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Idle problem, 99 head, ms1, exploding freeze plug

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Old 10-27-2011, 02:12 PM
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Default Idle problem, 99 head, ms1, exploding freeze plug

My idle was at 2000 rpm's and when adjusting everything in MS we couldn't get it to drop (AFR was approx 15:1). We were thinking it was a vacuum leak but couldn't find one. It has MS1, a 99 head, 99 intake manifold, 99 tb with iacv, and a 94 block.

I went through and capped off all of the nipples not being used (even the one under the intake manifold) with new caps and zip tied them on prior to running. The IACV is not hooked up. The idle adjust screw has been screwed most of the way into the tb. The only things that are hooked to vacuum ports are: brake booster, ms + pressure ref for boost meter, and the diverter. Te diverter is completely shut at idle and the reading on the boost/vac meter was 20" Lastly the egr port with the top and bottom openings is plugged.

Anybody have any ideas as to what I should check?
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Old 10-27-2011, 02:22 PM
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is the idle valve dead? pull off the inlet while idling and block it with your hand. does it now stall?
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Old 10-27-2011, 04:14 PM
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It is a 99 iacv so the inlet is internal. We were thinking that it could be messing with the idle if it went open/partially open when disconnected but that may not be the case at all.
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Old 10-27-2011, 07:28 PM
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Check for leaks at the IM flange and injectors. If you still can't find it, smoke test the manifold - you have leaks somewhere.
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Old 10-27-2011, 07:32 PM
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Smoke test...would that consist of blowing smoke and seeing where it gets sucked in? I have never herd of it before.
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Old 10-27-2011, 07:45 PM
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Your explosion was epic. (no homo) Wish we got it on video.

You have a leak somewhere. The timing was smooth, the map was smooth, and even as i continued to feed it fuel (to get it closer to about 14:1) it still just sat at like 2200 rpm.

I'm bummed the car is down. I really wanted to get you a decent base tune and get that thing drivable.
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Old 10-27-2011, 07:45 PM
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FYI his vacuum was about 35 KPA
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Old 10-27-2011, 08:32 PM
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I'll be making the block off plate tomorrow so I should be good for finding the leak this weekend if I can find the time.
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Old 11-13-2011, 08:04 PM
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Made an adapter for the ic piping to hook a compressor up where the turbo would normally go and found a few problems (only went to ~10psi).

1. Couldn't tighten my greddy diverter enough make it not wheeze
2. Couldn't adjust the idle adjustment screw (I could only turn it about 1/4 of a turn)
3. With the tb open or closed I saw the same amount of air coming out of the back of the intake manifold
4. I had air coming out of the back of the intake manifold (was coming out between the egr blockoff plate and manifold from the same spot regardless of orientation of the metal gasket and the blockoff plate [I tried every combo I could])

I recon I'll be taking apart the diverter to see what is inhibiting it sealing, taking the tb off, and coming up with the solution to the leaky egr blockoff plate.
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Old 11-14-2011, 08:19 PM
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So went up to 15psi and got the egr port sealed off, checked out the greddy (leak is pretty healthy and happens with the signal line hooked up and disconnected so I'm going to have to take it apart and find the cause), got a small amount more adjustment out of the idle adjustment screw, and got some unexpected noise.

There was bubbling noise coming from the oil system. When I disconnected the catch can lines/removed the oil fill cap it would stop bubblin' and release the air. Would that be due to timing or what?
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Old 11-14-2011, 08:25 PM
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Originally Posted by astroboy
So went up to 15psi and got the egr port sealed off, checked out the greddy (leak is pretty healthy and happens with the signal line hooked up and disconnected so I'm going to have to take it apart and find the cause), got a small amount more adjustment out of the idle adjustment screw, and got some unexpected noise.

There was bubbling noise coming from the oil system. When I disconnected the catch can lines/removed the oil fill cap it would stop bubblin' and release the air. Would that be due to timing or what?
sounds like you are glogged in the PCV area. did you drill out the PCV valve? how is the catch can hooked up?
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Old 11-14-2011, 08:31 PM
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My catch can may be clogged or something, I just didn't think there should be so much blow by. I was hoping it could be something about the timing that was allowing it.
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Old 11-14-2011, 10:06 PM
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not really sure, but I was told if the catch can is sealed, you could blow out the front/rear main seals in a very short time. I am hesitant to repeat it, but <2 miles of driving...Not sure how much I believe that.
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Old 11-14-2011, 11:00 PM
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Lucky for me this is with a compressor and low pressure (with exception to when I did 15psi today for the sake of seeing what else may leak) to find the problem areas but I am feeling cautious now :(
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