sailemt

Hey crowd...Over the last few months I was having a problem with my 2002 SC430 with 130,000 miles having random hiccups and engine hitches during acceleration and even at random times while on the highway or around town. My average 10 minute trip around town would have at least 10 hiccups, all random and during no specific style of driving. No one wants a stuttering engine!

After reading some of the threads here there were several options...
1. Do a system reset by using only the key turned on and pressing on the gas pedal for thirty seconds. While optimistic, this didn't solve the problem...
2. Many threads suggested that it may be my TPS (throttle position sensor) so I started shopping around for a sensor to install myself. They run for about $75 online and are a pretty easy install..but I wanted an official opinion so I went into my local lexus dealership to ask them if this was the best course of action...

The solution: Apparently, the 430 engine is a notorious carbon producing engine so, as my local lexus mechanic explained, this carbon can build up in the throttle body, affecting how the mass air flow sensor (MAFS) is read. My mechanic recommended having a FUEL INJECTION SERVICE. This service cleans the fuel deposits in fuel injectors and carbon build-up in cylinder heads and in the throttle body plating. It cost me 1 hour worth of labor and $50 for the cleaner for a grand total of $189.00 IT WORKED! I have been driving the car for a month now and I have not had a single hiccup, hitch or hesitation. This was money very well spent! My lexus mechanic recommended having this system cleaning every 30,000 miles so this is a small price to pay for a healthy, happy car.

Hope this helps and happy driving!

Scarletti

Useful to know, thanks for the post (and your 1st post! too). o/

bb430

iTrader: (1)

Maybe once a while we need to perform an "Italian Tuneup". Full throttle pedal to the metal run for couple of gears couple of times a week. :-)
Where I live, there is an overpass to the other side of the freeway with a little up hill run, I have been doing this everytime I catch a red light before it.

husker741

But officer, I was just getting the carbon build up out of my engine...

Rollaboy

iTrader: (1)

Quote:
Originally Posted by bb430
Maybe once a while we need to perform an "Italian Tuneup". Full throttle pedal to the metal run for couple of gears couple of times a week. :-)
Where I live, there is an overpass to the other side of the freeway with a little up hill run, I have been doing this everytime I catch a red light before it.

Quote:
Originally Posted by husker741
But officer, I was just getting the carbon build up out of my engine...

jzwu

Redlining the engine from time to time is a good way to burn off carbon buildup. It is true for all cars.

I do it on my BMW more often than on my SC430. Guess the SC430 invokes a relaxed and serene ride, so not many drivers do it. The best way to redline it is to use c-gate shifting on pre 2006 cars. It also wakes up the beast inside. LOL

diagtime

but officer, checking the oil on the LF-A requires several full throttle runs. (true by the way)

Yes......run the motor hard. it was built for that. it was not built for pansy drivers on short trips.

SC400-V8

iTrader: (1)

Same problem here, 2002 SC430, the last few months I've noticed the acceleration sucks, the idle isn't smooth and a terrible smell when the vehicle idles....

I used a stopwatch to time 0-60 and it delivered an abysmal 9.3 seconds..

i dumped two techrons in the fuel tank and ran it like 50 miles, the acceleration and idle smoothed out ALOT, so I did another run and it came back 8.9 seconds, quite an improvement, but still not close to what it should be.

its in getting a full fuel system cleaning at the Mobil shop near me. It's $109, hopefully it restores it.

Caflashbob

A set of sparkplugs would be my first thought

Bgw70

i decided to go this route, I cleaned three fuel systems with the device, very easy to connect.
Here is the thread on this subject...
https://www.clublexus.com/forums/sc4...-on-sc430.html

and the price is still $125 shipped...
https://www.jbtoolsales.com/otc-tool...aner-canister/

ShawnOk

iTrader: (1)

Search above in the search bar for the "Trans Pressure Mod." It might be something of interest to you. Oh and I'd recommend cleaning out the throttle body and maybe some Seafoam through the PCV valve. Can't forget about the ECU reset/battery reset too. Those things made a huge difference in my SC430.