Why won't my car idle right?

[Cyulost]

I have been having problems with my idle since I installed my novi 2000. So far this is what I have noticed:

1. The bypass valve and boost gauge are connected to the empty spot on the vacuum tree. The car starts and runs ok for a minute or two. Then the car surges bad, RPM's bounce from 500-750 approximately. My gauge reads about -10/-12 inches of vacuum. The car shakes and idles real rough.

2. Then all I did was unplug the bypass valve and boost gauge, and let the vacuum tree open so that you could hear it sucking in the air. Car idles damn near perfect at about 900 RPM's.

If I connect the valve and gauge back up the car stumbles and surges again.

Also, I have taken the car for a ride around the block, and it hesitates alot unless I'm accelerating.

I'm not the most mechanically inclined person and am looking for some direction to head in to try to solve this problem.

Thankyou,
Brandon

[Chuck]

Sounds rich to me.

If it runs better with a vacuum leak it sounds like it needs to be leaner.

Do you have an FMU??

What injectors??

list your mods so we can figure something out.

[Cyulost]

Chuck,
I am not running an FMU. I have the stock injectors in it right now. I have 42 Lb injectors but I wanted to fix the problem before I got involved in something else. The only mods I have is a 76MM C&L Mass air meter. And that is calibrated to the 19LBers. I still have the fuel pump, AFPR, sample tube, and 42Lb injectors waiting to go on. I do have a mechanical fuel pressure gauge on the cowl of the car.

Thanks,
Brandon

[Chuck]

What is the fuel pressure set at??

What ever you do dont put it into boost without the FMU hooked up, it will lean out and blow a head gasket or worse.

[root]

So you are running 19lb injectors, no FMU, and a NOVI 2K? Yikes I hope you are not pushing it.

Ian

[Hustler]

Definitely do not get into boost without the FMU on there with the 19's. Even with the FMU, the duty cycle on the injectors is beyond spec. I would be inclined to put the 42's and the meter on the car if it is calibrated correctly. Can you plug the t your using for the vacuum on the bypass and the gauge. I assume its the bypass you've concluded causes the surging. Do you hear any leaks anywhere?

[Cyulost]

Chuck, the fuel pressure is at 35-36PSI while the car is idle. This is with the stock regulator.

Ian, I am not pushing the car. I just want to fix this problem before I get involved in putting the 42Lbers in.

Thanks,
Brandon

[Cyulost]

Any ideas on what I can try?

[fullychargedgt]

I would just ditch the 19s...put the 42s in with the correct cal mass air and have a chip tune done.....why try and get the car to run good with what you have on it know when you are gonna change it and you will be back to square 1

Any idle issues or surging will be cleared up with the correct chip as long as there is no mechanical reason for the idle/surge probs.