bdazzler

Yeah, Eblick, do it yourself and save $300~$400. I just did. I was having an issue w/ my tranny not going into overdrive, error code 42 (speed sensor #1), and no cruise control. Changed the speed sensor first then tranny solenoids which did not solve the problem. Got a rebuilt ECU from Auto Computer Exchange (you can find them on eBay and they also have a website) for $225. It's just plug and play, biggest issue is getting access to it, depending on your model it should be either under your glove box or on the side of where passenger would kick it on the right (lower kick panel).

You could try to change the capacitors as per this thread if you are good w/ soldering https://www.clublexus.com/forums/ls400/656360-all-my-crazy-lexus-issues-solved-ecu-leaking-capacitor.html but I didn't wanna chance it w/ my limited experience with a soldering iron.

GL123

Here are the 10 capacitors for my 92 SC400 engine ECU
(# 89661-24240) California Emission model:

C806 - 15uf, 35V
C807 - 15uf, 35V
C350 - 10uf, 50V
C106 - 47uf, 63V **** See Note Below *****
C140 - 47uf, 63V
C110 - 10uf, 50V
C113 - 100uf, 10V
C108 - 10uf, 50V
C112 - 220uf, 16V
C507 - 100uf, 10V

NOTE: C106 is underneath the metal frame but can be accessed by bending slightly 2 adjacent components.

The correct replacement capacitors can be purchased from DigiKey as documented by LScomboyLS and Yamae elsewhere: https://www.clublexus.com/forums/sho...ferrerid=95518

I purchased a used ECU from eBay to practice on and successfully replace the capacitors on it and on my original ECU. I now have a spare.

Both ECU's are from the SF Bay area and did not show any leakage on their PC boards from any of the replaced capacitors. This may be due to the temperate climate in this area and simplified my refurbishing process.

The process of replacing the capacitors was a bit tedious since one had to be careful when removing the components not to ruin the plated through holes on the board. My recommendation is to send your ECU to a professional repair site. Be sure that they are familiar with the special capacitors required for this ECU repair. They have the specialized desoldering tools that simplifies the repair.

GISguy

^ Thanks sir.

unknown101

iTrader: (1)

I'm having a issue with my car...not sure if it's the ecu...my motor seems to lag a bit when I floor the gas padel...no engine light on..and no crazy idles. ...but I do hear a hiss sound...A shop told me I might have a vacuum leak..but I try to old break cleaner spray..and couldn't find it...so how do I no if it's the ecu...I open it up a couple months ago...and its still look like it's in good shape..

lexuscfour

My car exhibited similar symptoms. Would hesitate under light throttle from stops, generally under 40 mph. Ordered a repaired ECU from Darryl Geller in GA (stand up guy btw). He had the same as mine in stock already and sent it over, I'll send him back mine tomorrow, no core charge! Arrived this morning, installed and felt an immediate difference. Still got slight hesitation but nowhere near what I used to get. Ran some seafoam in the vacuum line and some in the tank and all I can say is NIGHT AND DAY. All that hesitation and whatever is GONE.

This all being said, don't worry about the ECU looking normal. I've seen some look brand new and still be bad. If it's never been repaired, it's the best place to start.

ems

iTrader: (1)

Im excited to get shorty SMC to re-cap mine! even if the caps aren't bad it will be a good time to change em all.

scblackout

iTrader: (2)

Shipped mine out to tanin yesterday, looking forward to see if it makes any difference. To bad I didn't know about the Geller guy as it would have been nice to do a core/swap instead of waiting with a week of downtime. About the only problem I have is when turning on ac, it comes on/off/on/off etc until I turn it off. Not sure if ecu will fix, but figure it can't hurt.

ems

iTrader: (1)

Tanin is quick though, I was surprised how fast they turn around

unknown101

iTrader: (1)

How much was the ecu?? And do u no if he got a 92 5speed in stock?

addisonblc

iTrader: (4)

Bummed for a great read.

ems

iTrader: (1)

I dont have any terrible symptoms but bought the cap set on stealbay, and hopefully it can go in this weekend. it was 17.99 and i know thats expensive for caps, but they are a matching set and all in one place... I said screw it. less runnin around hoping the sizes were right.

scblackout

iTrader: (2)

Got mine back from tanin, shipped only 2 days after they received it, so very fast turnaround. I should have expected it ,but the only thing I didn't like is that they add security warranty stickers to the ecu, so opening voids the warranty. So much for getting to see the shiny new caps...

Prior to sending the unit I was getting the p0171 (left bank to lean) and the 2 o2 sensor codes. Other than that the car was running great. Upon installing the ecu the car ran like it only had 2 active cylinders. I was getting a p0340? (crankshaft sensor code) and the car would barely run. I had run the car around the block once, didn't think I would make it back it was so bad. I came back about 20 mins later and started it again and this time it started normally and has continued to run fine since. It gave me quite a thrill thinking it was broken somehow, but in the end I think the ecu just had to learn how to work again.

Now the 2 o2 codes are gone and I am down to just the lean code. Other than that, I have noticed no difference anywhere. It is comforting to know that it will last a good long time now.

scblackout

iTrader: (2)

Took the car out again today and after about 3 miles on the freeway it began to drive like on 2 cylinders again. I made it the 3 miles to the next exit, shut the car off, restarted and it was fine. Drove about 30 miles with car running normal. Then when leaving car acted up again, back to 2 cylinder feel after multiple restarts, unplugging battery for 30 mins a few times, no luck. So decided to drive home anyway and after about 5 miles it began driving normally again.

Now I had never had this problem prior to ecu rebuild, and the car was not touched during time without ecu. Is it really possible that maybe somehow the ecu repair went wrong and it is the cause of these new problems?

It would just seem weird to have this brand new problem show up and also be totally unrelated right?

LEXOWINO

I own a 1995 SC300 and seems to have similar issues. The car groans from Neutral to First and seems hisitant and bucks at times.

Is their a list of capacitors available so I can purchase all of them and take the board to be serviced by a specialist.?

yauny

I had the same thing happen to me took ecu out on a friday noticed that 2 caps were leaking also this had already been repaired horrible I will say due to someone putting one of them in backwards. Will that do any damage to the ecu? I replaced caps properly and drove the car all day with no issues. Next morning turned it on and back to the old high rough idle and a surge idle bounces from 1300 to 1000 constantly in park and while driving feels like its not getting enough gas bucking sputtering like its missing. Haven't got the CEL check but am assuming its driver side cam sensor cuz that's where all the misses sound like they're coming from. Could the ecu be bad even tho I changed the 2 leaking caps. Also if the green coating is coming off the ecu board is that a bad thing? Thanks for any help