goshawk823]

this happens while filling up the tank. open the gas door and drop the nozzle in, and all of the sudden, you have a mild cam...

I've done this and it behaves like this for a few seconds and then smooths out.

[Ajmalian]

Originally Posted by VABarn

For starters, it's against the law to fill up a vehicle in a lot of states while the engine is running, so you might want to ask your buddy to double check the local laws on that one. Second, I wouldn't be surprised if it was some sort of breaking of a vacuum that is causing the issue.

I'm sorry but could you elaborate? What do you mean by breaking of a vacuum?

Originally Posted by KMPrenger

Turn it off while filling up.

/End Thread

I think the answer to your question is in my little writeup all the way below.

Originally Posted by Mr. Meh

It could very well be unhappy with the seal breaking the vapor recovery system in the gas tank..

Also, as pointed out above.. It's inadvisable and probably illegal to fill up your gas tank while the engine is running.


EDIT -- I see you're listed as being in Dubai.. I don't know what the laws are there about leaving an engine idling while gassing up, but you might want to check that.. Here in the USA, it's illegal.

I'm guessing you and VABarn are more or less on the same track about seals and breakage of vacuums I'm assuming. You reckon you could elaborate?

Originally Posted by Cameron27

Given the context I am assuming "gassing up" means pushing the gas pedal in order to make the car accelerate faster.

Idk what to do. Your friend should take it to a certified service place, or a mechanic, depending on if this is covered by warranty and who he prefers working on the car. It's not total rocket science: the car isn't working properly, get it checked out asap or stuff might get damaged worse than how things are currently, or worse someone could get hurt.

No no, gassing up meant filling gas.

Originally Posted by nancygrl

You said, "He claims his car drives and idles smooth and fine." idles rough and shakes while "gassing up"....We're guessing that you mean "re-fueling" or "filling up" the car with gas.
If this rough running is because your friend leaves the car running while filling the tank with gas...Tell him to shut it off before re-fueling....End of problem.

You too...please read my write up below.

Originally Posted by goshawk823

this happens while filling up the tank. open the gas door and drop the nozzle in, and all of the sudden, you have a mild cam...

I've done this and it behaves like this for a few seconds and then smooths out.

Never happened before. Just started and idles rough throughout until you stop filling and drive off. That's when it smoothens out.






Ok, so I appreciate everyone's opinion on my writing skills...ha ha very funny!!


However, what I did mean was that the rough idling happens ONLY while filling up gas and for those of you who suggested to switch the car off while filling gas....just because you look away doesn't mean a problem doesn't exist. I mean none of my cars have ever done this and neither does my current ZL1, then why should this 1LT? I mean it just doesn't sound normal. And it's something that was never there. It just recently started.

And finally, in Dubai, yes it is recommended to switch your engine off at the gas station while filling gas, however no it is NOT a law. In our defense, during summer we often have to deal with temperatures well north of a 130 degrees...so nobody switches their car off, especially during summer because even 3 minutes of 'engine off' time is enough to make your car a mobile oven. We behave ourselves more during better weather though.

Now, any suggestions on what the issue could be?

[ZED SLED]

Your answer is in post 5. This is the same as starting your car with the gas cap off. Not always but more often than not it will do this and throw a code. This is why there is a label on your gas cap that says 'turn until 1 click'. But now I'm wondering if this is an issue with 6th gens since they have no gas cap.

[Ajmalian]

Originally Posted by ZED SLED

Your answer is in post 5. This is the same as starting your car with the gas cap off. Not always but more often than not it will do this and throw a code. This is why there is a label on your gas cap that says 'turn until 1 click'. But now I'm wondering if this is an issue with 6th gens since they have no gas cap.

I was just gonna say, 6th gens don't have gas caps....

[Gutling]

When his car explodes or catches fire because he is filling it up while running, problem solved! Seriously just turn it off, this is a non-issue. There is a reason its illegal in most places.

