[ray]

Bought a new fuel cap, check all connections and hoses.

The engine light still came on. I recently replaced a harness clip on the Cylinder 1 ignitor coil.

I am leaning towards the ignitor coil being the issue.

[ray]

Bought a new fuel cap, check all connections and hoses.

The engine light still came on. I recently replaced a harness clip on the Cylinder 1 ignitor coil.

I am leaning towards the ignitor coil being the issue.

[ray]

The latest and greatest…

I had a harness clip loose on one of the ignition coil packs (namely Cylinder 1).
Ever since I had the harness clip replaced the check engine light has never returned.

Even though it threw a P0440 code, could it have all been caused my a slight misfire or circuit issue caused by the harness clip being loose?

Would like to think this engine light will never light up again for this reason…

Let me know what you guys think….

[ray]

The latest and greatest…

I had a harness clip loose on one of the ignition coil packs (namely Cylinder 1).
Ever since I had the harness clip replaced the check engine light has never returned.

Even though it threw a P0440 code, could it have all been caused my a slight misfire or circuit issue caused by the harness clip being loose?

Would like to think this engine light will never light up again for this reason…

Let me know what you guys think….

[ray]

Hey guys…

Karl you were right it is a waste spark system, first off. I totally forgot I have the additional spark plug wires running to the back of the engine.
Had a diagnosis done on it with the local mechanic to ensure the theory is correct and received the car back a few hours later only needing to replace the harness connector that clips onto the ignition coil pack. It was moving around and accruing moisture.

***Attention, Lexus Owners*** Do not bother calling Lexus for the replacement harness clips because the dealer will try to sell you a whole harness and wiring assembly upwards of $100 bucks. I went to my local Wrecking Yard and grabbed as many as I could find beside the one I needed for the job. Only paid about 5 bucks.

Spliced the wiring, made sure to tightly wind the electrical tape to protect the wiring and popped the new connector on. Runs smooth as butter and starts up like she normally does. Guess it did turn out being something funny like a little electrical issue.

From an experience standpoint, I would say just before going to any extreme, check connections. Check wiring. And use the tactic ToyotaKarl mentioned in the middle of the thread. I went to my local mechanic because I needed to make sure that it was nothing else causing the problem. This series of steps (maybe minus taking your car to a shop) should solve your issue if your running into this problem – generally if you pull a P1300 code.

I hope this topic helped those with an issue where their Lexus ES300 isn’t holding idle!!!

Have fun, guys…

Attachments:

• images.jpeg

[ray]

Hey guys…

Karl you were right it is a waste spark system, first off. I totally forgot I have the additional spark plug wires running to the back of the engine.
Had a diagnosis done on it with the local mechanic to ensure the theory is correct and received the car back a few hours later only needing to replace the harness connector that clips onto the ignition coil pack. It was moving around and accruing moisture.

***Attention, Lexus Owners*** Do not bother calling Lexus for the replacement harness clips because the dealer will try to sell you a whole harness and wiring assembly upwards of $100 bucks. I went to my local Wrecking Yard and grabbed as many as I could find beside the one I needed for the job. Only paid about 5 bucks.

Spliced the wiring, made sure to tightly wind the electrical tape to protect the wiring and popped the new connector on. Runs smooth as butter and starts up like she normally does. Guess it did turn out being something funny like a little electrical issue.

From an experience standpoint, I would say just before going to any extreme, check connections. Check wiring. And use the tactic ToyotaKarl mentioned in the middle of the thread. I went to my local mechanic because I needed to make sure that it was nothing else causing the problem. This series of steps (maybe minus taking your car to a shop) should solve your issue if your running into this problem – generally if you pull a P1300 code.

I hope this topic helped those with an issue where their Lexus ES300 isn’t holding idle!!!

Have fun, guys…

Attachments:

• images.jpeg

[ray]

So Karl…

Got a call from the mechanic earlier and he was relieved enough to say that the issue arose from the harness/wiring from the front cylinder, first on the left. Apparently it was causing an issue with another cylinder and it is…(you guessed it) a waste spark setup.
So all I have to do is replace a bad connector which apparently caused the whole problem.

So what I will do tonight is splice into the existing wires and clip the new connector on. From there I will let you guys know how it all goes from there. Thanks for the advice that hopefully let to a successful result.

Have fun guys!

[ray]

So Karl…

Got a call from the mechanic earlier and he was relieved enough to say that the issue arose from the harness/wiring from the front cylinder, first on the left. Apparently it was causing an issue with another cylinder and it is…(you guessed it) a waste spark setup.
So all I have to do is replace a bad connector which apparently caused the whole problem.

So what I will do tonight is splice into the existing wires and clip the new connector on. From there I will let you guys know how it all goes from there. Thanks for the advice that hopefully let to a successful result.

Have fun guys!

[ray]

Thank you for going to great length to explain that to me. So the 1 3 5 cylinders do not have a coil pack and just run off of the auxiliary wires from 2 4 6?

Thanks for the help!

[ray]

Thank you for going to great length to explain that to me. So the 1 3 5 cylinders do not have a coil pack and just run off of the auxiliary wires from 2 4 6?

Thanks for the help!

[ray]

I am also confused when you say 4 is tied in with 1…what does that mean?

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I am also confused when you say 4 is tied in with 1…what does that mean?

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I just decided to take it to my local shop and let them scan it. I would love to use the coil pack to test the other cylinders but in this case cylinder one is against the firewall underneath a plenum and throttle body.

I figure I let them tell me what it is, I lift the plenum then do the work. I would imagine there is some labor involved and that would shoot the cost thru the roof. I just hope it plays out to be that simple. Otherwise their diagnosis may require going beyond the surface.

Thanks guys…I will let ya all know what happens.

[ray]

I just decided to take it to my local shop and let them scan it. I would love to use the coil pack to test the other cylinders but in this case cylinder one is against the firewall underneath a plenum and throttle body.

I figure I let them tell me what it is, I lift the plenum then do the work. I would imagine there is some labor involved and that would shoot the cost thru the roof. I just hope it plays out to be that simple. Otherwise their diagnosis may require going beyond the surface.

Thanks guys…I will let ya all know what happens.

[ray]

So i went to the local parts retailer who pulled the codes off my CEL.
Apparently it is an issue involving P1300.

Code definition is cylinder #1 IGf signal does not return from ignitor. This is strange as the car runs smoothly and shows no obvious runability issues. Could this be a coil pack problem? Whatever the case I am letting my local shop run a scope on it to ensure I fix the right thing.

Any guidance from here would be much appreciated as I am not too sharp with electrical and would love to save a trip to the shop…

Thanks guys!!!

[Author]

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