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no power above about 3k rpm...any ideas?

  
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no power above about 3k rpm...any ideas?

 
91zeee 91zeee
New User | Posts: 1 | Joined: 04/11
Posted: 04/03/11
06:55 AM

I just found this forum. Good to see there is a forum dedicated to TPI. I hate to have to ask for help on my first post...but... here goes....

Stock 305 TPI. If I floor it, it pulls pretty strong to about 3000 rpm. Then it starts to get weak. By 4000 rpm it has pretty much stopped pulling, the rpms climb real slow, it sits there at about 4500 for a second or two and then reluctantly will shift. Then the rpms drop to 2000 or so, it pulls strong again and then at about 3000 rpm the whole process starts all over.

I thought I had a tranny problem (governor or something) that was keeping it from shifting; however, something is clearly happening to hold this motor back above about 3k rpm or so.

I have already replaced all of the injectors, fuel filter, cap, rotor, plugs, and wires.  The fuel pump was replaced before I got the car about 3 years ago.  

TGO_SUX TGO_SUX
New User | Posts: 10 | Joined: 02/11
Posted: 04/04/11
08:38 PM

Normal cruise, does it shift properly into all gears?

Look at your converter when its cold. Does it look dark on the engine side? Look at it after driving. Is it red hot? May be plugged. And red hot manifolds? If you have a back pressure gauge that would help. But darkened or glowing red is a good clue.

In park, does the car freely rev and hold without problems?
just because a pump was replaced does not mean its still good. What was it replaced with? Crud off *** e bay?

And if there is a problem shifting, while you're under the hood, look at the TV cable. Should be able to open the throttle full and the cable should be tight.  

pepsi1 pepsi1
User | Posts: 111 | Joined: 09/11
Posted: 05/26/12
12:06 PM

I just need to add one thing. A fuel pump especially an eletric pump being replaced 3 years ago is not a new pump.

FYI: You don't know if the pump was ever run out of gas and if so how many times. 1.Electric fuel pumps,are cooled and lubricated by the fuel in the tank.
They also have a prefilter or a sock that if it wasn't replaced could be a problem. The way it lays over on you could indicate that it running out of gas at higher RPM.
2.You could have a mechanical problem internally in the engine. You could be experiencing valve float. or the cam could be wearing out.

It could be something as simple as a fuel pump that can't keep up...I've put a fuel pump in and in less then a year replace it again..

Whats the engine in?
How many miles on it?
What trans?
What rear gear do you have.
Whatever info you can give us will help