[ZED SLED]

Originally Posted by Gutling

When his car explodes or catches fire because he is filling it up while running, problem solved! Seriously just turn it off, this is a non-issue. There is a reason its illegal in most places.

What would cause it to catch fire or explode? It's just a CYA revenue collector law. Just like here in NY it's illegal for gas pump nozzles to have the catch that keeps the trigger open while you clean the windshield. Yet most other states have them. This is what sucks about no gas cap anymore. Tether is the right length to jam the cap in the trigger while you fill up. But probably a hefty revenue collection if Buford T. Justice sees it and needs to fill the coffers.

[Need4Camaro]

Originally Posted by Gutling

When his car explodes or catches fire because he is filling it up while running, problem solved! Seriously just turn it off, this is a non-issue. There is a reason its illegal in most places.

If your car explodes while refueling, trust me when I say it was already on borrowed time.

[Gutling]

Was more of an exaggeration lol. And I have noticed the trigger holders disappearing in the last few years.

[HDRDTD]

Originally Posted by Gutling

When his car explodes or catches fire because he is filling it up while running, problem solved! Seriously just turn it off, this is a non-issue. There is a reason its illegal in most places.

Maybe a non-issue in NC, but when it's 130 degrees or better? Are YOU going to turn your air conditioning off ? (grin)

[Factorypilot]

Originally Posted by Need4Camaro

If your car explodes while refueling, trust me when I say it was already on borrowed time.

[Dustya]

All Comments aside about shutting the car off. Because obviously this is not what the OP wants to do. And he clearly stated his other cars do not do this including the ZL1..

My thoughts would be your other cars are higher performance engines with much greater fuel flow and pressure.. Where as creating a "Vacuum Break" does not effect it the same way the 1LT does..

Have him try "gassing up" when the tank is at 3/4 full and see if the results are the same.. If you are filling up at near empty or even 2 or 3 gallons in the tank you could simply be creating some sort of air in the lines by interrupting the fuel flow.

Also these in tank fuel pumps are all in one design the sending unit fuel pump etc.. is all in one... You could possible be dumping gas right onto the sending unit while its trying to operate normally and its getting confused. /shrug..

These are just ideas.. I would have him try to fill up when there is more gas in the tank and see if the problem is the same... or simply just have him open the fuel door while the car is on and see if it happens if it does that pretty much shows you its a vacuum issues.


Now back to the explosion option... These in tank pumps are sealed well however adding air oxygen into the tank while its running especially if the tank is low on gas is always a risk with submerged style pumps.. The chance is low as you would need spark and extra oxygen to ignite the fuel but your still taking a risk as low as it might be its a risk.

hope this information helps you in some way.

FYI- If turning the car off is a issue while refueling once the car is off press and hold the start/stop button for 8 seconds this will give you full access to all your controls put the air on recirculate and let the cool air just recirculate in the cabin while you fill up.

[Artos]

I burn about 35-40 gallons a day in my company truck & it starts once in the AM till I get home...guess I'll stop when I blow it up. You see this in the oil patch as we like our AC in South TX.

My ZL1 did the rough idle when filling up as well...didn't like it so just turn it off now. Not really sure why as I've never had another vehicle do this either.

[Hyper16]

Originally Posted by ZED SLED

What would cause it to catch fire or explode? It's just a CYA revenue collector law. Just like here in NY it's illegal for gas pump nozzles to have the catch that keeps the trigger open while you clean the windshield. Yet most other states have them. This is what sucks about no gas cap anymore. Tether is the right length to jam the cap in the trigger while you fill up. But probably a hefty revenue collection if Buford T. Justice sees it and needs to fill the coffers.

Static electricity. The idiot at the pump next to you smoking a cigarette. It has happened. Hence the law. Just like the warning stickers on everything.

[ISHLISS]

Tell him to shut off the car and fill up, if the problem persists then that's not the issue. If it fixes the issue, he has a choice to turn off the car or deal with the rough idle.

Seems pretty simple to me.