Stalling
 

I overfilled the gas tank a week ago. After driving the car for 10 miles it stalled. I opened the gas cap and pressure was released. After 15 minutes I drove it home. Today I took it out and after 15 minutes it stalled. I opened the gas cap and the same thing happened. After 15 minutes it started and I drove it home. New the service soon light is on. It has 41,000 miles on it. Any thoughts on gas cap or other causes?

Did you notice pressure release before you had the problem? When you filled the tank before? What year? OBD2 will set a code for fuel cap. I'd replace the cap and clear the codes. Just pull the ecm fuse for a couple of minutes. You could also let autozone pull the codes and go from there.

Hth,

Joe K

According to one of his earlier posts, it is a 1993, so OBD I.

How did you overfill it? Pump clicks off and there is a lot more to go. A gallon, maybe 2? Buy yourself a scanner. One that can read real time data and not a cheap code reader which is a paperclip with a fancy box around it. Check fuel pressure and spark quality.

How do you over fill a gas tank?

Stalling
 

From what have heard from the C4 forum is that if try to squeeze as much as you can in it can cause liquid to get into the charcoal filter causing pressure to buildup and the fuel pump cannot overcome the pressure.

Ridiculous!

This part is true -of most any car. It CAN happen. But...


This won't happen. No way. What could happen is the the engine could ingest fuel or fumes from the charcol canister causing and over rich condition. It's unlikely that this would cause it to stall and not run.

OP why haven't you pulled the code to see what the car is trying to tell you the problem is? That would be "step 1", here.

Stalling
 

Which code reader would you recommend? I put a new gas cap on it and ses light went off. Drove it for 30 minutes today and no issues. It has 41,000 miles on it. It is a 1993 LT1.

I'd recommend none. I'd use a paper clip or jumper wire to jump the terminals in the ALDl connector under the dash, then count the flashes to get your codes. See this 'how to', HERE

Cheap paper clip or a real scanner. Real scanning will give data which the code scanning will not. That comes at a price but saves aggravation. No free lunch.

Stalling
 

Started 10 minutes ago SES back on. Idling at 1500 rpms.

Taking it to a Corvette specialist unless I get a better suggestion.

Frustrating as it was my brother in laws since new. It is in near showroom condition but 26 years old.

Stalling
 

Is there some sort of pressure relief valve on the EGR or other emission system that may cause it. I would love to learn how to perform my own repairs.

Have not worked on cars since I restored a 1972 Trans Am in 1982.

Here is another link for reading the codes with a jumper wire (paper clip). On your 93 it will actually display the numerical trouble code directly, no need to count flashing ses lights. Check the code before making any guesses.


https://tech.corvettecentral.com/201...trouble-codes/

Stalling
 

The frustrating part is we driven the car for a 100 miles at a time over the 7 months we have owned it. This started 15 minutes after fueling it. Can the fuel pump operate effectively and then not and then operate effectively again?

Can it? Sure. Is it the issue? Without a pressure gauge on it or an idiot light on the pump, it is hard to tell. I need to see if the start up pressure is good, will it hold pressure and also pressure at WOT. Most important is when you have the problem is happening, what is the pump doing?

Stalling
 

There is no issue on operation at all until 15 minutes of driving. Acceleration is awesome.
https://cimg3.ibsrv.net/gimg/www.cor...48376557b5.jpg
https://cimg4.ibsrv.net/gimg/www.cor...975da80847.jpg
it won this award too. We would like to keep it the family as my brother in law passed away last June.

If the diagnosis is daunting would you recommend I take it to a professional?

What is happening at 15 minutes? Fuel pump not working? Oump not getting power? Spark from opti? ECM? If it dies and can restart, rap the ECM and see what happens. It might be the cold solder pieces of solder. It could be the opti failure when hot. It may be a Oump dying when hot, it might be the power to the pump.

Stalling
 

After 15 minutes of driving it stalls
If you try to start it tries and stalls immediately. Wait 20 minutes and it starts

Perfect. That allows me to try rapping the ECM to see if it improves and check spark from opti or fuel pressure