RA40

iTrader: (6)

DETONATION, contact Digikey and see if they can give you a cross reference for those.

Caseyjones

I just ordered based on the information on post #1 for my 96 LS,

1995-97*LS400 needs 6 caps as follows:
Qty. 2 of 10uF – 50v
Qty. 1 of 47uF – 63v
Qty. 2 of 100uF – 10v
Qty. 1 of 220uF - 16v

When I started chasing the links below I ended up with caps of the same uF but a couple were considerably higher voltages, which is just fine if I correctly understand what I read. I hope this is right.

I'm glad I saw the bits about heat, I have a 40 watt pencil iron and one of those de-soldering vacuum pencils. I hope this is right also

I ended up ordering these per the same post links, hoping these are proper, ordered twice as many as I need as I strongly suspect my wife is going to want her own LS pretty soon.

Qty. 2 of 10uF – 50v get in*10uF*is the 50V Chemi-con KZE*EKZE500ELL100ME07D
Qty. 1 of 47uF – 63v *is the 63V Panasonic FR*EEU-FR1J470B
Qty. 2 of 100uF – 10v 100uF*- the 35V Rubycon ZLH*35ZLH100MEFC6.3X11
Qty. 1 of 220uF - 16v new 50V Nichicon HW is my new favorite!*UHW1H221MPD

I dont have any real reason to think that my ecu is defective yet. My only symptoms are
1. Idle slightly rough until warm, I mean very slightly.
2. Low end torque and power a bit less than I would suspect for such a great engine.
3. MPG is less than I would expect at 350mi/tank

I want to make sure this car is ready for another 170k mi so along with the ECU caps I'll also be doing plugs/wires/dist caps/coolant temp sender for ecu/transmission mount/strut rod bushings. Good to go! I will report back any changes I get from installing the caps as I will be doing that first and alone.

I also want to ad that Digi-key has shown outstanding customer service and top drawer professionality. Also 2x the caps I need were $9 shipped. Not seeing a downside here.

lexmoose

Higher voltage is fine, caps are physically larger, but still fit nicely in the ECU.

I've done the procedure with my Weller WESD51 (50w) and I had a hard time with the negative lead (dissipate the heat too quickly) . I finally manage to get them out, I did a few 5-6 seconds shot alternating with the 6 caps to let them cool down a bit between each try.

I suggest also you leave a small gap between the board and cap to inspect the solder on both side of the PCB

DETONATION

I took your advise and contacted Digi.
Can I pry you brains? Should these work?

493-1737-ND PW series 100uF 10V Nichicon 2mm lead spacing
http://www.digikey.com/product-searc...ds=493-1737-ND

493-1934-ND PW series 47uF 63V Nichicon 3.5mm lead spacing
http://www.digikey.com/product-searc...=493-1934-ND++

493-1783-ND PW series 220uF 16V Nichicon 3.5mm lead spacing
http://www.digikey.com/product-searc...ds=493-1783-ND

493-1890-ND PW series 10uF 50V Nichicon 2mm lead spacing
http://www.digikey.com/product-searc...ds=493-1890-ND

P14495-ND GA series 15uF 35V Panasonic 2.5mm lead spacing
http://www.digikey.com/product-searc...ds=P14495-ND++

DETONATION

If this is the case and they would work than for an aristo 2JZGTE ECU. These are the 9 caps I would need for the job.

3x H9141 47UF 63V Digi part #: 493-1394-ND
2x H9149 10UF 50V Digi part #: 493-1890-ND
2x H9134 100UF 10V Digi part #: 493-1737-ND
1x H9143 220UF 16V Digi part #: 493-1783-ND
1x H9149 15UF 35V Digi part#: P14495-ND

Yamae

I don't find any ESR data there.
You can't expect good results without selecting low ESR electrolytic capacitors.

DETONATION

Digi said that they don't have that information, and to contact Nichicon and Panasonic. How can I ask them if I don't have anything but Digis part numbers?

* UPDATE , I emailed both companies yesterday.

mjkwee

Update on my fixes to my 1992 LS400 with adapted equipment for my disability.

First the problem that got me started in this thread is my car stalls during very hot sunny days. This happened twice with consistency. Driving along the Highway on a hot day the car begins to stall after 20+ miles then dies. Waiting for 15 minutes the car will restart but will stutter and die again. However, letting it rest overnight, the car runs fine without problems but the car has overtime have not run as peppy as it once used to run. I took my car to my mechanic twice and they could not find the stall problem. So I suspected my ECU may be the problem.

