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relocated maf and now it doesn't idle well?

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Old Dec 28, 2002 | 01:08 PM
  #41  
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Default Re: relocated maf and now it doesn't idle well?

jas thanks for clearing that up! i have a fule filter ( small one) inline form the valve cover to the inlet to act as a catch can. i wounder how that is effecting things???

Black LS1 T/A, i'll definatly check that. it would explain alot of things if it was sticking.

sscamaro387, have you had your car dyno tuned?
it sounds like you have an air leak somewhere. go over the complete system with a screw driver and check if there are any clamps loose. also run your hand around both the MAF and the throttle boddy hoses to make sure that the edges are sitting flush ( i had one hose folded in at the bottom side of the throttle body once).
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Old Dec 28, 2002 | 02:02 PM
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Default Re: relocated maf and now it doesn't idle well?

Most BOV's are open when they see a vacuum source, this is how they operate. Under idle and even under some part throttle operation they are helped open by the vacuum the engine generates. It is true that some are adjustable, but I dont know about the ATI ones. To answer the question about metering the air before the engine actually uses it, correct operation of the MAF dictates MAF to throttke body. This configuration you have consists of MAF to blower to BOV and then to throttle body, there are two things between the MAF and the Throttle body now. It is highly doubtful that the blower is leaking, but the BOV is "leaking" already metered air that the engine thinks it is going to need and use. If you think long enough about it you will understand.
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Old Dec 28, 2002 | 02:22 PM
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Default Re: relocated maf and now it doesn't idle well?

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by cdk4219:
<strong> Most BOV's are open when they see a vacuum source, this is how they operate. Under idle and even under some part throttle operation they are helped open by the vacuum the engine generates. It is true that some are adjustable, but I dont know about the ATI ones. To answer the question about metering the air before the engine actually uses it, correct operation of the MAF dictates MAF to throttke body. This configuration you have consists of MAF to blower to BOV and then to throttle body, there are two things between the MAF and the Throttle body now. It is highly doubtful that the blower is leaking, but the BOV is "leaking" already metered air that the engine thinks it is going to need and use. If you think long enough about it you will understand. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">First, the BYPASS VALVE on the ATI recirculates, it does NOT vent to atmosphere. Same with the VORTECH LS1 SC setup. Yeah, ATI could of designed it with vent to atmosphere since the MAF is before the TB in a stock ATI setup, but they didn't. Instead they gave us a bypass valve on ONE side after the intercooler that recirculates. Packaging space????

Second, LOOK at a Vortech setup, it is a pull through system. The MAF is BEFORE the blower and they don't have issues.

I would still like for you to explain this "leak" at the bypass valve????
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Old Dec 28, 2002 | 02:41 PM
  #44  
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Default Re: relocated maf and now it doesn't idle well?

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by 1dirtyZ:
<strong>
sscamaro387, have you had your car dyno tuned?
it sounds like you have an air leak somewhere. go over the complete system with a screw driver and check if there are any clamps loose. also run your hand around both the MAF and the throttle boddy hoses to make sure that the edges are sitting flush ( i had one hose folded in at the bottom side of the throttle body once). </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">ya, car has been dyno tuned, and after I drove home from Sacramento(200 mi. or so) let it sit for 5hrs, then later that nite I wanted to go to the streetraces to feel the power. and the SES light came on. everythinjg should be good, cause it was fine b4 i got it tuned. So I think it has to do with it, But i will check all the things u mention.

Thankx
dirtyz
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Old Dec 28, 2002 | 04:11 PM
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Default Re: relocated maf and now it doesn't idle well?

see that's what i can't figure out, the stock ATI setup where the maf is after the blower and just before the throttle body seems to be the most logical and practical since yuo are only metering the air the engine needs. the problem with that is the car has a wierd dead spot just as you tip in the gas and your Ltrims are always positive no matter what i tried to do.

no on the other hand putting the maf before the blower introduces other variables like you mentioned ( breather hose and bov) BUT the car drives like it has no blower ! very smooth throttle responce and no jerkyness, just the dying issue.

i was a strong opposer to the before blower maf place ment method cause it made no sence to me. but after i tried relocating the maf i became a beliver! it doesn't make perfect sence , but it seems to be working fine.

i almost forgot, i checked the bov and it operated very smoothly.

i also noticed the adjustment screw on the BOV, what does that do???
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Old Dec 28, 2002 | 07:59 PM
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Default Re: relocated maf and now it doesn't idle well?

