OLDS bravada no power

i have a 1994 olsmobile bravada and when i floor it at a dead stop it doesnt move like it should, but when i am going 30 to 40 and floor it it has power.....whats wrong with it.

What have you checked so far?

We replaced the fuel pump and the main computer. we are being told the #5 cylinder is mis-firing and because it is a "spider" we will have to replace the whole thing.

Before you spend any more money on the vehicle, I would suggest checking the fuel pressure and leakdown rate. The ECM (Electronic Control Module) is a very substantial piece and rarely needs replacement. Most of the time, it is replaced due to a technician not following the diagnostic flow charts correctly.

How do we check the fuel pressure and leakdown rate?

There is a service port on the fuel pressure line very close to the distributor. Key on, engine off, pump running, pressure must be 60psi to 66psi. Pressure must remain above 55psi for 3 to 5 minutes after the pump shuts off. Check your AF inbox.

Here's the service port,

http://i131.photobucket.com/albums/p288/Clunk_/Image033.jpg


Fuel pressure test kits are available at most auro parts stores and Harbor Freight.