Thank you for this cowboy. Fixed my neighbors es300, and fixed my ls400. Both had green corrosion on capacitors. Followed instructions, ordered parts. Took to a local guy named Li. He installed new capacitors. Both cars run great now. Es300 was losing fuel pressure, ls400 had delayed starting and would slowly die after coming off of freeway more than 50 miles. I got to my car early after learning from working on the es300. I changed my wording on my Google searches and finally found this thread after 3 months of troubleshooting the es300 on the weekends. Anyways I started made this account to confirm this worked for me.

 

Another example.
This ECU for a JDM 97 Toyota Crown uses also QAS (quaternary ammonium salt) capacitors and the problem was recently happened. As you see the 3rd photo, the lead wires are corroded and colored green. The ID marks are PR(M) and PF(M). The letter P means that the internal liquid contains the QAS. The Toyota Crown is only sold in Japan but the engine １JZ-GE is widely used and those may have the same problem

 

Might want to tell Cowboy to update the main post of the thread since the Crown isn't listed (though the 1JZ engine is).

I'd also be curious if the 1GZ-FE V12 in the Century would also be affected. Production started in 1997. It's not in our "troublesome engine" list, but I wonder if it had the same supplier. Problem is there are so few of the cars out there.

 

I know this post is old but I’ve been reading and I get more convinced every second that my Ls is having an ecu issue

first off it’s right in the age range and it’s been sitting for a long time the OBD2 scanner only works sometimes and it gives all kinds of codes every time we try to get it to work mostly the codes are misfires and sensors but I’ve replaced everything I’ve got it to turn over but it only goes into limp mode and only turns on when the driver side camshaft sensor is disconnected I’ve pulled the ECU and found some rust on the out side but no damage inside and nothing leaking could it still be worth replacing? The car has been having odd issues ever since I got it but I’m so confused that the ECU looks almost brand new on the inside

 

Human eyes are completely useless compared with an ESR meter to check electrolytic capacitors.

 

Would you please help me find the board locations to put new capacitors?
Also, you listed I needed a 15uF 35V - but you linked only to a 15uF 63V, is that ok?
Same with 100uF 10V - but linked to part thats a 100uF 35V?
How do I know if its low ESR, im not seeing it specified on the parts you recommend so I couldnt find it

Long thread, amazing!! Thank you!
94 LS400

 

Did this fix back 3 years ago, thanks to OP. I was having car shut-off issues. It basically killed the electronic throttle and I had to punch the gas to accelerate. I performed certain cap replacements and it fixed most of the issues. There were no cap leaks but I did notice that there were some malleable ones where it was easy to move a cap around. I still have hard shifting from 2nd to 1st when stopping. If I can go back, I would have switched out ALL caps.

 

https://www.clublexus.com/forums/ls-...ttle-body.html

It won't be perfect, but this makes an improvement.

 

oh nice! I wonder if this will work for the LS430 as well

 

I am not familiar with that particular engine, but it's the same family of engines so I imagine it has the same passages. And it would.

 

I did this fix for my 95 ls400 and it worked perfectly.
I've started on my friends 92 sc400 which is also showing all these symptoms and I've been looking around on this thread for information on what caps are needed but I cant find anything, can anybody help me out?
Thank you in advance, this will help out a ton!

 

There was a table posted somewhere of all the values required for each of the generations/model years.

My recommendation is to go with Rubycon ZLx series, or possibly RX30 as-per availability. Download and study the datasheets. You'll find that these have the lowest ESR (equivalent series resistance) of any, and the highest ripple-rating. They're also chemically-stable, long-term.

Do not attempt this job unless you solder professionally, or can find someone that does. This is military, or medical-grade work.

 

My 95-97 89661-50251 (9 caps) were replaced but it's still stumbling and no comm for diagnostics. Traces were damaged in many places. I plan to replace it with 89661-50341 or 89661-50303. Can anybody confirm it will work? Anybody got any experience? Will 303 / 341 need to reprogramming for car with 251 ECU?

Thank you.

 

Are you sure 89661-50251 is the correct number? 89661-50341 replaces 89661-50340

 

there you go....
as far as I can find, 89661-50253 replaces 89661-50250 or 50251. But they're all available as new $13xx++