1999 volvo s80 t6 wont go over 25mph!

kamel175 · Post by **kamel175** » 15 Oct 2009, 11:06

at first he car stuttered when first started up. after it warmed up it was fine. then it stuttered and wouldnt go ver 20-25mph while driving until after about 10 minutes of driving, then all of a sudden it wa fine and i got speed. now it doesnt go over like 25mph no matter what or how long its been running, even if i floor the gas. one mechanic says its oxygen sensors, another says maybe clogged fuel filters,lines or fuel injectors, still another says MAYBE the transmission. i bought it used and love it. can someone give me some advice?

Post by **vegasjetskier** » 15 Oct 2009, 12:35

You might be stuck in "limp home mode." Before you have any work done, take the car to a shop with a code reader and have the codes read.

jbrown122 · Post by **jbrown122** » 15 Oct 2009, 13:32

When you have the pedal to the floor, is the car responding? Does the car sound stuck in first gear, are the RPMs all the way up (i think the limit is 4k RPM).

I read about an S80 with the same problem, and it was an oxygen sensor.

I would change fuel filter, plugs, clean the throttle body and flush the trans (and put a new filter in).

Maybe you can narrow down some of your problems that way. If your a DIY person, it shouldn't cost that much to do.

fs · Post by fs » 15 Oct 2009, 14:45

I had similar problem on another car I had.....engine would rev fine in neutral/park but under load It just ran like crap...it turned out to be my cat converter(the insides fell apart or something) major exhaust restriction.......just a thought

lrblack12 · Post by **lrblack12** » 01 Aug 2010, 08:47

Is the accelerator responding or is it not revving past 2000 rpm? If it is not revving, check the accelerator/throttle fuse in under the hood fuse box, it is a 10 amp blade fuse. I am experiencing the same problem and the fuse continues to blow, once replaced runs fine until blows again. Not sure of underlying problem causing blown fuse still searching!