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Lose all acceleration after 3000 rpms

I have a 2004 saturn vue. It is a 5 speed standard with a 4 cylinder engine. Now that I have that posted here is my problem. I have normal acceleration up until I hit 3000 rpms. At that point my low engine power light comes on and I lose acceleration. To explain that better, if I take my foot off the gas pedal completely and then try accelerate again nothing happens. My engine stays on but I do not have any reaction when I push on the gas pedal. When I run the computer codes it says it could be my accelerator pedal sensor or my ecm. Any thoughts? I do not want to have to replace the ecm if I have to due to how expensive it is.

More than likely the problem is with the accelerator pedal position sensor.

https://www.rockauto.com/en/moreinfo.php?pk=1515678&cc=1428746&jsn=326

Even RockAuto sells them.

Tester

That would make my engine sound like it had little to no power? It also feels like it has no power. It struggles to accelerate after I hit 3k rpms. Sorry if I ask alot of questions. I don’t know much about cars.

Also if it was the ecm, wouldn’t it be having more problems then just the acceleration?

Ever change the timing chain and guides? Maybe ur motor is approaching the end? At least u don’t have the bad cvt trans.

It’s actually a rebuilt motor. It has only about 100k miles on the motor

It was rebuilt 100k miles ago? So it’s worn now

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The throttle position sensor (or accel pedal sensor, if that’s the case) isn’t part of the ecm, it’s a separate gadget that the ecm senses via a wire from it to the ecm .

Note that just b/c you have a code for that sensor, that doesn’t mean this problem is necessary caused for that reason. Those position sensors can usually be bench tested fairly easily, might be a good idea to ask a shop to do that.

fyi, at higher rpms and higher engine loads problems can show up that don’t show up at lower rpms and engine loads, for example

  • exhaust restriction
  • fuel delivery problem
  • valve/camshaft problems
  • ignition system problems

MAP/MAF problems can cause this symptom too. But they’d usually throw a code.