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Discussion Starter · #1 ·
Replaced all coil packs connectors value cover gaskets spark plugs & wires intermittent misfires that have how became consistent does not misfire sitting still or revving only driving & not all the time

I suspected 1st the connectors so I had taken it apart checked the clips since all of them were broke so I electrical taped (until my order came) as well as pressed down to makes sure all wires were snug on plugs, it drove good for a whole day (about an 1.5hr -2 hours of driving) then it came back again the next day after another 30 min of driving only intermittent replaced the clips
I suspected the coil pack so I removed it & replaced it with a known good one still came back

Timing has been good for 20k & the teeth match up also no timing codes it had a vacuume leak it is no longer throwing that code but then again I have erased it a few times to test the intermittent misfire

Can someone please help 馃檹馃徏
 

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Did you check the reluctor wheel on the crank? Also have you checked the crank and cam sensors? Have you checked the injector harness with noids to make sure it is firing the injectors. I know you have checked the connectors on the ignitor and coils.
 

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Cylinder 2 and Cylinder 5 misfire, dont they share the same coil pack? I would be wondering if there is something wrong with the coil pack, wires, connectors, leads, spark plugs, or even ignitor.
 

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Discussion Starter · #4 ·
Cylinder 2 and Cylinder 5 misfire, dont they share the same coil pack? I would be wondering if there is something wrong with the coil pack, wires, connectors, leads, spark plugs, or even ignitor.
Yes They share the same spark, I find it hard to believe 2 spark plugs went out at the same time or those 2 specific fuel injectors on the rail are malfunctioning do you know if 1 malfunctions, can it cause the connecting cylinder to misfire? Or would it only throw code for that specific injectors cylinder?

Maybe driving on a bad coil pack could have damaged the plugs? I am unsure, either way I have ordered 2 new spark plugs And I will be changing them in a few days & reorganizing the coil pack from 2&5-->1&6 as well as putting a new spark plug wire just to be 100% sure its not that
I do know it feels like a wiring issue since the code is not consistent would a bad ignitor cause this or MAF?
 

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Discussion Starter · #5 · (Edited)
Did you check the reluctor wheel on the crank? Also have you checked the crank and cam sensors? Have you checked the injector harness with noids to make sure it is firing the injectors. I know you have checked the connectors on the ignitor and coils.
I have not checked the reluctant wheel on the Crank
& I have a volt meter coming to check my harness but would one fuel injector really cause a connecting cylinder to misfire?
 

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but would one fuel injector really cause a connecting cylinder to misfire?
Unlikely. The ecu is very good at detecting individual cylinder misfire. Because the ecu knows crankshaft position with respect to time, it knows angular velocity. From there it can calculate angular acceleration on an instant to instant basis (calculus stuff - the first derivative of velocity is acceleration). The ecu fires the spark plug and watches for commensurate crankshaft acceleration on account of the combustion event.

Because #2 and #5 share a coil in waste-spark configuration, seems most likely to me you have an issue with the that coil or corresponding wiring.
 

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Discussion Starter · #7 ·
Unlikely. The ecu is very good at detecting individual cylinder misfire. Because the ecu knows crankshaft position with respect to time, it knows angular velocity. From there it can calculate angular acceleration on an instant to instant basis (calculus stuff - the first derivative of velocity is acceleration). The ecu fires the spark plug and watches for commensurate crankshaft acceleration on account of the combustion event.

Because #2 and #5 share a coil in waste-spark configuration, seems most likely to me you have an issue with the that coil or corresponding wiring.
This is what I'm thinking & since the car seems to be intermittent & not constant until more so recently I am being to suspect a short somewhere along the coil pack connectors im going to test that & the spark plug wire tonight

I feel hitting bumps may have finally where ever the wire was holding on together just gave out & may be causing a short
 

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Discussion Starter · #8 ·
Update i tested the coil packs & the connectors all read fine but when I took out the spark plug wire from the coil pack not only was it stuck but the connection was bent as if it were more of a
Diagonal--> /
instead of
straight up & down--> |

Does anyone know if this could cause the code?? I erased the code & drove it for a good 15 miles no blinking so far??
Do I have to drive 50 miles for the comp to read the misfire
 

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Yes the connection could be the issue. If it is running smooth with no misfire. That was the issue. That is why I said to check your connections.
 

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Discussion Starter · #11 ·
Yes the connection could be the issue. If it is running smooth with no misfire. That was the issue. That is why I said to check your connections.
Thanks
& thanks too all i appreciate the help

um this might be a dumb question 馃檭 are our vaulve covers supposed to be too hot to touch i remember touching them before & they seem hotter than I remember last 馃槄 but idk if I'm just high like I can place my finger on it for a moment but idk I dont have a temp reading thou
 

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At full operating temp, I'd say you should expect the valve cover to be ~160潞F. For me, that means I can press a fingertip against it with about 1lb of force for a little less than a second before it feels too hot to keep touching.

You've got 220潞 oil splashing against it, it's bolted to a cylinder head that is conditioned to run between 180 and 210, and it's got ~125潞F air being blown over it. You do the math.
 

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Discussion Starter · #13 ·
At full operating temp, I'd say you should expect the valve cover to be ~160潞F. For me, that means I can press a fingertip against it with about 1lb of force for a little less than a second before it feels too hot to keep touching.

You've got 220潞 oil splashing against it, it's bolted to a cylinder head that is conditioned to run between 180 and 210, and it's got ~125潞F air being blown over it. You do the math.
I guess thats about right
Math would read hot as tits thanks bruh
 

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Discussion Starter · #15 ·
They couldn't help said that I did just about everything they would recommend & that I could take it to a dealer for better insight of what's going on
 

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Discussion Starter · #19 · (Edited)
Did you fix that broken connection? Are you still getting the same codes?
I am & I really don't have money to go to a dealership I tried my mechanic he was honest said I did just about everything they would have suggested & since the timing has been good for a while its unlikely thats causing it , really only thing I can do is try fuel injectors &/or compression test but everyone says 1 fuel injector won't effect connecting cylinder i also hear all them clicking with no visible leaks
Not even sure if low compression would be intermittent I feel if it was low compression the light would come on as soon as erased
 

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Where did you get your spark plugs from? I have mentioned this very recently before in another thread. I replaced my neighbors plugs in his Honda with brand new NGK plugs and they literally failed within a week because they were counterfeit pieces. He was having p0300 codes and I noticed the plugs were completely shot after only a week of driving on them.
 
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