My Lexus has acted up....

[paulo57509]

I have a 26 year old Lexus LS400. About 8 years ago it started running poorly. I checked everything I could think of and the codes I got varied from one thing to another. I decided to check the ECU (computer). I removed it from under the dash (glove box area), opened it up an saw where there was a tobacco like juice running out of one of the capacitors onto the circuit board. There were six capacitors on the board. I View attachment 133238 ordered all six from DigiKey, cleaned up the board and replaced the capacitors. Problem solved for $7.00.

You were lucky the leakage didn't get in between the PCB layers. Once that happens, it's game over for the ECU.

All my crazy Lexus issues SOLVED!! (ECU-leaking capacitor) - ClubLexus - Lexus Forum Discussion

LS - 1st and 2nd Gen (1990-2000) - All my crazy Lexus issues SOLVED!! (ECU-leaking capacitor) - 430230 *photo courtesy of distinguished Japanese ECU engineer Yamae 430231 IMPORTANT: The capacitors may look perfectly fine and yet be bad, they look great at first, then deteriorate and cause damage...

www.clublexus.com

 

[meep]

Is this a timing belt or chain vehicle?

i start with plugs, then check coils. If the problem moves around, that’s harder. if it’s widespread, things like wiring harness, fuel mixture and related sensors, carbon buildup and ECU get suggested. I had a misfire issue on a Subaru that favored one cylinder, but after new coils, wires, and plugs, it moved. Turned out to be a timing belt which had stretched (non-oem) in about 30,000 miles of use. I didn’t realize this was the cause, but a water pump replacement forced a new belt and that fixed all the misfires. The belt was notably stretched longer upon inspection.

 

[dblshock]

I ordered the coil for cylinder #3...my confidence level has diminished though.

 

[researcher]

hmm.. odd you're playing "whack a mole".. is this more of the replace all of them sort of thing? Definitely keep us updated on what happens when you replace #3.

 

[dblshock]

have to 'whack a mole' these coils are $80-$100ea. at the dealer but $26 Genuine Toyota on E.bay, problem with that they're from CA. so like 5 days freight time...also Denso # 6731303.

 

[Gebo]

I don't know if this applies to you but make sure they are coil clips are fully clipped in and snug. The little plastic tabs that lock them are very easy to break. If one is slightly loose it may be why it seems to be intermittent and/or only happens under load. I use zip ties to hold my connector clips tight against the coil packs.

Also, I have very little confidence in any auto parts purchased on eBay. I'd get one from a dealership and do the swapping around
after checking my connections.

My Blue Driver sometimes takes several cycles before it shows a code. However, it shows "Pending" pretty quick.

 

[dblshock]

Success ... After replacing #1 coil that code moved to cylinder #3 right next to #1 so replaced #3 coil and the misfire codes are now gone however, I'm left with a pending code: Catalyst System Efficiency Below Threshold Bank 1... thinking it was tainted by the earlier misfires and will clear out now all that has been corrected...but running strong again.

Repair cost $52.00

 

[Gebo]

Great!!!

 

[researcher]

Success ... After replacing #1 coil that code moved to cylinder #3 right next to #1 so replaced #3 coil and the misfire codes are now gone however, I'm left with a pending code: Catalyst System Efficiency Below Threshold Bank 1... thinking it was tainted by the earlier misfires and will clear out now all that has been corrected...but running strong again.

Repair cost $52.00

awesome to hear! so it wasn't so much whack a mole but two of the coils were bad. not bad for $52!

 

[dblshock]

got a little day trip up 125mi. to Ontonagon, MI. today mostly thru national/state forest not much development anyway I'm taking the 4Runner because my confidence isn't quite back yet after only 6mi. on the coil repair which was only 2 of 8 replaced....being retired I have time to play this out hopefully.

 

[Gebo]

C’mon, live on the edge. You may as well put your baby to the test.

Just make sure you got cell service in the forest

 

[palmerwmd]

My vehicle is not a Toyota but on a similar age/milage Nissan V8 SUV those exact symptoms would be crankshaft postion sensors 95% of the time.

 

[dblshock]

C’mon, live on the edge. You may as well put your baby to the test.

Just make sure you got cell service in the forest

You'd be lucky to get satellite reception then someone to pick-up your call.

 

[dblshock]

My vehicle is not a Toyota but on a similar age/milage Nissan V8 SUV those exact symptoms would be crankshaft postion sensors 95% of the time.

I believe they got a OBD code for that, no?..never a crank code here.

 

[palmerwmd]

I believe they got a OBD code for that, no?..never a crank code here.

Yes there is a code for that camshaft position sensor and for the crankshaft postion sensor (also).
But its not always 100% reliable to be tripped correctly im my experience.

Anyway, just throwing it out there. its not an expensive part for a DIYer to put in.

 

[Hillbilly Deluxe]

Everybody afraid of a Toyota …. Cause they don’t have to fix 100 of them a day, 5 days a week….

 

[meep]

catalyst error could clear up. He’s been having to deal with incomplete combustion and more fuel than usual, getting dumped into the exhaust. Might benefit from a fuel system cleaner and some spirited runs of acceleration to heat them up and blow stuff out.