Alright, I am going to preface this by saying that I am still a relatively new ISF owner. Car has 125k.

I have tried a few 0-60 runs and I am getting nothing better than about 5.5 seconds. Traction control/VSC off, sport mode on, pedal straight to the floor, manual mode shifting at beep, no brake preload, about 90 degrees out and pretty humid.

Only mods are the aFe dry filter and muffler delete. 80%+ tread on Michelin PS4s at factory pressure. I just ran through a tank of Royal Purple fuel system cleaner less than 100 miles ago.

Gas mileage seems good, car runs smooth, but does feel like it is running at about 75% power when I punch it. It really felt like I was back driving my IS350.

My first find here on the forum was that the Mass Air Flow (MAF) sensor could be dirty and and causing the sluggishness. So I went to pull it off and while I was looking at my can of CRC MAF cleaner, it specifically said "Do not use on Lexus vehicles" because of a "Karman-vortex" sensor.

What kind of cleaner should I use to get this cleaned up?

My second find was to reset the ECU. I pulled both the 10a and 25a fuse from the box on the drivers side for a minute or two and popped them back in. Have not tested this yet.

I do know that it is definitely time to change the spark plugs, but those are in transit over the holiday weekend and I am just trying to tackle anything else I could do to remedy any other contributing factors while I wait for them and keep my fingers crossed that they are the culprit. They were changed at 60k by the original owner at a Lexus dealer.

I read one or two posts were people felt like the plugs made the car feel more responsive, but can anyone attest to a a solid one second gain in their 0-60 time??

*I first noticed this when I found myself getting beat by half of a car by a Pontiac GTP at a couple of red lights...

 

 

So, I went out and did a few things to try and remedy this issue over the long holiday weekend.

1. Seafoam - as recommended by a post made on another thread by RRRacing, I went ahead and used a vacuum line to suck up a can of Seafoam. It didn't create the massive clouds of smoke that you see online, but it did create some. I also had a lot of smoke coming up from the header area, which I think confirms my suspicion that they are cracked and need to be replaced with PPE headers soon.

2. Mass Air Flow sensor cleaning - I used some Isopropyl Alcohol (My can of CRC said NOT to use on any Lexus vehicle) and a fine mist spray bottle to clean off the mass air flow sensor. It definitely removed a little build up.

3. Spark Plugs - Since I am at 125,000 miles, I know it was time to do the plugs. They were done around 60K according to Lexus records, but they look pretty fouled up, IMO. Any thoughts on causes as to why the plugs looked so bad?

4. Compression test - I also checked the compression on all 8 cylinders while I was changing the spark plugs. (Pulled the Fuel Pump 25a fuse)
Drivers Front - 178
Driver Second - 182
Driver Third - 180
Driver Rear - 178
Passenger Front - 179
Passenger Second - 176
Passenger Third - 183
Passenger Rear - 183

5. ECU/TCU Reset by pulling the two fuses for one minute.

All in all, it took me about 5 hours to do all of this and I must say that the car is performing VASTLY better than it did before. Normal mode feels like Sport mode used to, and Sport mode feels like Race mode now. The car pulls MUCH better than I expected it would from a roll. However, from a stop, I still couldn't get any better than 0-60 in 5.0 seconds, any way I tried. It feels like the car has some spots of hesitation in the early RPM areas until it is up to about 30 mph. Almost like the tires are spinning, but I don't hear any noise or feel traction break loose.

Is there any chance that checking and resetting the transmission fluid level will help out with this a little bit? This is my next task to perform either way as I am pretty confident that mine is probably a little low.

 

Have you checked the kclv and knock feedback values? Obdfusion and an obd2 wireless reader is what you need. Get the values up and try again.

 

 

Those are definitely on the to-do list. Right now I am focusing on getting all of the maintenance in order. I can't wait for headers and H & S exhaust + RRRacing Tune!