well here is what i did i bypassed the selector valve and just have a pressure and a return going to the front tank.Runs and starts alot better the raw fuel out of the exhaust is gone.Now just have a slight misfire at idle and hesitation off idle if you quickly snap the throttle.

 

Reminder,
I hope you did the correction with one thing in mind, that is the fuel lines are under some pretty high pressure and UNIONS are not recommended.

 

I ran new nylon fuel line front to rear no unions.Runs alot better but now cold start runs great idles great.But once it reaches operating tempature it doesnt want to idle?

 

Going under this assumption,
When below a certain temp, when the system is in open loop and below a certain temp, the mixture is controlled by programmed info in the computer.
Once a certain time has passed,the oxygen sensors reach the prescribed temp, the system goes into closed loop , the info from the oxygen sensors is now used to control mixture.
We do not know at this time if the info from the sensors is getting to the computer or if the computer is doing its job.
Newer systems provide codes for many malfunctions , but older systems required the tech to do some detailed testing to verify the sensors were working correctly

I believe there is a vacuum leak that is causing the system to stall due to too much air. We did verify the fuel pressure was on spec, right?
One way to prove this theory is to disconnect and/or pinch off each and every vacuum hose you can find including the hose to the brake booster and PCV valve.
Another thing is if the problem is gone when RPM is high , there is a vacuum leak Don't forget to check and pinch off the hose to the vacuum reservoir.too.
I believe the EGR valve was verified not sticking open .,right?

 

I will check for vacum leaks as soon as i get time.The egr valve is new so is the o2s.I finally broke down and bought an obd1 code reader here is what i got.42,34,18 this was koer.

 

The code 34 suggests the EGR may not be opening as much as desired.
Did you ever get rid of the fuel pressure regulator that allowed 100 psi?


The 42 code is referring to the oxygen sensor heater circuit . . Might want to verify that has power to the heater circuit when the oxygen sensor cools down cools down from extended idle.

The 18 code suggests a possible problem with the spark output signal to the ECA. The signal could be missing , open or grounded.

With all that has been going on, I would suggest clearing all the codes and starting over because some of those codes could be from a while back.before some repairs were made.

You may need to invest in a good meter to check things like frequency to prove out MAP sensor operation. Also make sure the canister purge solenoid is not stuck open and allowing the canister to be constantly purging pulling in extra fuel.

 

Yes replaced regulator fuel pressure is 30psi to 40psi now.i will check into the egr alittle more tonight.any ideas on the code 18?