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Discussion Starter · #1 ·
The IAC is routed right. It just dies when coming to a rolling stop even if i didnt build any boost. You know the story. I have the ssqv bov. I didnt really find any real anwser from searching. And yes i know it has been covered a million times. Will rerouting my ssqv to the intake fix this? I DO NOT want to go map ecu or vpc for awhile. And yes i know that would fix this.
 

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feeding your habit
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if you are venting your BOV to atmosphere instead of back into the intake (behind the MAF) you will stall.

-M
 

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(overspooled)
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I think there is a recirc kit, but in all honesty you may want to look at options for getting rid of the maf...otherwise you'll just remove the recirc kit later when you do...
 

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Discussion Starter · #6 · (Edited)
Well i ordered the kit. Its only 12 bucks so it wont matter about not using it later.
I am just worried because alot of people still stall even after doing this...
 

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Alpine Hardtopper
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I've read a lot about this problem as well. In fact, I think there was a post just yesterday about this same situation. In their case the idle was just set WAY too low.

One way to test this would be to disconnect (and plug) the small line going to the SSQV and see if there's any improvement. Based on what you said (dies even if not building boost and rolls to a stop) I don't think the BOV is your problem.

You may want to check out the dashpot on your throttle. It's responsible for making sure the throttle doesn't close too quickly. If it's bad, you can have lots of stalling problems. Also, what is your idle speed at currently? It may not hurt to check for vacuum leaks post MAF as well. They're likely to be post throttle as well if there's air getting past when the throttle shuts. There's a lot of short vacuum lines on the manifold that can get bumped and crack when switching to a single.

Did you use/cap off the hard vacuum line that runs behind the engine? It's right by the coolant line...above where the two lines are for the vacuum tank.

For what it's worth, I went with a small single and am using the MAF still. Idle is no different than with the twins. It did die on me once in the first week of driving, but I wonder if the ECU hasn't addapted some since it's never done it since.
 

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Discussion Starter · #8 ·
cord4530 said:
I've read a lot about this problem as well. In fact, I think there was a post just yesterday about this same situation. In their case the idle was just set WAY too low.

One way to test this would be to disconnect (and plug) the small line going to the SSQV and see if there's any improvement. Based on what you said (dies even if not building boost and rolls to a stop) I don't think the BOV is your problem.

You may want to check out the dashpot on your throttle. It's responsible for making sure the throttle doesn't close too quickly. If it's bad, you can have lots of stalling problems. Also, what is your idle speed at currently? It may not hurt to check for vacuum leaks post MAF as well. They're likely to be post throttle as well if there's air getting past when the throttle shuts. There's a lot of short vacuum lines on the manifold that can get bumped and crack when switching to a single.

Did you use/cap off the hard vacuum line that runs behind the engine? It's right by the coolant line...above where the two lines are for the vacuum tank.

For what it's worth, I went with a small single and am using the MAF still. Idle is no different than with the twins. It did die on me once in the first week of driving, but I wonder if the ECU hasn't addapted some since it's never done it since.
Are you venting to the atmosphere? Where is the dashpot and what is it?
 

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Alpine Hardtopper
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Sorry...I should have been more descriptive.

When I was stock twins, my SSQV vented to atmosphere and was fine. But when I went single I installed a bypass kit (Think I got mine from Horsepower Freaks...can't remember for sure). I'm waiting for some time to install/tune my AEM, but in the mean time, the MAF has worked great.

The dashpot is on the passenger side of the throttle body. It's a small round thing (maybe 1.5" in diameter) that the throttle linkage hits against just before it closes. It should offer resistance to movement. If yours is missing, or doesn't slow the throttle down when it is closing, then this may be your problem. For a image of my engine bay (forgive the 250 mb size) with the dashpot highlited, see here:
http://www.its2.uidaho.edu/cordon/dan/automotive/Cars/Supra_Images/Supra_dashpot.jpg
You can also see the BOV routing as well.

In my next incarnation, I'm hoping to have one of the new T67 DBB turbos and route the IC piping down low and out of the way. Oh ya...and moving the BOV to the other side of the IC and no MAF, and.....
 

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Canadian monster
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i had the same problem as you, i didn't even run a wastegate and it still did it, not even going into boost.

I even tried to put a stock BOV and route it back from the intercooler piping to the intake pipe and it still did it. I had no other choice but to go vpc. Since then, other than the fact i got a bad vpc chip, the car runs like a champ.
 

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Discussion Starter · #11 ·
so then is it pointless that i ordered the recirc kit for my bov? Is this not going to fix it? It seems to fix it on some cars and not on others.
 

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Alpine Hardtopper
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No not pointless at all. If you're going to run MAF for a while, you probably should re-route the metered air back in to the turbo inlet. Even if the recirc kit doesn't fix your problem, it is going to help. There may be a completely different problem that's causing the stalling. If you were to fix *that* problem, then not having the BOV recirculating could still give you fits.

Did you ever say what your normal idle was at? If it was low, trying to increase the idle speed may help. However, idle speed is controlled by the ECU and could be hard/impossible to adjust.
 

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Canadian monster
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i put my idle at 1100 rpm and i still had the stalling issue he has.

i suppose it does it when you come to a stop and push the clutch? the other way is to live with it and learn to drive it a different way, you just need to push on the clutch at the last second before the car comes to a stop.
 

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Discussion Starter · #15 ·
puma said:
i put my idle at 1100 rpm and i still had the stalling issue he has.

i suppose it does it when you come to a stop and push the clutch? the other way is to live with it and learn to drive it a different way, you just need to push on the clutch at the last second before the car comes to a stop.
yeah i have figured out how to drive it...just annoying.
 
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