I'm brand new to the Forum and Desperate for Help.

I have a 1999 Honda Civic SiR (Canada Model - I believe in the US its an Si, came stock with a B16)
The car has a JDM B18C ITR Engine

The car often stalls, at random, but usually after driving for 30 minutes.

So far I've had the Fuel Pump and Filter Replaced
The EVAP has been smoked and no leaks detected
I've replaced the Gas Cap
I've replaced the Vent Solenoid for the EVAP

for the past month, the car will stall, any speed, any temp, after driving for 30 minutes. It's even done this on the highway. I determined if I opened the fuel cap, there would be a rush of air. I figured that maybe the fuel cap wasn't venting air in, and after driving for while, enough vacuum would be created to starve the fuel pump and the engine. I would do this, wait 1 minute and then the car would start. Changed the gas cap 5 days ago and the EVAP Vent Solenoid (valve) -- I was being told that the problem could be either of these. Drove car all weekend, no problems, seemed to have more power, never stalled.

Today the car stalled out while doing about 30km/h

Pulled into a parking stall, did the regular routine, checked gas cap (no rush of air this time). Tried to start, it seemed like the engine would catch for a second and then stall. Smelled gas in the car.
This time I pulled the 1/2 inch hose off of the EVAP canister vent valve, left it off, and the car started right up.

Any ideas now on what the problem might be?

Thank you.

 

I am sorry to hear about this! I have been chasing problems with the evap system on my swap (https://honda-tech.com/forums/honda-.../#post51107787)

My advice would be to assemble the factory service manual sections on the evap systems for both your engine and your body. Not sure what year your engine is. If it is JDM, I think you may have to add to make sure it can play with the body's system.

Good luck!

 

CEL codes? What ECU?

 

Very unlikely the EVAP has anything to do with your stalling. Easy test though-- drive with the gas cap loose, see if there is stalling.
The system is designed to form a slight vacuum in the gas tank. This prevents raw fuel vapors (VOC, HC) from getting into the air and causing smog.

One common reason for working a while, then stalling, and not restarting for a while, is the ICM, the module that drives the ignition coil. When it will not start, see if the ignition system is making sparks when the engine is cranked.