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Old 04-15-2012   #1
XfireZ51
 
Join Date: May 2007
Location: Chicagoland, IL
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Default Riddle me this Batman

Got the motor put together and am battling what appears to be a vacuum leak. I first addressed what appeared to be an issue with a sticking throttle. Took primary throttle apart and cleaned off shaft of any "paint" and re-installed throttle blade. Took car out for drive and it actually didn't behave badly but idle speed was a bit high. However the "cruise control" sticking throttle seemed to be fixed. However, I still have what feels like a vacuum leak. Pulled the PCV and the 2 side ports of the plenum. In each case, idle would INCREASE when I exposed them to atmosphere.
My concern is a leak at the throttle body somewhere. It tends to raise idle from 825 commanded to a 975-1000 actual.
Here's what is interesting. when I first start the motor it will "flare" to 1500-1700rpm then idle will drop to 1000 w coolant temps at 50C.
As coolant temp increase I can see the IAC counts drop and so does the idle rpm. OK, so now the motor is idling at about 850 or so with IAC counts of ~ 10. GREAT except then I blip the throttle. IaC counts drop to 0 and now idle has a bit if a surge at about 900-1000. Otherwise the car drives well with no surging at PT cruise. So why does blipping the throttle
upset the apple cart?? Any suggestions before I pull the plenum are appreciated.
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Old 04-15-2012   #2
John Boothby
 
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Default Re: Riddle me this Batman

Just a guess, but did you check your TPS?
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Old 04-15-2012   #3
XfireZ51
 
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Default Re: Riddle me this Batman

Quote:
Originally Posted by John Boothby View Post
Just a guess, but did you check your TPS?
.55v. I put a scantool on it, yes.
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Old 04-15-2012   #4
rhipsher
 
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Default Re: Riddle me this Batman

Dom after I had my top end powdercoated and put it back together I had a high idle problem. And when id blip the gas peddle the idle would drop back down to normal 900. This is a vid I made of the problem and how I fixed it.
http://static.photobucket.com/player...-04-26_724.mp4
Im not saying this is the cause of your problem but its worth taking a look at.
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Old 04-15-2012   #5
XfireZ51
 
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Default Re: Riddle me this Batman

Quote:
Originally Posted by rhipsher View Post
Dom after I had my top end powdercoated and put it back together I had a high idle problem. And when id blip the gas peddle the idle would drop back down to normal 900. This is a vid I made of the problem and how I fixed it.
http://static.photobucket.com/player...-04-26_724.mp4
Im not saying this is the cause of your problem but its worth taking a look at.
Would love to see vid. Link not working.
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Old 04-15-2012   #6
RICHARD TILL
 
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Default Re: Riddle me this Batman

try again. i just watched it.
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Old 04-15-2012   #7
scottfab
 
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Default Re: Riddle me this Batman

Video worked for me. Well done.
I have not seen sticking there before but will keep it in mind.
What I have seen on two TBs is the big two sticking.
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Old 04-16-2012   #8
rhipsher
 
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Default Re: Riddle me this Batman

Were you able to veiw the vid Dom? I don't know how else to get it to where you can veiw it. But in a nutshell the little lever outside the TB housing on the drivers side that opens the primary throttle plate was sticking open from lack of lubrication. Hitting it with brake clean and then white lithium made it operate smoothly.
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Old 04-16-2012   #9
GOLDCYLON
 
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Default Re: Riddle me this Batman

