Henrys44

2001 Lexus IS300; Auto Transmission; 190k miles

What Ive done...

1) Full services at 100k and 200 k
2) Installed new Mass Air Flow sensor and air filter per recommendations online and reset ecu via battery discon and fuse disconnect

As the title states my engine is not throwing any codes and I have had the OBDII ran to ensure there were no codes. Yet when driving (or in park) The engine is limiting itself below 4000 rpm.

I can drive the car fine at normal speeds but discovered this issue when on a highway and attempting to accelerate to pass a vehicle. Of course I can have someone run a diagnostic but am hoping to gain some insight from lexus owners as Diagnostics are not fool proof in my experience.

Thanks in advance for any support or advice you can provide.

-Henry

NoMoreVTEC

Could be a number of things. Mainly fuel and air related. So let's start with basics.

Air filter good?

Spark plugs?

Vacuum leak?

No check engine light right? Sure the bulb isn't blown?

If all of that is find, it could be fuel pump related.

Test voltage to the fuel pump with a tester to make sure it's getting proper voltage signal. These cars have a voltage regulator that does what it's name entails.

If that is fine, check the fuel pressure sounds like fuel pump may be going bad.