Need to reduce idle speed
Thread Starter
Instructor
Joined: Oct 2010
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Need to reduce idle speed
I've got a thread in another sub-forum regarding a vacuum leak and the resultant high idle (1650 rpm) and here's my problem, I'm moving and having the car transported and I need a way to temporarily get the idle down to a manageable speed so the driver who loads it on the transport doesn't trash it.
Any ideas? With the move I absolutely don't have the time to fix it and just need it to be able to be started and run long enough for loading/unloading.
Thanks.
Any ideas? With the move I absolutely don't have the time to fix it and just need it to be able to be started and run long enough for loading/unloading.
Thanks.
Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
well, if there is an air leak its gonna high-idle...until that leak is stopped.
You can try to unplug the IAC or force the TB plates closed...but all that takes time.
Theres no magic fix. It takes time and effort.
You can try to unplug the IAC or force the TB plates closed...but all that takes time.
Theres no magic fix. It takes time and effort.
Thread Starter
Instructor
Joined: Oct 2010
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Will give those a try. Here's the screen cap from the Datamaster session
http://screencast.com/t/UDd3DPO6zX60
I assume the IAC Pos being at 0 means it's closed as far as it can in an effort to reduce the idle speed.
http://screencast.com/t/UDd3DPO6zX60
I assume the IAC Pos being at 0 means it's closed as far as it can in an effort to reduce the idle speed.
Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
yep...and if you CAN scan then take a look at TPS during idle to confirm throttle position...if its @ .54...you got a massive air leak.
Have you looked at the easy/obvious things? brake booster hose, vac lines on plenum, PCV lines/valve ? runner bolts/gaskets?
Have you looked at the easy/obvious things? brake booster hose, vac lines on plenum, PCV lines/valve ? runner bolts/gaskets?
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Thread Starter
Instructor
Joined: Oct 2010
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I replaced the stock runners and intake with a ported intake and a set of Accel runners.
Double checked everything and I *think* I found it. The Accel runners are either a universal set (i.e. ALL TPI systems) or are pre-90.
The stock 90 runners don't have a drivers side egr runner while pre 90s do. The 90 plenum doesn't seal up the egr runner on the drivers side and what I think happened was that the passenger side egr inlet was sucking air through the drivers side runner that wasn't sealed off.
So I took a small freeze plug and deformed it a little and then drove it into the drivers side egr runner and threw a ton of the right stuff on it.
Also used the right stuff in place of the runner to plenum gaskets which were trashed in the process.
Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
yeah......
that's a good sized hole ! and would indeed be the 'massive' kinda leak I was referring to..
Hopefully it's fixed.
Good catch !
I am porting a set of SLP Siamese runners that have a single egr port. Not a big deal as long as the other side of the plenum gets sealed up.
I never considered that issue because I was going to have to make gaskets to fit mine.
See? that didn't take long. The stress of moving must be getting to you...I'm STILL in therapy after my last move...
that's a good sized hole ! and would indeed be the 'massive' kinda leak I was referring to..
Hopefully it's fixed.
Good catch !
I am porting a set of SLP Siamese runners that have a single egr port. Not a big deal as long as the other side of the plenum gets sealed up.
I never considered that issue because I was going to have to make gaskets to fit mine.
See? that didn't take long. The stress of moving must be getting to you...I'm STILL in therapy after my last move...
Last edited by leesvet; Sep 4, 2013 at 09:17 PM.
Thread Starter
Instructor
Joined: Oct 2010
Posts: 140
Likes: 0
Thread Starter
Instructor
Joined: Oct 2010
Posts: 140
Likes: 0
yeah......
that's a good sized hole ! and would indeed be the 'massive' kinda leak I was referring to..
Hopefully it's fixed.
Good catch !
I am porting a set of SLP Siamese runners that have a single egr port. Not a big deal as long as the other side of the plenum gets sealed up.
I never considered that issue because I was going to have to make gaskets to fit mine.
See? that didn't take long. The stress of moving must be getting to you...I'm STILL in therapy after my last move...
that's a good sized hole ! and would indeed be the 'massive' kinda leak I was referring to..
Hopefully it's fixed.
Good catch !
I am porting a set of SLP Siamese runners that have a single egr port. Not a big deal as long as the other side of the plenum gets sealed up.
I never considered that issue because I was going to have to make gaskets to fit mine.
See? that didn't take long. The stress of moving must be getting to you...I'm STILL in therapy after my last move...
LOL... Yeah, I can definitely sympathize with that. Plus we're going from Cali to the Southern Oregon coast so it's a bit of a haul. Bright side no more smog checks... Yeah baby, long tubes here I come...
I'm going to let the right stuff sit and seal for a good bit before I fire it up. Will let you know what happens.
Melting Slicks
Joined: May 2010
Posts: 2,082
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From: Conowingo Maryland
you do not want to use that stuff on the intake. it can suck right into the top end of the engine. Not sure about tpi but the factory runners there is a left and right. sounds like your best bet would be to pull things back appart and start over
Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
LOL... Yeah, I can definitely sympathize with that. Plus we're going from Cali to the Southern Oregon coast so it's a bit of a haul. Bright side no more smog checks... Yeah baby, long tubes here I come...
I'm going to let the right stuff sit and seal for a good bit before I fire it up. Will let you know what happens.
I'm going to let the right stuff sit and seal for a good bit before I fire it up. Will let you know what happens.
Just be forewarned, it gets hotter than lil sister in Ore...the humidity is comparable to the gulf coast...near 100% all the time.
Good luck, I'm sure its a done deal.
Thread Starter
Instructor
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There is a left and right and the difference in the accels is the EGR port on the manifold side. Definitely have those on correctly. The trip up was the extra drivers side egr port at the plenum end.
Engines got 100K on it anyway so an excuse for a 383 wouldn't break my heart...
You're gonna enjoy the scenery once you get north of Ca...the mountains up there and the forest...are no less than amazing ! I did that drive in the winter and it felt like I was driving thru a Christmas card...
Just be forewarned, it gets hotter than lil sister in Ore...the humidity is comparable to the gulf coast...near 100% all the time.
Good luck, I'm sure its a done deal.
Just be forewarned, it gets hotter than lil sister in Ore...the humidity is comparable to the gulf coast...near 100% all the time.
Good luck, I'm sure its a done deal.
Thread Starter
Instructor
Joined: Oct 2010
Posts: 140
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There's a thought. If the latest fix doesn't work I could take a sheet of rubber gasket material stretch it over the TB opening and secure it with the hose clamp off of the funnel. Maybe punch a couple of small holes in it to get some sort of throttle functionality. Basically just reduce the throttle air flow to account for the leak.