I decided to invest on a used ECU from eBay and bought my caps from Digikey, pictures in previous page posting #896. Being disabled I needed my car to go to rehab. I had my neighbor, an Arcade repair guy, replace my caps. In the process I decided to also replace my 20+ year old ECT (Engine Coolant Temperature) sensor today as a matter of maintenance and it is an input to the ECU handling. Here is the link to ECT thread https://www.clublexus.com/forums/ls4...ange-pics.html
I started the car after the ECT replacement and I experience a tremendous boost in the engine roar and it was noticeable when I drove it too. I can feel the increased power. Picture of the old ECT BELOW Toyota P/N 89422-20010 is $42 on eBay from Seller Toyota-warehouse. The part arrived in 3-days.

My next step is to swap the ECU with the new Capacitors next week. My 1992 LS400 has 10 of the capacitors. I'll see if there is any noticeable improvement to the performance and function with the ECU swap. I disabled my A/C a couple of years ago because of compressor problem. After the second time only two years apart it was costing me money. I learned in this thread, one of the symptom with the ECU capacitor problem is the A/C. I would love to get cool air again.

I will update my journey to fixing All My Lexus problem. On my list to do is cleaning my MAF (another input to the ECU) and I also have my oil lamp come on intermittently too. I purchased Toyota Oil filters in case they use replacement oil filters for my Lexus.

t2d2

iTrader: (8)

Wow, this thread is awesome! I had previously seen the frequent recommendations to check the ECU capacitors for leakage, but never anything nearly this specific for fixing them or even identifying the root of the problem.

My '94 SC400 has some of the symptoms from the first post but no visible capacitor leakage. This thread has convinced me to pull the ECU out again and record the μF rating on each of the 9 (?) caps. I'll report back with the numbers when I've got them -- I read through the first five pages of the thread and didn't see it specified for the model/year -- and then search for an expert to do the work.

Yamae

I don't think your car stall during very hot sunny days is related to the ECU capacitors according to my experience. I'd rather think it's caused by the fuel pump itself or some other sensors which use a magnet like a crank position sensor. The most of sensor issues are detected by the ECU but the failed fuel pump is not always so. You can confirm the fuel supply issue using a fuel pressure gage or simply use the starting fluid.

You'd better read the code after those capacitors are changed and prepare what to do next depending on the result.

mjkwee

Yamae-San, Thank you for giving me a direction to investigate. The ECT sensor change certainly helped my car's performance. Can you help enlighten me about the possible wear of an ECT over time, and can this shift the resistance range causing extreme temperature readout? If the resistance range change on worn out ECT what does the ECU do if it detects the temperature is EXTREMELY HOT or beyond the elevated threshold? Does it shutdown the engine to prevent it from damage? Can a worn out ECT be a possible cause for a stall?

My '92 LS400 is over 21 years old and has about 185,000 miles. The stall occurs after driving the car on a very hot day on the highway running at speeds of 65-70mpg over 20+ miles. When the car begins to stall and pressing the gas pedal the engine does not respond or it feels like the carburetor is flooded. I wait and rest ~15 minute before starting the engine, it will start but momentarily stall again. Resting overnight, the car runs fine all day and several weeks. Would this be a sensor or more likely the fuel pump? One time after resting 15 minutes and I stepped on the gas pedal several times to give it more gas because I had to go over a ramp across the road. The car quickly surge instantaneously enough to get me over the ramp and it died again on the other side of the ramp. This just allowed me to make it home and i parked on the side of the street over night. The next day the car ran fine again. My problem is caused by elevated Temperature condition because the stall never occurred during cold or even slightly warm sunny day temperatures.

BTW, I read a thread were a member used the Chevron fuel system cleaner and it cured his stall. The last and recent stall incident my gas tank was close to empty. The next day I filled up my gas tank and added the Chevron Fuel System cleaner and the engine appear to run ok. Today, I also cleaned my MAF sensor in case it was dirty. It was a hot day and I drove on the highway. And made it home with no incident but I am nervous about the possible stall on a Hot day. The car ran fine and at one point i accelerated from 60 to 65 mph to shift lanes and the car surge nicely. FYI, my nephew notice there maybe a small leak on my coolant reservoir. I will have that check tomorrow.

Based on your post #8, can you comment on the difference between the Nippon Chemicon KZE versus KZH series capacitors? My post #896 i posted the capacitors I purchased from Digikey. The specs on these capacitors are not easily determined whether they are low ESR caps. May I request you feedback and confirmation on the caps I got are ok. I already used them on my replacement ECU but if I need to change any, i would want yo make sure when I update my original ECU to be the right one.