I dont know what to tell you JAS but good luck with your bad idle and stalling.
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Old Dec 28, 2002 | 11:39 PM
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Default Re: relocated maf and now it doesn't idle well?

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by cdk4219:
<strong> I dont know what to tell you JAS but good luck with your bad idle and stalling. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">You know what, I have a STOCK SMOOTH idle and no stalling, so I don't know what the heck some of these guys are doing except for the fact that some don't have a PCV system or idle below stock with large cams, etc... etc..

I still would like for you to explain to me how you think a recirculating BYPASS VALVE leaks to atmosphere however???
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Old Dec 29, 2002 | 12:29 AM
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Default Re: relocated maf and now it doesn't idle well?

I m having problems when it dies also. but it mostly just drops down to 400 rpm, and back up to idle,then 400 rpm, then idle. does it couple of times at a stop. Also I m throwning lean codes. P0147, and P0141(Atap codes). said it was running lean on Bank1 and Bank2. So i cleared them, they came back after a couple days. So I leave it on. And after a couple of days, it goes off. But it still surges/dies, with/without the SES light on.

Edit- My MAF is stock, and right B4 the TB.
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Old Dec 29, 2002 | 01:23 AM
  #49  
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Default Re: relocated maf and now it doesn't idle well?

jas , you still have the pcv system hooked up right?? and you have the stock ATI maf location?
would you mind if i asked what your cam specs are?

i tried raising the idle but it didn't help.
<img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" />


i just set a ses light and i'm hoping it's either the IAC or tps sensors ( it would explain alot!)
tonight the car started to get less drivable, just as you tip in the gas the rpm shoot DOWN!!! just like shutting the ignition off. so i'm hopeing it's one of those two sensors.
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Old Dec 29, 2002 | 01:43 AM
  #50  
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Default Re: relocated maf and now it doesn't idle well?

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by cdk4219:
<strong> I dont know what to tell you JAS but good luck with your bad idle and stalling. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Let's not answer hard questions with sarcastic or glib comments. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> That's how quarrels get started.

Let's just keep talking about and figure it out.
I DO have a big cam and I DO like the idle low, so I get some lope. I don't have a narrow LSA and a low idle gives it some funk. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> I upped it back to 800 RPMs and haven't experienced the stumble again, yet. I also haven't seen the Purge Valve stick anymore.I don't know what's up with that.

I hope we can ask each other hard questions and when they are critiqued, we can come back with some rationale or explanation or a simple, "I don't know". <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
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Old Dec 29, 2002 | 01:50 PM
  #51  
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Default Re: relocated maf and now it doesn't idle well?

Mike,

How did you like your PY3400 converter? I was looking at the PY3600E converter. Was your converter really tight? Just curious. I'm looking for a blower converter for my future plans. Thanks.

Den
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Old Dec 29, 2002 | 02:02 PM
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Default Re: relocated maf and now it doesn't idle well?

<img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" /> <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" /> <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" /> <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" /> <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" /> <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" /> <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" /> <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" />
as you all know i had some wired drivability problems last night i.e. won't idle well , would die at tip in , etc,etc. so i take the maf off and put it in the stock location .
i take the car out and it drives like a dream!!! WTF!!!! why was it doing all that stuff before!??

some one please shoot me! i'll be at the wall banging my head!
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Old Dec 29, 2002 | 07:14 PM
  #53  
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Default Re: relocated maf and now it doesn't idle well?

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by 1dirtyZ:
<strong> <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" /> <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" /> <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" /> <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" /> <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" /> <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" /> <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" /> <img border="0" alt="[bang head]" title="" src="graemlins/gr_banghead.gif" />

some one please shoot me! i'll be at the wall banging my head! </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Hey I'll join ya, cause I tried to find an intake leak,thought it might be the catch can..... but nothing. I also changed the PCV valve, to the one with a pin size opening. I also got that MAF translator from T-byrne. It should be here tuesday.

Also I haven't thrown any more Codes. But it it still is dying/surging at stops. have anybody figured out what the problem is?
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Old Dec 29, 2002 | 09:34 PM
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Default Re: relocated maf and now it doesn't idle well?

The air that BOV pushes back into the area between the MAF and the blower inlet will need to displace some of the air that has already entered through the MAF. When you close the throttle body all this stuff happens and the MAF will actually read some of the air twice before it reaches the engine, because it actually pushes or displaces that air back the wrong way. Sounds silly, but with the finicky nature of the LS1 MAF it could be a problem. JAS you are right with it not being a problem with idling.
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Old Dec 29, 2002 | 10:31 PM
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Default Re: relocated maf and now it doesn't idle well?

