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Vacuum Probs???

  • Thread starter Thread starter PonyBoy84
  • Start date Start date Dec 30, 2003

PonyBoy84

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Aug 7, 2002
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Dec 30, 2003
#1
  • Dec 30, 2003
  • #1
I finally checked the vacuum on the 91 today. Coming off the tree, the vacuum seems low. I guess it should be in the 17-20 range, but it's more like 10-15 at idle. It is also not smooth and fluctuates a lot at idle.

When I give it gas, it drops then climbs back up to about 15 then shoots up to around 20 when I let off the gas (except for being low, I think this is normal. right?)

What would cause the low, sputtery vacuum at idle?
I think this may be the cause of the lack of power I've been having. The vacuum at the trans seems about the same as directly off of the tree so I think the trans vacuum hose is okay.
By the way, it does not idle smoothly either. Also, when I floor the gas pedal from a dead stop (to lock up the torque converter) the car just bogs down and crawls along.
 

351wcoupe

New Member
Feb 13, 2003
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Manhattan, Kansas
Jan 1, 2004
#2
  • Jan 1, 2004
  • #2
PonyBoy84 said:
I finally checked the vacuum on the 91 today. Coming off the tree, the vacuum seems low. I guess it should be in the 17-20 range, but it's more like 10-15 at idle. It is also not smooth and fluctuates a lot at idle.

When I give it gas, it drops then climbs back up to about 15 then shoots up to around 20 when I let off the gas (except for being low, I think this is normal. right?)

What would cause the low, sputtery vacuum at idle?
I think this may be the cause of the lack of power I've been having. The vacuum at the trans seems about the same as directly off of the tree so I think the trans vacuum hose is okay.
By the way, it does not idle smoothly either. Also, when I floor the gas pedal from a dead stop (to lock up the torque converter) the car just bogs down and crawls along.
Click to expand...

You can spray something around any suspected leaking area if there is a leak it will suck in the mist from the spray(WD-40) You could also you an auto stethoscope and listen for any leaks. If you don't find any leaks in the engine compartment check your heater controls. Amanda's car has a small leak in the vacuum control lines.
 
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