surging like crazy?! Input needed on trouble shooting

BlkCurrantKord

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As annoying as it sounds, you have to let the car run to let the air bubble escape. Take off the radiator cap and let it run.
 

Theory208

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I'm gunna hold out till that gasket gets in tomarrow, and try to get the idle down enough to safely warm up to bleed.

I did some searching around, and come to find out that the tps is pretty fragile and easily damaged. That'll be my next check after the gasket and coolant bleed. Tas has a tps replacement for 50$ as opposed to buying the whole throttle body for 300$. I may just have to call the fearless, but that's the very last resort.
 

Fuzz

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An "Air Bubble" in your coolant won't cause the engine to rev to 3000 rpm.

Basically what is happening is you have a HUGE Vac Leak. Take off your intake tube from the throttle body, and block the TB off with your hand, your car should die.

If it DOESN'T DIE, then it means there is a leak. Normally the size of the leak needed to rev the engine to 3k is the intake manifold gasket... did you change that??

DO NOT PUT OTHER OBJECTS TO BLOCK THE TB. Use your hand. If you have small hands find someone with large hands.
 

Theory208

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^ yeah I changed the gaskets on the plenum, tb and the one to the head. All was cleaned and torqued to spec.
Torque specs said 16 lbs on both plenum and head.

The only gasket I re-used was the iacv. I ordered one and will have it tomarrow to change. Vac leak is what I suspected also, but why it's jumping to 3k is beyond me.
I'm gunna put on the gasket tomarrow and see if it changes anything.

Thing is, I took the plenum back off today cause if I don't use a torque wrench, with out a doubt, I'll strip the threads. In the process of taking off the coolant hose, I smacked the tps on the back of the fire wall on accident. It hit so hard I wouldn't doubt if it's broke... just another variable I might have to now look out for.

I'm so pissed I'm pretending I don't even own a car.
 
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Fuzz

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The reason the car is jumping to 3k is because its getting ALL the air it needs to rev that might because of the Vac Leak.

There is no restriction. Your TB, the IACV, Its doesn't matter because its leaking after it. Also your engine is going to be running supid lean because the car is only dumping enough fuel for 1000, and is unknowningly getting too much air. Also if you did a Vac Test with a gauge it would still show normal because of the nature of the leak.

Like I said, try changing the gaskets and then blocking the TB off with your hand and see if the car stalls. All the air the engine breaths goes through the TB housing.
 

Theory208

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Replaced the iacv gasket, idle is down to 1.5k revving to 2.5k about every 1-2 seconds (with idle screw backed out).
Rpms hold at 1.5k for about 4 seconds before it starts jumping to 2.5k.

I checked the iacv by starting engine, plugged the hole in throttle body with thumb. That dropped the rpms down to about 100 but no stall. With my thumb kept on the hole, the rpms went up to 800-900 and held steady there.

Then I let it get back up to 1.5k and then plugged entire tb with hand. It took a few seconds to stall. I kept my hand on the tb, and heard a hissing noise near the head.

I'm wondering if I have a leak where the runners meet the head. I have no problem taking the whole manifold back off (I can take it off in about 45min, 45min to re-install).

Thanks for the tips so far everyone, it'll get running again
 
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Fuzz

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That hissing is your vac leak right there :)

Chances are the gasket didn't seat properly or some debris got in the way.

Goodluck!
 

Theory208

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^That's what I'm thinking, I'm taking it back off to check. Might as well take some pictures while I'm at it.

Thanks again everyone for the tips and advice.
 
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