dicer, the fuel filter is ordered and on its way. But I don't have an easy way to check the fuel pressure

 

Although I really don't like the ECM clearing the codes every shutdown, I think Yamae is on the best track. The fuel pump resistor can cause some weird problems like that when they fail. If you can rev past 2,000 because of a clogged fuel filter I doubt you would be able to get past 10-20mph. It doesn't take much fuel to rev in neutral.

 

I would like to confirm that "bypass the fuel pump resistor" means removing the replay and bridging it with a wire. Thanks.

 

It can be simply done short-circuiting Fp and +B as is shown below if those terminals are wired.
https://www.clublexus.com/forums/ls-...ml#post8055172

 

I did the bypass, It seems a bit better, but still the rpm won't go above 1600 on the road. At parked, the idle can go much higher.

 

So then you didn't go look at the link Yamae left for you. All you did is replace the relay with a jumper wire. Its funny how if people just did what others here suggest lots of time and money could be saved.

 

Sorry, Maybe I miss something here. I thought what I did was bypass the replay. No? I tried to follow Yamae's link, But got confused I received the fuel filter I am trying to replace the fuel filter, now I could get the flare nut out. Did I strip the thread?

 

You need to use flare nuts wrenches on that flare nut. Flare nuts are soft metal and open end wrenches are nearly certain to round the corners.

 

All the talk was about the "fuel pump resistor". Not the relay, but if those cars are like gen1 then doing Yamaes link deal should by pass both the relay and the resistor.

 

Update, after replacing the fuel filter the car accelerates much better. Judging from the two holes at the two ends the filter has been clogged badly. Thanks everyone for the help.

 

Did this issue all of a sudden pop up or did it slowly start to occur?

 

This issue started within last month or so.

 

Glad to hear it helped. My filter was pretty dirty. The fuel coming out of the inlet side was a milky brown color full of sediment, almost looked like muck. I've been meaning to cut it open one of these days. Waiting for the fuel to evaporate and dry out.

 

That's what I've suspected, the fuel filter as I've stated previously. Most car owners do not pay attention to the fuel filter but it's a vital part in car's components, especially for cars being this old. Glad you've found the problem.