1999 GMC Suburban No power

DSVOLDEN

MEMBER
1999 GMC SUBURBAN
V8
4WD
AUTOMATIC
176,000 MILES

My 99 GMC suburban has no power. If you push the gas pedal down it will not go. If you let up, it will accelerate slowly. The codes that came up are P0131 and P1870. Where would I start?

Monday, March 16th, 2009 AT 6:11 PM

5 Replies

RASMATAZ

MECHANIC
75,992 POSTS

Sounds like a transmission slipping problem. Check level and condition of the fluid if it continues get it pressure tested.

Also check and test the throttle position sensor

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Monday, March 16th, 2009 AT 7:04 PM

DSVOLDEN

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3 POSTS

I forgot to mention that when it's cold outside, it runs good. Do you think it could be the O2 sensor?

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Tuesday, March 17th, 2009 AT 6:53 AM

RASMATAZ

MECHANIC
75,992 POSTS

Could be it came up with P0131

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Tuesday, March 17th, 2009 AT 2:01 PM

DSVOLDEN

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Ok, I know it's been awhile. I changed the transmission and it ran ok for a month or so. Now, it is losing power again. Exactly the same way. New throttle position sensor, MAf sensor. Any ideas?

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Saturday, June 12th, 2010 AT 7:27 AM

SWSIMONTON

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1 POST

It was transmission fault it has nothing do to engine. I had same problem it was shift solienod problem when I put in 1 gear got power when I shift to 2 at 30 mph took long time to chaange in 2 gear so I has change all solienod inside pan of transmissin finilly got shift correct at start. Got horsepower back normal. Pain in ass !