Dom I could send you back your old TB you sold me a year ago to test out your TB theory. Its just sitting in the parts crib. LMK Daryll
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91 WHITE/BLACK #2014. 380 P&P&PCed,Ported Heads, Jeal Long tubes, Corsa Exhaust/FIKSE FM-5s /LED TLs, LED Headlights, Front Wilwood 6 piston narrowlite calipers and rear Wilwood caliper street shop mod,CNCed Coolant Pipes,TPI Cvr,Filter cover,Stainless Bolts, DRM/DOM PROM /ZFDOC mod build #102,DRLs,BMAD with stainless Debris Screen,Coplan Air Blaster, Pioneer APP Radio 4,Brey-Krause HB,Sub Bar,Fire extinguisher seat mount,DRM Coilovers,LEDs everywhere,Compass mirror (orange),V1 DIC hidden display, Homelink sun visor, Carbon Fiber top x3 and APSIS Carbon Fiber interior, APSIS CF Steering Wheel/NAPA Leather, Banski trailing arms, Guldstrand front suspension,urethane bushings from Prothane (total suspension) ZFDoc drive shaft safety loop, raptor shift light (orange),AO engineering louver front plate, Console seat cushion, 96CE seats with black custom Sheepskins, ss billet catch can,Viper remote entry/alarm,Cragar Rear Louvers,LED side louver lights, Dewitts Radiator with SPAL fans and a Woods 160 T-Stat

90 RED/BLACK #2794. 4L60e Automatic Stage V by RPM Transmission, TCI Dedicated TCM, OBX Stainless Headers, Corsa Exhaust, SAN Secondaries and Haibeck PROM, Exotic Muscle Coil overs, LED Interior Lights, LED Tail Lights, LED Headlights, 94 Sport seats with black custom Sheepskins , Cragar rear louvers, GS Front calipers, Banski Trailing arms, APSIS Carbon Fiber steering wheel, Front and Rear Baer Eradispeeds, DRLs, Guldstrand front suspension,urethane bushings from Prothane (total suspension), Dewitt's Raditor with Dual SPAL fans and a Haibeck 170 T-Stat

11 RED/GREY CTS-V
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Old 04-16-2012   #10
GOLDCYLON
 
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Default Re: Riddle me this Batman

Quote:
Originally Posted by rhipsher View Post
Were you able to veiw the vid Dom? I don't know how else to get it to where you can veiw it. But in a nutshell the little lever outside the TB housing on the drivers side that opens the primary throttle plate was sticking open from lack of lubrication. Hitting it with brake clean and then white lithium made it operate smoothly.

Good video. Last time I had a simular problem the IAC valve on the oposite side had seperated inside the side of the AH. The spring and the check valve had seperated from the valve body and were sucked into the side of the AH. Just another possibility.
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91 WHITE/BLACK #2014. 380 P&P&PCed,Ported Heads, Jeal Long tubes, Corsa Exhaust/FIKSE FM-5s /LED TLs, LED Headlights, Front Wilwood 6 piston narrowlite calipers and rear Wilwood caliper street shop mod,CNCed Coolant Pipes,TPI Cvr,Filter cover,Stainless Bolts, DRM/DOM PROM /ZFDOC mod build #102,DRLs,BMAD with stainless Debris Screen,Coplan Air Blaster, Pioneer APP Radio 4,Brey-Krause HB,Sub Bar,Fire extinguisher seat mount,DRM Coilovers,LEDs everywhere,Compass mirror (orange),V1 DIC hidden display, Homelink sun visor, Carbon Fiber top x3 and APSIS Carbon Fiber interior, APSIS CF Steering Wheel/NAPA Leather, Banski trailing arms, Guldstrand front suspension,urethane bushings from Prothane (total suspension) ZFDoc drive shaft safety loop, raptor shift light (orange),AO engineering louver front plate, Console seat cushion, 96CE seats with black custom Sheepskins, ss billet catch can,Viper remote entry/alarm,Cragar Rear Louvers,LED side louver lights, Dewitts Radiator with SPAL fans and a Woods 160 T-Stat

90 RED/BLACK #2794. 4L60e Automatic Stage V by RPM Transmission, TCI Dedicated TCM, OBX Stainless Headers, Corsa Exhaust, SAN Secondaries and Haibeck PROM, Exotic Muscle Coil overs, LED Interior Lights, LED Tail Lights, LED Headlights, 94 Sport seats with black custom Sheepskins , Cragar rear louvers, GS Front calipers, Banski Trailing arms, APSIS Carbon Fiber steering wheel, Front and Rear Baer Eradispeeds, DRLs, Guldstrand front suspension,urethane bushings from Prothane (total suspension), Dewitt's Raditor with Dual SPAL fans and a Haibeck 170 T-Stat

11 RED/GREY CTS-V
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