I read on this board that if I am going to keep my 1991 CRX si ECU that I will need along with a better fuel pump, fuel injectors, and FMU, a check valve to fool the ECU when boosting.

I have two question about this.
1. If I do not have a check valve and I am boosting will the ECU freak out and cause erratic engine behavior?

2. Where do get check valves?

Thanks


[Modified by Teluan, 5:39 PM 9/3/2001]

 

I think you can check valves almost anywhere like a Napa. I got a few from Toyota.

 

The check valve does not allow the ECU to see boost from the map sensor. Buy a missing link metal check valve.

You will throw a code and the ECU will go into limp mode if it sees boost.

k

 

Buy yourself a "Missing link" MAP sensor boost bleeder. Act like a check valve, looks alot more "factory-ish" than a bunch of check valves hanging off the MAP sensor.

 

check valves are one way valves used to block the positive pressure going into the MAP sensor. what you want is a check valve before the map sensor that will block boost pressure... and another checkvalve to bleed the boost pressure. i used check valves for an aquarium for a while and the setup I had worked well. I also used a brass tee fitting to allow manifold pressure to be distributed to BOV, boost gauge, etc. missing link would be best, but if you're a cheapy then the fishtank c.valves will work.

 

I used these large check valves for domestics.

Echlin from NAPA part number 2-970.