Ok lets stop for a sec. and 1DirtyZ's car, he has it before the blower.

I on the other hand, have a stock MAF, right b4 the TB, So all the air going in the engine, IS metered air.

So my setup is like this.

Filter--Blower--Intercoolers--Airbox--MAF--TB--and u know the rest.

And I guess 1DirtyZ has his setup like this.

Filter--MAF--Blower--Intercoolers--Airbox--TB--and the rest u know.

So doesn't it have to be something else contributing this problem?
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Old Dec 30, 2002 | 05:17 AM
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Default Re: relocated maf and now it doesn't idle well?

ok, here it is , after many a head bangs at the wall!

it's either the iac motor going bad. or a combo of tps and iac going bad.

or it's the maf NOT metering air ( actually regestering zero flow) because the air is circulating in a circular path ( blower--> bov--> inlet hat --> blower--> bov ....) due to the throttle blade being shut. but this is unlikely..

or it could be the bov valve flowing air out of the maf (reversing the air flow) and causing a surege ...

or ( most likely) its a combo of maf location and the fule delivery being waaaay off. i noticed that the Ltrims where always positive with maf in the stock location no matter what i do. but after i relocate the maf i get a hold of controlling the Ltrims, and i had to richen up the car quite a bit to get them where i need to. so now after i returned the maf to the stock location it drives better because of that.

now i know this sounds shady, but give it a try; re locate the maf to preblower , adjust Ltrims then re-relocate the maf to the stock location.

now as far as sscamaro387 is concerned , we need some more constructive wall banging to solve this. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
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Old Dec 30, 2002 | 05:43 AM
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Default Re: relocated maf and now it doesn't idle well?

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by 02BlackWS6:
<strong> Mike,

How did you like your PY3400 converter? I was looking at the PY3600E converter. Was your converter really tight? Just curious. I'm looking for a blower converter for my future plans. Thanks.

Den </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Sorry I haven't been reading/answering these posts promptly. I'm out of town with my parents... dad just got out of the hospital with heart related problems.

The PY3400 is great! The STR is higher, so it pulls harder than the SY3500... plus they build it with the 422 and blower in mind. With sticky tires, I get a decent hook-up, considering the torque and power I've got. I can STILL forget WOT takeoffs on the street, especially with street tires.

As for driveability, it doesn't have as much slop as the SY3500. As a matter of fact, I barely feel the stall until I'm at WOT... then, at WOT, I barely see below 5000 RPMs again... maybe 4800 or so, if I've got a good hookup.

Since I had the SY3500, I had a conversion done to it for a PY3400. I wish I could have gotten the PY3400Extreme. The difference is, the PY3400E has the guts to let you lock up the converter under WOT... the PY3400 doesn't have the ***** for that. <img border="0" title="" alt="[Frown]" src="gr_sad.gif" />
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Old Dec 30, 2002 | 05:54 AM
  #58  
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Default Re: relocated maf and now it doesn't idle well?

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by sscamaro387:
<strong> Ok lets stop for a sec. and 1DirtyZ's car, he has it before the blower.

I on the other hand, have a stock MAF, right b4 the TB, So all the air going in the engine, IS metered air.

So my setup is like this.

Filter--Blower--Intercoolers--Airbox--MAF--TB--and u know the rest.

And I guess 1DirtyZ has his setup like this.

Filter--MAF--Blower--Intercoolers--Airbox--TB--and the rest u know.

So doesn't it have to be something else contributing this problem? </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">I believe the reason it is being said the stock MAF position for the ATI setup has unmetered air is because the hose that goes from the inlet hat to the top of the valve cover looks like a leak as far as metered air is concern. This air going to the motor is unmetered becuase it bypasses the MAF in the stock, after SC position. This air is simply not being measured and calculated for in the stock MAF position with the ATI setup.

Correct me, if I'm wong JAS.

When the MAF is placed in the BEFORE SC position, the MAF is now reading ALL air that enters the motor no matter how it is diverted or split up now (as long as you have no true air leaks).

Make sense?
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Old Dec 30, 2002 | 10:40 AM
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Default Re: relocated maf and now it doesn't idle well?

Mike,

Hope you dad is feeling better. Thanks for writing back. I looked on Yanks web site the PY3400E and PY3600E both look pretty sweet. Only the Py3600E has a STR of 2.3 instead of 2.7. Which is still pretty strong all things considering. Decissions, decissions <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
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Old Dec 30, 2002 | 06:54 PM
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Default Re: relocated maf and now it doesn't idle well?

hope your dad is doing well!
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