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Car looses power when accelerating!

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Old 12-07-2007, 08:44 AM
  #11  
Daze
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Default RE: Car looses power when accelerating!

did you check the accelerator pump and vacuum advance?
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Old 12-07-2007, 02:18 PM
  #12  
jlg2002
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Default RE: Car looses power when accelerating!

Bogalu,
You're missing the point. Just cause they're new don't mean they're good. I taken several "new" parts off (that were bad) the day after they've been changed when I was turning wrenches for a living. Start with a basic ( suggested herein by several floks) troubleshooting plan and discount the good findings--that doesn't mean you have to go out and buy things. You'll very likely never go right to the "bad" thing on the first attempt.
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Old 12-08-2007, 07:23 AM
  #13  
Bogalu
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Default RE: Car looses power when accelerating!

Well the carb went bad once before. This is an even newer carb. I think there may be a intake manifold leak. Would that explain the problems I am having. The old carb had a accelerator pump go bad. It would barely even start so I know that that isn't the problem. The carb is tuned up. The float bowls are good. So I am leaning towards the intake manifold. Someone told me that spraying carb cleaner around the intake manifold can check for a leak if the car accelerates when you spray it. Does that work?
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Old 12-08-2007, 08:05 AM
  #14  
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Default RE: Car looses power when accelerating!

ORIGINAL: jlg2002

Bogalu,
You're missing the point. Just cause they're new don't mean they're good. I taken several "new" parts off (that were bad) the day after they've been changed when I was turning wrenches for a living. Start with a basic ( suggested herein by several floks) troubleshooting plan and discount the good findings--that doesn't mean you have to go out and buy things. You'll very likely never go right to the "bad" thing on the first attempt.
+1

My step dads old truck had a problem holding charge once. I checked everything, alt, battery and they were all fine. No frayed wires, corroded terminals. He replaced the alt, twice, with no change. That's when I looked at thetruck.I looked at him and said, it's your voltage regulator. We went out and bought one. I installed it, jumped the truck and it did the same thing. I said, I guess I was wrong and re-installed the old one.He brought it to the garage and we got a call a few hours later. Guess what part was bad. The regulator. I was right and the part we had gotten as a "Brand new" part, was broken. Unfortunately, Advance auto is notorious for that.
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Old 12-08-2007, 09:59 AM
  #15  
Daze
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Default RE: Car looses power when accelerating!

a manifold leak could be the problem, and yes carb cleaner is a good trick to check. It may not get faster though, some times it just smoothes out. Did you check the vacuum advance?
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Old 12-08-2007, 10:12 AM
  #16  
JMD
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Default RE: Car looses power when accelerating!

The first thing I thought of when reading your post was that the car was running out of gas upon acceleration, a fuel delivery issue of some description.

But, you have replaced everything, while you may have swapped in a bad part, or you may need to adjust your carb, I am more inclined to believe you are suffering from an ignition issue.

First, make sure that the filter has not become plugged up, and then it is my opinion that you should move on to the ignition. Start with your coil. A weak coil can often diminish he spark to a point where the car will run ok when idling or tooling around, bet has difficultydoing its jobwhen the engine is under higher stress. This happens because the spark has to be stronger to jump the spark plug gap when the engine is working harder. Increased cylinder pressures increase resistance across the plug gap, and higher RPM reduces dwell saturation in the coil, also reducing the spark power.

A marginal coil will show its weakness under demanding situations.IMO start with your coil. Especially if you have an Accel brand coil....

I have seen many a parts changed and a lot of troubleshooting done,all for nothing when acoil was all that was needed..... buy a chaep one to troubleshoot with....
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Old 12-08-2007, 10:15 AM
  #17  
mustangmatt63
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Default RE: Car looses power when accelerating!

I would check for Vacuum leaks,intake leak,fuel pump and the timing and vacuum advance!! Also make sure all the NEW parts you said you put on are actually GOOD.New doesn't necessarily mean god as I have found out personally many times!!
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Old 12-08-2007, 01:24 PM
  #18  
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Default RE: Car looses power when accelerating!

Another great tool for checking vacuum leaks is a hand held propane torch (not the super little ones... You want the ones with some volume behind them)

just start the engine up and open the valve on the torch....(Dont light it) then fog the unburned gas around the suspected problem children (carb/intake or whatever) If at any point the engine changes tune (smooths out revs etc) you know its pulling air through that spot.

If you cant get propane then carb cleaner or starter fluid will work but its a bit more toxic to breath and makes a bit more mess and may dissolve paint.

happy hunting

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Old 12-08-2007, 02:20 PM
  #19  
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Default RE: Car looses power when accelerating!

mine had trouble accelerating and found out i had no bottom end torque left and like 2 lbs of oil pressure. so i pulled my motor. and the whole thing inside everywhere looked like gunk hell. someone hadnt changed the oil in like, forever. whoever had it before me.
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Old 12-09-2007, 02:09 PM
  #20  
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Default RE: Car looses power when accelerating!

ORIGINAL: true66gt

mine had trouble accelerating and found out i had no bottom end torque left and like 2 lbs of oil pressure. so i pulled my motor. and the whole thing inside everywhere looked like gunk hell. someone hadnt changed the oil in like, forever. whoever had it before me.
"I change my oil, why worry about gunk?"


"Yeaahh, right!"


". . . . and some extra napkins."





5 points to the first person who can name the Mighty Ducks star sitting in the car.

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