im new to this forum and i just bought an is300 about a month ago.
i need help figuring out what this problem is. sometimes when i just start up the car on a cold engine and take off, the car will bog a little. then on a normal basis of driving, ill smash the pedal to pass someone and exactly at 4000 rpm it bogs out and pretty much slows the car down. after 4000, like 4200 or so, its fine. idk what the problem is and if anyone is familiar with this problem id be happy if you could let me know. thanks.

 

does anyone have an idea of what it is?

 

I am not a mechanic but if you have a high mileage car, you may need new plugs & wires. I had a similar problem with my previous car and that might fix the problem but it wouldn't hurt.

 

yeah it has very high milage. 186k. but thanks, ill try to change it and see what happens.

 

You would most definitely need new plugs if you haven't changed them before. The previous owner may not have changed them either because the IS300 is an inline V6 and the plugs are not easy to get at. Good luck let me know what happens after new plugs and wires.

 

yeah i kinda figured. haha. alright ill let you know how it goes.

 

clean your MAF sensor, mine did the same, cleaned it and it was fine

 

Mine does the exact samething...01 with 130k..

 

Just performed a timing belt service on mine. Also changed the VVTI sprocket(which I believe took care of the bogging). The car now performs like it should with no bogging. Before I had cleaned the MAF and replaced the VVTI silenoid(which did not cure it). I also noticed that the sproket had moved some compared to the new one.

Hope this helps a little.

 

if i got an 01 auto IS do i get VVTI?

 

look at the motor.. does it say vvti?

should be a big lump sticking out the front right side of the head,,, instead of flat across.

 

bogging is going to be a timing issue. this can be troubleshot by doing steps first before just jumping to the belt.

clean the maf, use non-film electronics parts cleaner, autozone has good stuff for cheap, its in a red can with a small black top

unplug the battery, unplug the maf and remove it.
spray the sensor that is visible, also, there is another up inside the slotted area, spray in there.
let it dry for 15-20 minutes.
reinstall, plug in,
reset the ecu...... cant remember if this is doen by steppin on the brake a bunch of times or the gas,, but it is BEFORE the battery is reconnected.,
reconnect the battery
start, see if that fixed it.

if not:
check the plugs- could be one is fouled. make sure your using good gas and the CORRECT OCTANE must be 91. try putting a bottle of HEET in with the next tank,, use the yellow bottle.... nearly pure methyl alcohol

if that all doesnt work, try checking your igniter and then look into doing the belt.

check the timing as well BEFORE you do all these steps

 

will try that out for sure thx for the advice buddy!!

 

while you're doing all this take the intake pipe off as well and clean the throttle body too. Just get a can of carb cleaner & red shop rag.

spray it real good,,, on the butterfly, manually open the butterfly with the throttle pulley and clean it all out.

 

I removed my tb to clean it and it made a big difference