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strange vacuum problem

  • Thread starter Thread starter chris642
  • Start date Start date Oct 31, 2007
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chris642

New Member
Aug 31, 2007
3
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Oct 31, 2007
#1
  • Oct 31, 2007
  • #1
I have been having some annoying problem with my 02 GT with a vortech runnin 6 PSI. the first thing i did when i got the car was put a vacuum/boost gauge on it, when i did it worked perfectly 21 HG and read the boost as it should. Then im a dumbass and think how cool it would be to have a blowoff valve so i buy one and throw it on not understanding the location of the MAF and how it wont work without a blowthrough setup. So anyway the car, of course, ran funny and wouldnt idle right and would stall on occasion. the vacuum also droped to 15 HG. So i then put the bypass valve back on to correct the problem and it did nothing but let the car run correctly and such, no stalling. The problem is the vacuum is still at 15 HG and now it says its not making booost! when i floor it the meter goes to 0 and may read like 1 PSI, idk its to hard for me to see when flooring it. I even went so far as to get a new bypass valve thinking maybe i messed up the other one taking it out or something, but it did nothing. I checked everything and its all tight, no leaks as far as i can see. i checked all the vacuum hoses and they look good and connected corectly. If there was a vacuum leak it wouldnt run right, correct? is my gauge messed up? i cant really tell if theres a power loss becasue when i got the car the tires were bald and all they would so is spin. WTF did i mess up? haha. any help would be great!
 

the98stang

Active Member
Aug 12, 2005
2,408
0
47
Clovis, CA
Oct 31, 2007
#2
  • Oct 31, 2007
  • #2
chris642 said:
I have been having some annoying problem with my 02 GT with a vortech runnin 6 PSI. the first thing i did when i got the car was put a vacuum/boost gauge on it, when i did it worked perfectly 21 HG and read the boost as it should. Then im a dumbass and think how cool it would be to have a blowoff valve so i buy one and throw it on not understanding the location of the MAF and how it wont work without a blowthrough setup. So anyway the car, of course, ran funny and wouldnt idle right and would stall on occasion. the vacuum also droped to 15 HG. So i then put the bypass valve back on to correct the problem and it did nothing but let the car run correctly and such, no stalling. The problem is the vacuum is still at 15 HG and now it says its not making booost! when i floor it the meter goes to 0 and may read like 1 PSI, idk its to hard for me to see when flooring it. I even went so far as to get a new bypass valve thinking maybe i messed up the other one taking it out or something, but it did nothing. I checked everything and its all tight, no leaks as far as i can see. i checked all the vacuum hoses and they look good and connected corectly. If there was a vacuum leak it wouldnt run right, correct? is my gauge messed up? i cant really tell if theres a power loss becasue when i got the car the tires were bald and all they would so is spin. WTF did i mess up? haha. any help would be great!
Click to expand...

If you have a vac leak, your idle would be high (like 1000+ rpm). If your boost/vac gauge isn't showing boost, I think your gauge is messed up some how. Check the nylon line for the gauge and make sure there are no kinks. Make sure the vac line (the one you have your gauge spliced into)is a nice tight fit. If you do have a vac leak, your car would run like sh1t, and the idle would be high. You can find vac leaks by spraying butane in different spots in the engine. If you find a leak, the butane will go into the leak source, and cause the engine to surge/increase in RPM. Hope this helps.

Tanner
 

BennyBlown2v

New Member
Dec 9, 2004
1,233
1
0
Carmel, INdiana
Oct 31, 2007
#3
  • Oct 31, 2007
  • #3
Check all the vacuum lines and have fun getting pissed off at the lil bastards lol. Also...did you put the bypass in the right direction? The stock bosch bypasses are directional.
 
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