I bought an '89 IROC Z a few months ago and have a problem with gas station fill ups. I have to trickle the gas into the tank because the gas backs up in the gas tank filler neck and shuts off the pump. My mechanic checked everything and replaced the "evap purge valve". Took the car to fill it up and nothing has changed....filling up is still a problem. Can anyone offer any advice on possible causes to the problem? Many thanks! Bob C.

 

Sounds like a clogged air vent.

 

Thanks! Is the air vent part of the gas tank or something that is piped to a filter element under the hood. Sorry that I am mechanically at a loss on these things! BobC

 

Check this little guy out. Its mounted on the drivers side rear axle. Take it apart and clean it too. Comes from the tank.

 

Thanks guys! I will have my mechanic check it! Much appreciated!

 

I don't have the link handy, but somewhere here there's a detailed thread on how to disassemble, clean, and reassemble these. With a search, and some patience, you should find it.

As they are no longer made, fixing what you have is the way to go.

 

You see what Dave said here ?

Make DAMN sure your mechanic isn't the ham fisted know it all type that won't search out the thread here on how to clean that without breaking it ! As the man said , it's no longer made so in other words it's now made of unobtainum and you will be up shitz creek without a paddle if he does break it !

Good Luck

 

Many thanks guys! I will do the research on cleaning the vent, print it out and make sure my mechanic understands completely. I will also search those Camaro parts dealers to see if I can pick up a used one just in case!

 

Check the fuel filler neck. Some folks cut them (tank R&R) and splice it back together with a piece of hose. This will do it every time.

RBob.

 

https://www.thirdgen.org/forums/hist...ent-valve.html

 

Thanks RBob....I did check the filler neck and it is one piece from gas cap to tank....it is an after market tank but appears to be correct.

 

That's the one!

 

I think this may be the issue: it is an after market tank

As for the tank venting outbound, it is the job of the evap purge valve. Which your/his mechanic already replaced. It has a lower cracking pressure then the mushroom valve.

RBob.

 

Thanks to all and I have studied the postings from MJS422 on taking apart and cleaning the valve. I have just received a used valve and of course it is very dirty. I am very wary of taking it apart to clean it. Is it possible to simply soak the valve in soapy water to do a basic cleaning? Then, if that works, I will take apart and clean the valve that my mechanic removes from the car. Thanks, as usual! BobC

 

Just an update that my mechanic replaced the fuel tank vent valve with the "new" one I received from DavidTs in Canada......it works! Just filled my tank and it was flawless. Without the thirdgen members I would have been lost as to a fix. Thanks to all who contributed to the solution! BobC

 

It's nice when the repair is an easy one that actually works ! Thank You for reporting back , it's great to hear of your success .

 

Glad you got it going.

It's a repair I'm going to have to do in the near future.

 

Yes it is a repair and I will be taking the old valve apart to clean it and will keep it as a spare!