Your insights are much appreciated. Thank you again.

t2d2

iTrader: (8)

Here's what I've figured out so far for the '94 SC400 (ECU #89661-24231):

1) H9326 = 100μF - 10V
2) H9329 = 10μF - 50V
3) H9324 = (15μF - 35V?)
4) H9324 = (15μF - 35V?)
5) H9329 = 10μF - 50V
6) H9326 = 100μF - 10V
7) H9329 = 10μF - 50V
8) H9328 = (47μF - 63V?)
9) H9322 = 220μF - 16V

Edit, there's also a 10th one (47μF) tucked in below the thick metal bracing, alongside the pins from the wiring plugs.

Does anyone happen to know what H9324 and H9328 correspond to? I can't get a good enough angle to see what's printed on them, and I haven't seen those parts numbers in searches. Judging from the '94 LS400 specs in the first post, I'm guessing they're 15μF - 35V and 47μF - 63V, so I can probably just order a couple extra of each and be covered.

I found a local electronics guy who's experienced with ECUs, so I should be able to get it done pretty quickly once I have the new parts.

Edit: Using a small mirror, I was able to see what I'm pretty sure is a 47μF on the H9328 and a tiny little 25 or 52 or 35 or 53 on the H9324s (really tough to tell in reverse, at a terrible angle, and in tiny, interrupted print), so I'm guessing 15μF - 35V on those. That basically matches the LS400 of the same year. I went ahead and ordered double of everything, only $10 shipped from Digi-Key.

Yamae

I don't know much about the ECT sensor, but could you inform me the resistance at ambient temperature? Does it change when heated by a cigar or something similar?

Regarding the KZE, read the post #132 by LScowboyLS. The KZE is acceptable.

You were worried about the origin of the capacitors, but you don't need to do so. Many Japanese parts companies now have factories outside Japan and product qualities are still well controlled. Actually, I used to work in different countries to keep the quality of our products as good as made in Japan.

mjkwee

Yamae-San, Thank you for clarifying the capacitors series quality. I will try to do the ECT experimentation you suggested. It may take me a while to assemble a setup due to my disability, I lost motor coordination on my right side.

I scheduled to see my mechanic this afternoon and attempt to swap my ECU with the ECU with the modified caps. This will give me a known working i.e. "Good" ECU to further explore the Fuel Pump possibility. The capacitor change is a good idea regardless of other issues.

Yamae-San, I was concerned with the Japanese low-ESR made parts as repeatedly cautioned on page 1 by LScowboyLS. It shows how important it is to have the right parts. The caps I purchased are mostly manufactured outside of Japan. Thank you for sharing your experience working with offshore manufacturing. We are fortunate to have you here at the Club, the experience and knowledge you bring is invaluable.

Since my mechanic cost me and the garage $$ to debug my intermittent stall problem and twice my garage could not find the cause that maybe due to failing ECU caps. They have been very generous and helpful in my quest for a solution too. I am changing the ECU regardless because it is a time bomb waiting to happen with my 20+ years old LS400. I am lucky the problems have not shown up earlier. Does anybody know if the Fuel pump or the Fuel Resistor fails more than the other on the Lexus?

I am doing the research myself to keep my beloved LS400 with special adaptive equipment running a bit longer. I have been reading on the fuel pump thread https://www.clublexus.com/forums/ls4...problem-2.html with great interest.

Thank you again for your great insights....Michael

Update 7/31/14:
I swapped my ECU yesterday at my Garage. They were very generous with their time. The good news the car runs much smoother with the upgraded ECU with new Capacitors. The idling is much smoother and the car is responsive. I have my old original ECU. I have examined the insides and the capacitors are clean and there are no leaks. I intend to upgrade the Original ECU too after running my car for several days. Then this will become my spare ECU. My sad news my A/C is stuck because I disabled the A/C two years ago because my A/C compressor was not operating. This is my second compressor that lasted only 2-3 years. The replacement cost would have been expensive and the failure happened so soon. One symptom with the ECU capacitor problem is "No A/C compressor operation." So I requested they enable my compressor. I was told the compressor is stuck or the clutch maybe rusted. On top of that I must convert from R12 to R134. This process will require replacing my bad compressor or A/C clutch to get things running again then I need to convert to r134. My garage does not do the conversion. What are my options? Any suggestions? I need to bring this issue to another thread.

GoKeez

I'm experiencing the same issues with my 2003 ES300. Started seeing engine light a week ago. Few days later, the battery light appeared while running AC. Went to start and just heard clicking no turnover. Replaced battery and car started right up, cold AC, everything all good. 5 minutes later car shut off. I reset computer by touching pos and neg car started but idled to low and would shut off in park.

I managed to make it home by using neutral instead of park at lights. Next day, car started right up everything all good like new.

My question is how do I find the correct capacitors for my year and make, also should I replace fuel pump or idol sensor as well?