Vapor lock is back.....

[FactoryC3]

Vapor lock came back...Adding electric fuel pump and return line regulator...Dealer analyzed.
See this link for reliable info on vapor lock.
Ask Away with Jeff Smith: Understanding Vapor Lock--and How You Can Fix It! - OnAllCylinders

Will update with outcome.

 

[Vettehead Mikey]

To be very honest, I've never heard of a later C3 with a bona fide vapour lock problem ,assuming that the fuel return line from the g fuel pump is in place and working properly. Many owners, not understanding how the vapour return line works, inadvertently downgrade their cars by substituting a two Port fuel pump instead of the proper three Port fuel pump and then wonder why the car is suffering with engine stalling under certain conditions in hot weather.

Before ripping your car apart and modifying it with an electric fuel pump, why not verify that your car has the correct pump and that the return vapour return line is working properly.

I read the article that you attached in the link above and for the most part, the article is correct and accurate. However, I do see one of the posters bringing in the term percolation and using the old myth of putting Clothes pins on the fuel llinei.Vapour lock and percolation have nothing to do with each other, but sadly, much like pre-ignition and detonation. The two terms have commonly but mistakenly become interchangeable.

 

[FactoryC3]

Pump has return feature and line is clear

To be very honest, I've never heard of a later C3 with a bona fide vapour lock problem ,assuming that the fuel return line from the g fuel pump is in place and working properly. Many owners, not understanding how the vapour return line works, inadvertently downgrade their cars by substituting a two Port fuel pump instead of the proper three Port fuel pump and then wonder why the car is suffering with engine stalling under certain conditions in hot weather.

Before ripping your car apart and modifying it with an electric fuel pump, why not verify that your car has the correct pump and that the return vapour return line is working properly.

I read the article that you attached in the link above and for the most part, the article is correct and accurate. However, I do see one of the posters bringing in the term percolation and using the old myth of putting Clothes pins on the fuel llinei.Vapour lock and percolation have nothing to do with each other, but sadly, much like pre-ignition and detonation. The two terms have commonly but mistakenly become interchangeable.

I have been tracking this problem for 3 years. The pump was changed in a fix effort. Proper GM pump with return. Return line clear. Will update if this works...or not. I know a lot of folks who have vapor lock problems. Quite a few C3 late models posting in blogs having the identical issues. Pre-pump vaporizing where pressure is low. GM Dealer analyzed and confirmed. Just trying to share some info.