My Lexus has acted up....

The problem with diagnosing a coil seems to be the engine starts and idles perfect...my BlueDriver and the shop scan show no engine codes.

I have the time to buy one or two coils then over days just keep switching the old ones out til I find the bad one.
 
this truck is full time 4WD only option is H/L...
Not related to torque convertor.

Can you drive around with your reader and can it read more than just codes? I’d think a misfire would have to flag something somewhere on a monitor.
 
Not related to torque convertor.

Can you drive around with your reader and can it read more than just codes? I’d think a misfire would have to flag something somewhere on a monitor.

I can and BluDriver has Mode 6, live options (fuel status) and MIL Status?
 
I have a 3UZ-FE and find it funny that for an emissions issue, Check VSC lights up and there's no traction control. The two codes I've experienced are misfire and front pass 02 sensor. Again reading the codes are crucial, everything else guessing, if no codes, then the next step is dealer software? Not all readers read all codes from my limited experience...my .02
 
I ordered one new OEM coil..$26...a rev in neutral produces very little stumble initially and zero after that.
 
Is this a V8 (I believe so). I had always heard on the forum that my car, when serviced by the dealer, quite often ends up with only 7/8 plugs changed (as evidenced when a shade tree DIYs), because the dipstick tube obstructs cyl #1 (driver side front). Could that be the culprit....when I did mine at 118k they looked factory/never done yet.
 
If you have the time and patience moving your one new coil through all 8 cylinders makes sense. If, at the end, it doesn’t make a difference, well, you only bought one.
 
I haven’t chased one of these in a long time. I did have an obd2 Subaru that developed a misfire just like this as one of the plug wires began to arc to ground. It did not throw a code at first, only when it got really bad. He might not have codes stored on it yet.
 
all 8 plugs were replaced with oem by me 30k ago. engine starts right up and idles perfect, revs fine from neutral, problems start once a load is placed on the system especially if it's just a subtle increase the stumble is obvious.
 
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
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ordered all six from DigiKey, cleaned up the board and replaced the capacitors. Problem solved for $7.00.
 
Have the coil boots ever been replaced? In the absence of codes, pull the coils and inspect the boots for high voltage leaks and damage. It's really common for people the replace multiple sets of plugs, but not do the boots and eventually their fit isn't as good and HV comes shooting out and down the side of the plug
 
I have a Sequoia with the same 4.7 with 208k. I replaced the plugs and coils with OEM Denso (yes it was $$) due to an occasional misfire under load. The coils were original and were starting to break down (pretty brown in color on the boots). Plugs were worn but still usable. After the swap no more issues and it runs fantastic. It's a common issue on these 4.7's around 200k miles.
 
Yes..Just a couple hours ago BlueDriver got a code 0301... Cylinder 1 Misfire Detected

2 Frequently Reported Fixes
• REPLACED SPARK PLUG • REPLACED DIRECT IGNITION COIL (IGNITION COIL)
 
Update....

New OEM coil installed on #1 per code, test drove problem still observed,
ran a scan misfire code again but moved to cylinder #3. What next?
 
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