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low boost transition problem.

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Old 06-29-02, 03:30 PM
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low boost transition problem.

I'm gettin some low transition on my turbos. the 3rd gear boost test gives me 10-5-12. If I do it in 1st gear I get 10-5-slowwly creeps up until it hits 7 at red line.

I have a pre-spool valve thats opened alot and and its sitll only 5 for the transtition.

any help people?
Old 07-01-02, 10:25 AM
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I ahve a lil mroe info with my problem. When I do the 3rd gear test. I get the low transition, but right after that I also get the boost spike.

Does this help any?
Old 07-01-02, 05:30 PM
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really no one can help me? not even give me a starting point?
Old 07-02-02, 01:26 AM
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i also have the same problem no matter how much I open up the precontrol valve I still get a big *** dip during transition...maybe I should just pop back the stock precontrol line...

some forum members have suggested me to turn up the duty % on the pfc a little...but that didn't do anything ...

anyone??
Old 07-12-02, 06:13 PM
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any other thoughts on this people? PLease!! my car is so slow now, in first gear secondary boost doens't even climb fast enough to get to 10 before redline.
Old 07-14-02, 03:13 PM
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anyone? at least tell me where to start looking.
Old 07-15-02, 11:28 AM
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So what are your mods? Do you have stock pills? Boost controller? ECU? I got the same problem when I added a SMIC and reprogrammed ecu to my car.

What did you change just prior to the problem starting. Some more history is needed to help you with this.

Jeff
Old 07-15-02, 11:50 AM
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I just noticed the same problem with my car on a trip to northern california and lake tahoe. I thought it was an altitude issue, but nope.

I installed the powerFC approx. 1 month ago. and only recently started having these same problems. Also recently started having the A/C Idle fluxuation issues.

I'm running the base maps with no tuning.

There was a huge boost issues thread a while back, and looked like this odd transisiton/boost leak with spiking was due to a faulty TCV unit but there was no straightforward answer.

I'm assuming there will be no "quick fix" to this problem.. it seems to be plaguing multiple people.

I'm going to be taking my car to my mechanic sometime this week to diagnose the problem.

My mods:

PowerFC
Downpipe
Catback Exaust

other additions:

Koyo Radiator
JIC coilovers
Old 07-15-02, 04:41 PM
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Originally posted by aReX-7
So what are your mods? Do you have stock pills? Boost controller? ECU? I got the same problem when I added a SMIC and reprogrammed ecu to my car.

What did you change just prior to the problem starting. Some more history is needed to help you with this.

Jeff
sorry, my mods are in the sig, and I'm using a precontol valve isntead of pills
Old 07-15-02, 04:53 PM
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Let's keep in mind that is you are using a valve in the precontrol line, making the oriffice larger is going to INCREASE your lag on the change over. Most people I have delt with have boost spikes onto the secondary and putting a larger hols pill helps to problem. I would make the oriffice smaller by tightening the valve. Your best bet really is to reinstall the origional pill. If the problem still exists then further investigating would be required.

Paul
www.iridiumracing.com
Old 07-15-02, 05:08 PM
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Originally posted by PaulyDee
Let's keep in mind that is you are using a valve in the precontrol line, making the oriffice larger is going to INCREASE your lag on the change over.
Paul
www.iridiumracing.com
I think you are backwards....or my car is
Old 07-15-02, 05:11 PM
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Originally posted by PaulyDee
Let's keep in mind that is you are using a valve in the precontrol line, making the oriffice larger is going to INCREASE your lag on the change over. Most people I have delt with have boost spikes onto the secondary and putting a larger hols pill helps to problem. I would make the oriffice smaller by tightening the valve. Your best bet really is to reinstall the origional pill. If the problem still exists then further investigating would be required.

Paul
www.iridiumracing.com
yeah, it goes the other way around. larger opening = larger boost spike. I've had the valve on for about a year and this problems just popped up about a month ago.
Old 07-16-02, 11:08 AM
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Zoom,

I PM'd you, but I just looked at the thread again. I didn't realize that your problem just started. And, it looks like you have a stock IC?

If this is the case, are you sure you have not changed anything just prior to the problem starting. Sometimes things that you think could never be related to a boost problem can jump up and bite you. Also, could the precontrol valve have just gotten bumped and needs to be readjusted? Maybe there is some junk in the line that is lodged at the opening to the valve. Just a thought.

What was your boost pattern before, and now?
Old 07-16-02, 12:55 PM
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Originally posted by aReX-7
Zoom,

I PM'd you, but I just looked at the thread again. I didn't realize that your problem just started. And, it looks like you have a stock IC?

If this is the case, are you sure you have not changed anything just prior to the problem starting. Sometimes things that you think could never be related to a boost problem can jump up and bite you. Also, could the precontrol valve have just gotten bumped and needs to be readjusted? Maybe there is some junk in the line that is lodged at the opening to the valve. Just a thought.

What was your boost pattern before, and now?
I've already adjusted the valve alot, I belive its almost all the way open, I'll take it off sometime when I get a chance.

Before my boost pattern was 12-10-12.
Old 07-16-02, 02:12 PM
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Check your one way valves and make sure the turbo control is getting pressure on one side and vacuum on the other.

Wade
Old 07-16-02, 05:31 PM
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Originally posted by Wade
Check your one way valves and make sure the turbo control is getting pressure on one side and vacuum on the other.

Wade
where are the valves and how do I check them?
Old 07-17-02, 06:40 PM
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big red ... looks like your cat is clogged ...

mine did with the pfc, dp, and catback...ran too rich with the base map

got a mp not too long ago and it basically fixed the low transitional problem and make my car a whole lot faster.
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