1997 LS400 170K miles, Coolant Leaks, alternator not charging, ...
02-11-16, 10:22 AM
#61
:::::::::::::typo deleted:::::::::::::.......=;o)....
Best you get that original ECU back in your car and let Lexus diagnose it and do the repair yourself.
PS: lots of repair manuals: http://lexus-doc.ru/..................here you will find 97 repair manual!!!
Parts cross-reference: look for toyo diy or .japan-parts.eu
Best you get that original ECU back in your car and let Lexus diagnose it and do the repair yourself.
PS: lots of repair manuals: http://lexus-doc.ru/..................here you will find 97 repair manual!!!
Parts cross-reference: look for toyo diy or .japan-parts.eu
Last edited by plexus914; 08-29-16 at 06:07 AM.
02-11-16, 04:11 PM
#63
Moderator
Your spare ECU (89661-50431) can not work, cause it is build date 07/1997-07/2000 (vvt engine that is / model years 98-00).
89661-50430 ECU is for build date: 10/1994-06/1997 (model years 95-97)
Best you get that original ECU back in your car and let Lexus diagnose it and do the repair later on yourself.
PS: lots of repair manuals: http://lexus-doc.ru/..................here you will find 97 repair manual!!!
Parts cross-reference: look for toyo diy or .japan-parts.eu
89661-50430 ECU is for build date: 10/1994-06/1997 (model years 95-97)
Best you get that original ECU back in your car and let Lexus diagnose it and do the repair later on yourself.
PS: lots of repair manuals: http://lexus-doc.ru/..................here you will find 97 repair manual!!!
Parts cross-reference: look for toyo diy or .japan-parts.eu
Is 89661-50430 for build date: 10/1994-06/1997?
02-12-16, 12:59 AM
#64
I finally fixed the engine (with an replacement). Also fixed the P1600 (bad trace on the ECU, fixed the capacitors as well). I notice a strange thing on the idle. Normally when turning on the AC or headlights, the car's idle should go up, but mine doesn't. Also the car dies when making a turn. Does this sounds like a vacuum or EUC issue? Sometime it dies when accelerating. Thanks in advance.
Have you checked air control valve (steering) yet?
AIR CONTROL VALVE
INSPECTION
1. TURN AIR CONDITIONING SWITCH OFF
2. CHECK IDLE–UP
(a) Start the engine and run it at idle.
(b) Fully turn the steering wheel.
(c) Check that the engine rpm decreases when the vacuum
hose of the air control valve is pinched.
(d) Check that the engine
rpm increases when the hose is released.
Last edited by plexus914; 02-12-16 at 01:13 AM.
02-16-16, 03:28 PM
#65
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@plexus914, Thanks for the info. I think the idle up is working. While I was trying to figure out why the car dies when it has warmed up, I removed the fuel pump relay to test the relay, to my surprise, the car runs without the fuel pump relay. What gives? Why the car runs without the FP relay. It restarts even when the car is warm. Thank you.
02-16-16, 03:58 PM
#66
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@plexus914, Thanks for the info. I think the idle up is working. While I was trying to figure out why the car dies when it has warmed up, I removed the fuel pump relay to test the relay, to my surprise, the car runs without the fuel pump relay. What gives? Why the car runs without the FP relay. It restarts even when the car is warm. Thank you.
02-16-16, 04:31 PM
#67
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Thank you for the explanation, Yamae. So, potentially when the car is under load, the car may stall or die when the FP relay is defective then. So does a defective FP relay cause hard or no starting?
02-16-16, 07:32 PM
#68
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No. Under the heavy load, the car doesn't run as you expect and seldom stalls.
03-21-16, 01:07 PM
#69
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A quick update: I replaced the fuel pump. The car won't die any more, instead it stalls when making a turn or when braking it to stop the car. My next job is to clean the IAC Valve (Idle Air Control Valve). Any other ideas? Thanks.
03-31-16, 12:24 PM
#70
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Well, I was going to check the IAC valve, Then the car experienced misfire (P0306). The misfire was intermittent. The check light would blink. Last night, the check light was blinking and it was really dragging. it refused to accelerate. It recorded the code of P0306. Another strange thing was that If I shutdown and restarted right away the check engine light was still on. After 1 hour when I restarted the car the check engine light disappeared and error code was gone. It seems the problem was on ECU? A little history on the ECU, I replaced all the capacitors according to LSComboyLS (https://www.clublexus.com/forums/ls-...capacitor.html). One trace was damaged, which was causing P1600 error). I repaired with a conductive pen and the P1600 is gone. I am thinking my ECU is still not 100% healthy. I am attaching a few pictures of my ECU.
Last edited by ychen; 03-31-16 at 12:28 PM.
03-31-16, 03:47 PM
#71
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At the third photo, it seems to me that the capacitor 200uF/50V is reversed. The negative side of the capacitor's lead wire seems to be soldered to the hole marked +. This capacitor has an important role to remove the ripple for the Vcc line and the reversed mount causes problems.
03-31-16, 08:40 PM
#72
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Thank you sire, Yamae for your prompt reply. I think the polarity is correct. I made sure the polarity of the capacitor match the old one when I was replacing the capacitors. In fact, I found all capacitors on the ECU have their negatives pointing to one same side and the positives point the other same side. The positive sign you saw was for the C131 (the smaller blue one). I do have a question on the repaired trace. The repaired trace has about 25Ohm, where the original copper trace has almost 0Ohm. Would that cause a problem? This trace gets the power from the battery.
03-31-16, 09:01 PM
#73
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Thank you sire, Yamae for your prompt reply. I think the polarity is correct. I made sure the polarity of the capacitor match the old one when I was replacing the capacitors. In fact, I found all capacitors on the ECU have their negatives pointing to one same side and the positives point the other same side. The positive sign you saw was for the C131 (the smaller blue one). I do have a question on the repaired trace. The repaired trace has about 25Ohm, where the original copper trace has almost 0Ohm. Would that cause a problem? This trace gets the power from the battery.
25ohm is too big for the DC power line, I must say. You'd better connect the damaged trace using a copper wire with solder?
08-12-16, 01:59 PM
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Hello, My 97 LS400 still doesn't store OBDII info even after I soldered a copper wire. BTW the P1600 error code is gone. I would like to iterate the problem: It could not store any error codes. After I shut off the engine, all the error codes (or pending codes) disappear. Any thoughts? Thanks.