Mechanics

LOST POWER

2005 Isuzu Ascender • 6 cylinder 2WD Automatic •

2005 isuzu ascender. On long trips on interstate, car would lose some power(still runs, but little power), would be fine after a couple of minutes. Now is continual problem. Changed air filter but not much help. What should I check next?
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Papadc
July 12, 2011.




I would check for codes and restricted exhaust to start with.


Saturntech9
Jul 12, 2011.
Verify the fuel pressure and comeback with the readings-we start here
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Rasmataz
Jul 12, 2011.
How much of a chance could it be the catalytic converter?


Tiny
Papadc
Jul 12, 2011.
I dont know odds thats why I said do a back pressure test to check for possible cat issues have it scanned for codes and checking the fuel pressure like rasmatz said wouldnt be a bad idea.


Saturntech9
Jul 12, 2011.
Had it scanned last week. Only problem shown was some to do with the engine being 21% but should be around 5 or 6 %(or vice-versa). Sound familiar?


Tiny
Papadc
Jul 12, 2011.
Old code was something to with something "below threshhold". Had it erased & it hasn't come up again


Tiny
Papadc
Jul 12, 2011.
That really doesnt ring a bell 21 percent of what?Throttle postion?Dont really know need more details about that one. How checking the fuel pressure and back pressure?


Saturntech9
Jul 12, 2011.
P0420

Check the Catalytic Converter if its clogged-up by doing what Sat9 suggested on backpressure test of the exhaust system-


Rasmataz
Jul 12, 2011.
Would have been helpfull to have known the exact code number it was.


Saturntech9
Jul 12, 2011.
Not sure. Idles fine, doesn't skip. But when I press gas pedal a little hard, it doesn't want to go. If I ease into the gas it will evenually get to normal speed


Tiny
Papadc
Jul 12, 2011.

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