I lost power cant go over 5 mile per hour and now my check engine and trac light come on and off and can not accelerate.i replaced the mass air flow sensor still no change

Yes rough Yes rough

in that case i would check your spark plugs, ign wires and ign coil. i'm guessing one of those is faulty and past a certain speed cannot keep up with the spark in that case i would check your spark plugs, ign wires and ign coil. i'm guessing one of those is faulty and past a certain speed cannot keep up with the spark

Would that stop it from accelerating Would that stop it from accelerating

While acceleration the rpms will drop to 0 While acceleration the rpms will drop to 0

yes it would. you could also have a clogged fuel filter, fuel pickup screen, or a bad/malfunctioning fuel pump. i would recommend going to autozone and getting a fuel pressure gauge and checking that out if replacing spark plugs and ign. wires does not work yes it would. you could also have a clogged fuel filter, fuel pickup screen, or a bad/malfunctioning fuel pump. i would recommend going to autozone and getting a fuel pressure gauge and checking that out if replacing spark plugs and ign. wires does not work

go out and get a fuel pressure gauge and check your pressure. if it's not around 35 psi then look at a malfunctioning fuel pump. that's probably the most likely problem go out and get a fuel pressure gauge and check your pressure. if it's not around 35 psi then look at a malfunctioning fuel pump. that's probably the most likely problem

I changed the fuel filter first then the mass air sensor I changed the fuel filter first then the mass air sensor

What about the throttle position sensor What about the throttle position sensor

i gauruntee then that it is your fuel pump. considering it's a lexus it may be pretty pricey like my land rovers fuel pump, but you may get lucky. also try putting some fuel injector cleaner in the fuel tank and running it for 10 minutes. if the idle starts to pick up as the cleaner runs through the system you have dirty injectors i gauruntee then that it is your fuel pump. considering it's a lexus it may be pretty pricey like my land rovers fuel pump, but you may get lucky. also try putting some fuel injector cleaner in the fuel tank and running it for 10 minutes. if the idle starts to pick up as the cleaner runs through the system you have dirty injectors

i really doubt it. if it was your throttle position sensor the car would idle fine or be too high and then start having worse problems as you drove it i really doubt it. if it was your throttle position sensor the car would idle fine or be too high and then start having worse problems as you drove it

May add I just went to emissions the before this started and I passed May add I just went to emissions the before this started and I passed

What about the cats What about the cats