Club Lexus



Meet “Big Booty Betty” aka “the black pearl”, my new to me 2000 Lexus GS300 that was ran hard and put away wet long before I met her. Her paint isn’t pretty on the outside, but the interior is mint for a 22 year old car. She has some dents and damage, someone threw an egg at her and it stained the paint, and the wheels are all different colors, but She can only get better from here.



Starting a build thread for myself, so I can document the progress as I go. Feel free to follow along with me and provide and feedback or criticism.



I just picked up a 2000 GS300 with about 180,000 miles on it. When I bought the car I knew it had undiagnosed issues and wasn’t running right, but I got a good deal on the car and I didn’t feel like it would take much to get her going. The car would hesitate between 2k-3k rpms and sometimes it wouldn’t shift into the next gear unless I took my foot off the gas. The previous owner was upfront about the issues, and thought it may be a vacuum leak. The more I drove the car, the worse it got. Then the car pretty much stopped running all together. It would start, RPMs would drop below 1k, and then the engine would die.



First thing I did was replace the air intake with a used oem intake, used oem MAF, replaced the pcv valve, vacuum valve, and a few vacuum lines. I also replaced bank 2 sensor 2 O2 sensor. Nothing changed and the car sat in my driveway. Next thing I did was find a used fuel pump that I knew was working. When I took the existing fuel pump out I noticed the bottom half had broke in the past and a previous owner ZIPTIED IT BACK TOGETHER. WTF!? I was glad I found that because when I replaced it with a known working pump the car ran! Success!!



I thought all my problems with this car were resolved but I was wrong. I got a new CEL showing cylinder 2,4, and 6 were running lean. I also noticed that it I floored it the CEL would blink. The VSC light is on now also. Oh, did I mention that the airbag lights and the rear brake light indicator have been on also?



So this is where I’m at now. I still drive the car, and it runs well regardless of the dashboard lights lol. Still going to continue diagnosing these issues in an effort to get the car running perfect.



I have accumulated some parts for her that I’m going to fit as soon as I get some free time outside of work and family life. I have 2.5” universal exhaust tubing with mandrel bends, 2.5” straight through 1-to-2 muffler, and 2 18” slant cut exhaust tips. Going to cut and weld a home made cat-back exhaust. I’ve also been thinking about gutting the cats. The car came with a set of is250 18s, 2 of which were painted gray and the other 2 were stock silver. I’m going to sand them down and repaint them gloss black. I ordered some black center caps to complete the wheels. I also have some silver chrome vinyl wrap I’m going to cover the door handles with since a set of chrome door handles off an Aristo go for upwards of $35” used. Also have a TTE replica front lip. I have some other odds and ends for her as well that I’m probably forgetting.

 

It can be hard to come back from years of neglect. The car is misfiring when you floor it, you must mean 2,4, and 6 are misfiring, not running lean? Because you wouldn't be able to tell really if it is a leaning out issue. That would likely effect all cyls if it was a fuel issue or a whole bank if it was an upstream o2 issue IE: 1,2, and 3 or 4,5 and 6. Ignition issues are the most common culprit for misfires. Do you have any knowledge of when the last time the plugs and wires were replaced? It is very common for someone replacing them to damage the coil connectors and have misfires after due to poor connections. Just due to age and brittle plastic. Those are some things to check next. And be sure to brush out the throttle while you're at it then reset the computer with the battery disconnect method. Hope you can get it running good again.

 

Hey brother, thanks for your feedback. I really appreciate it. Yes! Misfiring, not running lean. My fault. The other thing I’ve noticed with the engine is at idle, like when I’m sitting at a red light, the RPMs drop to about 600 and the car shakes a little and then the computer seems to correct the RPMs. It then does it again, almost like it’s surging. I think k going to go ahead and replace the coils and plugs like you’re suggesting. Who knows when they were changed out last and based on the previous issue with the fuel pump, who knows if the correct parts or quality parts were used. Do you have any recommendations for coils and plugs that you use?
thanks again!

 

I'm a fan of NGK. I use their plugs wires and coils on my cars whenever I can. I have NGK iridium IX plugs and coils in my E60 530i, their plugs and wires in my 200sx, and plugs and coils in my GS, was using their wires too, but moved to some extra large wires for my bigger power build. You can get all of it form RockAuto. Very high quality, probably the best there is for OEM use.

 

I agree with these guys, Basic tune up and check your coil connecters. If its still acting up, send your ECU out to get tested. There are places that will test it for free if you pay your own shipping. If its bad, you buy you a replacement. Save yourself a whole bunch of time and expense by starting here.