vaccum leak?

[home13oy75]

I have a RB20DET and finally got the car started again. Keep in mind the car ran great before and I had a coolant leak so I ended up removing the intake manifold ( top hat ) last FALL. Well I finally have the car started and it idled fine at first, once it warms up the idle is very low and it keeps dying.

1. Fuel pressure gauge reads 44psi w/vaccum line connected but when I try and disconnect the line there isn't a change in fuel pressure reading.

2. I hear a sucking noise near the AAC - vacuum leak?

3. Boost gauge stays at 0 and doesn't move with the car running.

4. Took it around the block and it won't rev past 3k - once the car was warmed up it kept dying on me.

There is a air pump I think on the passenger side rear firewall that has a vaccum line coming out - it connects to the rest of my vaccum lines right?

[home13oy75]

I'd like to add the car runs fine when cold. Idle is perfect. Once it warms up the idle surges for a second and then the idle drops and dies. If I try and restart it I can't.

The AAC valve has been cleaned.

[rotorimp]

I the main thermosat sender connected? If the ECU still thinks it is cold then it will be too rich and cause your problem.

[Joe]

I the main thermosat sender connected? If the ECU still thinks it is cold then it will be too rich and cause your problem.

ehh right description, wrong part. its a 2 wire connector on the top of the upper water outlet on the engine.

its the temperature sender. thermostats dont send anything. they just open or close.

the 0" of vacuum at idle troubles me.

[rotorimp]

Yep--Temp. sender

That's the one I meant!

I would have said Timing because of the Vacuum but he said that it runs fine while it is cold--so it is most likely a closed loop sensor.

[home13oy75]

I do have the temp sensors connected ( both of them ). I also do see the temp rising on the gauge cluster - so I assume at least the single wire sensor is fine. I'll see if maybe the ecu is bad. Thanks for the advice and I'll let you all know what I find out for future reference.

[Sil240]

Hey,If your Boost gauge read Vacuum also.And it read 0 (atmosphere) all the time, then it is either not hooked up correctly or it is where you have the leak.

Does anyone know how much Vacuum you should have @ idle?

Get a cigarette and blow the smoke anywhere you think you might have a leak.Wherever it gets sucked in then you know thats were the leak is.

PS. Check all your Vacuum lines, T's and connections.

[home13oy75]

That's actually a good idea. I really hope that the leak isn't a improper aligned intake manifold. It'll be a pain to get it off again.

I do hear a sucking sound around the intake manifold. It's been so long since I had the car running I can't remember it that is normal or not.

I basically have the following connections.

1. PCV (valve cover ) to intake manifold. 2. Brake booster to intake manifold. 3. BOV connected to FPR , fuel damper thing, and then there is another nipple on the back of the intake manifold that is connected to these as well. 4. On the IC piping to the IACV valve

[Rb20_POWER]

my vac. is 20 at idle..

[Sil240]

Ok cool.My boy is getting 20 at idle also.

Thanks

[home13oy75]

I figured out part of the problem. I didn't have the fuel gauge and fpr hooked into the intake manifold vaccum line. Now I get 35 psi w/ vaccum. With the boost gauge, it's electronic so maybe I have have a loose connection somewhere.

If you guys pull the vacuum line from your FPR while the car is running, does it die? I'm just trying to make sure my vacuum system is correct because I keep hearing this sucking sound by my intake manifold. I blew smoke around the area and the smoke wasn't being drawn in. My intake manifold is a top hat so maybe it does create that sound. I don't know.

[Sil240]

I have the top hat ITM also.You do hear regular engine noises.I don't know from stock, because I've never ran my motor with the stock Plenum.

What are you talking about Fuel gauge??You fuel gauge wether it be Pressure or tank, should have NOTHING to do with Vacuum lines.

PS. I need to make a bracket for my throttle cable. You have any pics of yours.I have a couple ideas that I'm kick'n around.

[home13oy75]

I'll see if I can get some pics snapped up.

Sorry I should clarify. I meant the fuel pressure gauge. When I pull the vaccum line while idling - the car studders and dies.

Do you hear a sucking noise when the car is running from the intake manifold?

[Sil240]

Yes, I do hear a lot of sucking.But I can't really tell because I have no exhaust on it.NO intercooler piping either.

What's your email I'll send you a crappy vid?

[home13oy75]

[email protected]

I'll try and get the pic for you today.

[Sil240]

Yeah bro whenever.

I just sent you the vid.Crappy vid though.It was taken on a camera phone.

Not mine because I'm still in the stone age, chillin with Fred Flinstone.