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2004 5-speed, w/ LSD & Sport package 馃槑
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Discussion Starter #1
Okay, so here's my tale of sorrow...

when i first got my 5 speed IS, i thought it was running fine. Yet, somehow there was popping on idle. I didn't think much of it. I then proceeded to buy cheap chinese coilpacks, and they eliminated any and all popping, however, they quit after only about 4 months of use. I then manned up and overhauled most of my ignition system: New OEM denso coilpacks, NGK plug wires, and new replacement connectors, yet i still have a misfire in 1st gear when i go to 50% throttle it after it's idling (while moving in 1st gear, i don't know if i explained myself well there). I made sure my pins are in the right spot, and that i didn't swap any plug wire locations over to where they don't go (coilpack #3's plug wire goes to cyl 6, coilpack #1's wire goes to cyl #5, and coilpack #2's wire goes to cylinder 3). Has anybody had a similar issue? My old coil packs are slightly worse than the newer ones, with a more noticable misfire at idle. I'm running out of options as to what's wrong... Since I have an '04, my igniter is a DH61, so should i try replacing it? if so, would a used one be a safe bet? I'm not very knowledgeable when it comes to diagnostics with misfires besides "unplug that injector and see if it still misfires" kind of diagnostics. Also, This is my first post here, so please go easy on me if i did something wrong.
 

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Okay, so here's my tale of sorrow...

Has anybody had a similar issue?
I'm currently battling something similar, however my misfires can creep into either gears depending on the load. I have to evaluate my sound system though, maybe you have one too?


Since I have an '04, my igniter is a DH61, so should i try replacing it? if so, would a used one be a safe bet? I'm not very knowledgeable when it comes to diagnostics with misfires besides "unplug that injector and see if it still misfires" kind of diagnostics. Also, This is my first post here, so please go easy on me if i did something wrong.
I've been curious to see if replacing the ignition module would help my case as well, however I don't know enough about it's function to know if it will solve the problem at all. The only thing you haven't talked about was the spark plugs. If you take a look at their condition on the cylinders that are causing your problems, the way they look can reveal a lot about how they're performing.

As for your first Help and Repair post, seems fine, maybe a little better formatting instead of a wall of text, and list CEL codes if available as solar mentioned.
 

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I think i read somewhere recently it supposed to be 5 & 2? (not sure of the others)
 

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2004 5-speed, w/ LSD & Sport package 馃槑
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79 Posts
Discussion Starter #7
I'm currently battling something similar, however my misfires can creep into either gears depending on the load. I have to evaluate my sound system though, maybe you have one too?




I've been curious to see if replacing the ignition module would help my case as well, however I don't know enough about it's function to know if it will solve the problem at all. The only thing you haven't talked about was the spark plugs. If you take a look at their condition on the cylinders that are causing your problems, the way they look can reveal a lot about how they're performing.

As for your first Help and Repair post, seems fine, maybe a little better formatting instead of a wall of text, and list CEL codes if available as solar mentioned.
Yes, thank you so much for all the awesome feedback. I did the sparkplugs (replaced with NGk laser Iridium plugs) about 400 miles ago
 

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2004 5-speed, w/ LSD & Sport package 馃槑
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79 Posts
Discussion Starter #8
If you're referring to the wiring order for the coil pack configuration, it's 1/6, 5/2, 3/4, with the actual firing order being 153624
Yep, that鈥檚 exactly what i meant, since our cars work on waste spark. Kinda ingenious actually
 

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Yes, thank you so much for all the awesome feedback. I did the sparkplugs (replaced with NGk laser Iridium plugs) about 400 miles ago
So I can't say that your choice of plugs should be giving you such serious problems; however I do know that Toyota chose double tipped Iridium Denso plugs as the right one for these engines in stock configurations. I want to say this is mainly for longevity, but it could have something to do with spark performance. P/N: SK16R-P11 (if you want to look into them)

Continuing on about my statement about the spark plugs and their condition if you pull them to see how they're looking, here's a quick guide on what i'm referring to if you've never seen it before:

136439



This way you can dial it down to a single, or exactly which cylinders are under-performing.
 

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2004 5-speed, w/ LSD & Sport package 馃槑
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Discussion Starter #12
I feel I must come out and say that misfires are ALSO fuel related. A bad fuel injector can cause misfires as much as a bad coil pack could.
I appreviate the tip, but I already know for a fact that it's not my injectors, as the misfire doesn't occur above 2000 RPM in ANY gear. It actually seems to have more power somehow.
 

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2004 5-speed, w/ LSD & Sport package 馃槑
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Discussion Starter #13
Do a compression check. Could have had a bent valve.
Somehow not a bent valve either, although the other day I money shifted into 2nd trying to go into 4th on a corner. I chirped the tires a bit, but pushed the clutch in as fast as i possibly could, and pulled over to check for any knocks or ticks. Nothing at all. I think my rev limiter stepped in and helped me out MAJORLY there.
 

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2004 5-speed, w/ LSD & Sport package 馃槑
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Discussion Starter #14
So I can't say that your choice of plugs should be giving you such serious problems; however I do know that Toyota chose double tipped Iridium Denso plugs as the right one for these engines in stock configurations. I want to say this is mainly for longevity, but it could have something to do with spark performance. P/N: SK16R-P11 (if you want to look into them)

Continuing on about my statement about the spark plugs and their condition if you pull them to see how they're looking, here's a quick guide on what i'm referring to if you've never seen it before:

View attachment 136439


This way you can dial it down to a single, or exactly which cylinders are under-performing.
This is a great idea, I'll pull the plugs later today and update you on how they're doing. Thank you for all your help, Especially 01_Solar_Yellow and ill_mannered
 

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I feel I must come out and say that misfires are ALSO fuel related. A bad fuel injector can cause misfires as much as a bad coil pack could.
I personally wonder if this is contributing to my issues. Is it possible for injectors to become fouled like spark plugs do? Or is it that their internal screen filters get clogged up?
 

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2002 Lexus IS300
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I personally wonder if this is contributing to my issues. Is it possible for injectors to become fouled like spark plugs do? Or is it that their internal screen filters get clogged up?
Yes. Very possible. They are also mechanical items that sometimes simply quit working.
 

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2004 5-speed, w/ LSD & Sport package 馃槑
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Discussion Starter #18
Yes. Very possible. They are also mechanical items that sometimes simply quit working.
The only problem i see here is that to take out the injectors, you have to take out the entire upper intake manifold... Not gonna do THAT again
 
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