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Apparent lack of power while accelerating

2K views 9 replies 6 participants last post by  myfirst Astro 
#1 ·
Okay, i am not certain of the component that is causing this issue, so I posted in the general section. Driving back from a camping trip yesterday it appeared that my van was not accelerating very well. I would have to push the pedal down more to achieve normal acceleration. Once the vehicle was up to highway/freeway speeds it would hold speed just fine, with normal pedal operation. I checked the trans fluid, it is clean and at proper level. There are no leaks of fluid anywhere. Engine temp is normal, other gauges are normal. The vehicle rolls just fine, so I would assume that rules out a locked up brake cylinder. The vehicle idles fine, and it doesn't miss or anything. Sometimes under acceleration it does seem to have occasional surges without any change in the gas pedal position. Surges are not drastic by any means, but you can tell the engine picks up a notch or two. The check engine light is not on, so it hasn't thrown a trouble code.

So just trying to get an idea of where to start troubleshooting. I was thinking to test fuel pressure first. The fuel filter was replaced about 10K miles ago, but the fuel pump is the original stock pump. Or possible a plugged cat? Bad o2 sensor?

Any suggestions are appreciated, and let me know if you need more information.

Thanks.
 
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#4 ·
Definitely check that fuel pressureand TPS as Leeann suggested, but something as simple as a 20 or 30 degree hotter day, or being in the mountains, or a batch of gas with more than the usual amount of ethanol ( or just plain crappy gas) can make a vehicle feel like it's got a 10 foot anchor dragging too. :2:
 
#6 ·
I think there is something in the book about rigging up the TPS and an ohm meter, or you can check the output volts from the sensor with the throttle closed and slowly open it, the voltage should either rise or fall (can't remember which) :confused:

EDIT: Should finish what I start, the readings should be smooth and not jumpy...if they are jump or erratic, suspect the sensor.
 
#7 ·
Well, I started the van up and the problem was not there. It has been over a week and I have not be able to replicate the problem. Perhaps I was just out of it that day or something, I don't know. I guess I'll wait and see if it occurs again.
 
#10 ·
Hi there,

Mine did the exact same thing today and also on the way back from a camping trip :confused:

But I do know that my 1992 RWD has a leak from the transmission, I have to keep it topped up.

When going up hills/overtaking it wont kick down, well sometimes it does but just makes a lot of noise and seems to get bogged down.

It did it today and also seems to have a misfire.

Any thoughts as where to start

Plugs ?

Regards

Andrew :chevy: :chevy: :chevy:
 
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