Pontiac Repair: Metro acceleration problem, pontiac man, throttle linkage

Question
QUESTION: Hello Todd, I know you are a Pontiac man but the Chevy guys are all on vacation so hopefully you can help me out. I own a 99' Metro with the 1.3L engine and 55,000 miles on it. When accelerating from a stop the car will barely move for about five seconds even with the accelerator on the floor. This occurs with the a/c on or off but it is really pronounced with the a/c on of course. After the five seconds it will pick up speed like normal and run fine until I stop again. I have checked the plugs, plug wires, air filter, fuel pressure, throttle linkage for bindage, injector resistance and all of that is fine. There are no codes in the computer either. Any ideas?

Thanks,
Rennie

ANSWER: Hi There:

Well I have never even worked on one of these cars but if you have an extreme lack of power "dead spot" it would look at a few things restricted exhaust system. take the front exhaust pipe off the engine's naifold and drive it to see what happens. You could have a fuel pump issue where it has pressure but not enough volume to run the engine undewr a heavy load. lastly would be an engine sensor that is giving a skewed reading to the computer. Not one that is catually gone bad enoughto cause a service engine light to come on but enough to disturb the fule delivery to the engine.


---------- FOLLOW-UP ----------

QUESTION: Todd, thanks for the helpful and timely response. I really appreciate it. I do have a couple of questions when checking the fuel pressure with the ignition key on engine off. Is it normal to have to prime the pump twice when the engine is cold before the pressure is within specification? Also should the pressure fall about 10-15 psi immediately after priming the pump or should it hold steady?

Thanks again,
Rennie

Answer
the pressure dropping 10-15 PSI is a bit excessive I would think tht maybe 5-10 MAx would be the norm..Having to prime it 2 times is not good either unless the extra prime was to get the gauge to work.. leave the guage on the car for about an hour with the key off the pressure should drop off all that much I don't know how much is normal on that car.. . If possable drive the car with the gauge on in if it has a log hose and see if the pressure dropps off while driving it when it has that hesitation.. If so I'd suspect that the pump has an issue and it can't keep of with the demand the engine needs.