wg871

iTrader: (15)

I bought a Fast 90/90 from a firend and we put it on this weekend. We had to plug off some vacuum lines and deleted some stuff related to the air/egr. The car is acting like it has a vacuum leak. It is idleing high and the idle hangs if you touch the gas. If im cruising down the road and bump it in neutral it idles up to 1700-1800, just sitting in drive holding the brake it idles around 1,000. It feels like its trying to push through the brakes. The throttle body had a tiny hole drilled into the blade when I bought it, it idled fine on my friends car (it was tuned with this setup). Im not sure if I need to get my car tuned to adjust for the hole in the throttle blade? I know the tune will help but I dont want to take it to get a dyno tune if there is a vacuum leak or another issue going on that im missing. I have looked everything over and cant seem to find a leak, is there any ideas on something I may be missing here?

Also since the install my brake pedal has been alot easier to push than normal and seems like its not there 100%. Thanks in advance.

deelong4002

iTrader: (8)

Did you reconnect the Vacuum line for the HVAC? I almost didnt, and that would definately cause a vaccuum leak. ALso did you seal your MAP with anything. I RTV'd mine, there is no positive lock on it, like there is on the stock Manifold, and its prone to leak.

Did you torque the bolts in the correct sequence? There is a specific sequence to tightening the bolts that hold the manifold down.

wg871

iTrader: (15)

We did torque the bolts down in sequence, map sensor was sealed.. Ill check the other vacuum line too.

deelong4002

iTrader: (8)

If you find that all vaccum hoses and the Map arent leaking, you may want to let the motor get warm, and check your torque again.

I didnt have any problem with my install, but the guy i bought my intake from, said he had a hell of a time getting it to seal to the heads, and had to retorque it 3 times before it sealed properly. I also rubbed some oil on the gaskets and made sure the head surface was very clean before in installed.

I'll also assume that you changed out the coolant lines under the intake for the LS6 style?

wg871

iTrader: (15)

Yes I changed to ls6 coolant lines. I checked all the hvac line it was on. Does my brake issue sound like its related to a vacuum leak or could it be something else?

I went out and checked them all and used this diagram. Does #5 seem right? Are any of these mixed up? We have a breather on the oil cap to vent crankcase.
1. Plugged to brake booster.
2. Capped off
3. Capped off
4. Plugged in to whatever that goes to lol (I think its evap purge solenoid)
5. Hose connects it to throttle body
6. HVAC plugged in

deelong4002

iTrader: (8)

If i remember, when i get home, i'll take a look at my car. I'm at work, and cant remember if 5 is correct. Everything else seems correct as does #5 but i just cant picture it in my head.

It sounds like your leak is related to the Brake booster line, but i guess if you werent making proper vaccuum due to a leak somewhere else, that would affect all of your aux. vacuum ****.

Injectors all seated correctly?

wg871

iTrader: (15)

Injectors seem fine but ill double check. Please check 5 for me when you get home and let me know. Thanks for helping

After I rule those out im going to re torque the intake and make sure its seated good because that could be a likely possibility im missing.

deelong4002

iTrader: (8)

Yeah 5 is definately correct. Dont know man. Sounds like its just a leak some place. Dont know what else to tell you other than double check everything.

Maybe take some starting fluid and spray it around the top of the intake while running, and at least that will give you an idea of where the leak is. Just be careful, and do it with the engine cool. I hate doing it, but sometimes it helps locate a leak

good luck

bronx_peanut

I would check your IAC motor to make sure it is functioning properly. Mine wasn't working and it caused it to idle really high.

SweetS10V8

iTrader: (4)

Did you replace your valley pan bolts?? It doesnt look like it from you picture, just under your "#1" label.

You might have broken your intake if you didnt put in th correct valley plate bolts beore installing it.

wytry

iTrader: (6)

How is your PCV system routed? You have the intake manifold port for the PCV capped off, as well as the valve cover ports, except the TB one. Just wondering how it's set up...