P0301 And P0305 Cylinder Misfire Error

[749_dark]

Greetings,

2 main questions:

1) A couple days ago the engine starting running a little rough. A few hours after I started noticing my CEL went on and my traction control light started flashing. Went to discount and retrieved error codes P0301 and P0305, cylinder 1 and 5 misfire. 2002 Lexus IS300, 5-speed manual, 92k miles, performed 30k tune-up at 70k using bosch platinums for the plugs. Any ideas/recomendations are greatly appreciated.

2) The car will be in the shop for a new timing belt, accessory belt, and water pump (friend recommended I do the water pump along with the timing belt). thoughts? What about the fuel filter? I remember changing it on my nissan pickup every 15k.

Thanks,

-A

[djspawn00]

possible bad coil pack? maybe a leaky VCG causing the misfire? I can't really say.. but as far as the 90k service goes, timing belt should always include the water pump... maybe the crank seals and tensioner as well. Maybe someone else can chime in the the CEL.

I would also recommend the OEM plugs over the Bosch. Denso or NGK Iridiums I believe... if you're gonna go aftermarket i'd say torquemasters....

[lenore]

Greetings,

2 main questions:

1) A couple days ago the engine starting running a little rough. A few hours after I started noticing my CEL went on and my traction control light started flashing. Went to discount and retrieved error codes P0301 and P0305, cylinder 1 and 5 misfire. 2002 Lexus IS300, 5-speed manual, 92k miles, performed 30k tune-up at 70k using bosch platinums for the plugs. Any ideas/recomendations are greatly appreciated.

2) The car will be in the shop for a new timing belt, accessory belt, and water pump (friend recommended I do the water pump along with the timing belt). thoughts? What about the fuel filter? I remember changing it on my nissan pickup every 15k.

Thanks,

-A

Yep, dump those bosch plugs, I have had terrible luck with them on multiple vehicles (honda, mercedes, ford) Go back to Denso or NGK and you will be happy.....Hope the plugs didnt wipe your two coil packs......Please trust me the bosch plugs are garbage....one man's opinion....also the same opionion from the son-in-laws brother who runs a speedylube.....

[smooth1]

Greetings,

2 main questions:

1) A couple days ago the engine starting running a little rough. A few hours after I started noticing my CEL went on and my traction control light started flashing. Went to discount and retrieved error codes P0301 and P0305, cylinder 1 and 5 misfire. 2002 Lexus IS300, 5-speed manual, 92k miles, performed 30k tune-up at 70k using bosch platinums for the plugs. Any ideas/recomendations are greatly appreciated.

2) The car will be in the shop for a new timing belt, accessory belt, and water pump (friend recommended I do the water pump along with the timing belt). thoughts? What about the fuel filter? I remember changing it on my nissan pickup every 15k.

Thanks,

-A

Yep, Bosch plugs are no good in these cars. You need Denso, or NGK. Denso's are a much better plug though, and get the irridiums. they cost more, but you get alot more for it. The water pump and belt, tensioner, and timing should all be done at the same time because you have so much labor involved to get to them, it's cheaper to be safe while your there. You shouldn't have to replace your fuel filter. It's inside the fuel tank and I haven't ever needed to replace one.

[749_dark]

10-4 on the water pump and belt, tensioner, and timing all on the same project. I'm also ordering new spark plugs, growing overseas, I always was lead to believe that Bosch german parts are the best. Just to confirm denso part# for my 2002 IS300 for the iridium: SK16R-P11.

On the CEL: any recommendation on what I should try first (makes the most sense to try first). Where can I pickup coil pack or the VCG? I'm taking the car to a mechanic for all the timing belt stuff (uses Lexus factory parts), any information I could give him to debug the CEL will be very helpful to him and to my wallet.

Coil Pack question (apologies for my ignorance): is there one for each bank or one for each cylinder. If we determine that the coil pack is bad then do we replace just the bad ones or all of them (assuming they are one per cylinder).

Thanks for the help.

[smooth1]

10-4 on the water pump and belt, tensioner, and timing all on the same project. I'm also ordering new spark plugs, growing overseas, I always was lead to believe that Bosch german parts are the best. Just to confirm denso part# for my 2002 IS300 for the iridium: SK16R-P11.

 Yes, and the gaps are .044 make sure you get that right! .044 is a huge gap compared to most others. Which is why the Bosch plugs don't work very well.

On the CEL: any recommendation on what I should try first (makes the most sense to try first). Where can I pickup coil pack or the VCG? I'm taking the car to a mechanic for all the timing belt stuff (uses Lexus factory parts), any information I could give him to debug the CEL will be very helpful to him and to my wallet.

 I would just clear the cel with an ODB II scanner after you change the plugs. most auto Zones will do it for free. You should be good to go.

Coil Pack question (apologies for my ignorance): is there one for each bank or one for each cylinder. If we determine that the coil pack is bad then do we replace just the bad ones or all of them (assuming they are one per cylinder).

 It's an inline motor, so there is only one bank, but the coil packs charge 2 cylinders each. I honestly think once you change your plugs back, you should be fine though.

Thanks for the help.

[749_dark]

Smooth-I think you're right (not surprising)

I got into my car this afternoon and no more rough idle and no more CEL/trac light flashing. I got the Denso plugs, summed up my courage and started ripping parts of to try and get to my spark plugs, well...45 minutes later (I'm not mechanically inclined so it takes me a little longer to get to things), there was a puddle of oil around the bottom of the plugs and the plugs themselves were all oily.

cleaned the oil, replaced the plugs, and all is well.

Thanks again for the help!

-A

[djspawn00]

Smooth-I think you're right (not surprising)

I got into my car this afternoon and no more rough idle and no more CEL/trac light flashing. I got the Denso plugs, summed up my courage and started ripping parts of to try and get to my spark plugs, well...45 minutes later (I'm not mechanically inclined so it takes me a little longer to get to things), there was a puddle of oil around the bottom of the plugs and the plugs themselves were all oily.

cleaned the oil, replaced the plugs, and all is well.

Thanks again for the help!

-A

That puddle of oil around your plugs could be from a leaky valve cover gasket... not hard to change if you managed to change your plugs without problem.

[smooth1]

Smooth-I think you're right (not surprising)

I got into my car this afternoon and no more rough idle and no more CEL/trac light flashing. I got the Denso plugs, summed up my courage and started ripping parts of to try and get to my spark plugs, well...45 minutes later (I'm not mechanically inclined so it takes me a little longer to get to things), there was a puddle of oil around the bottom of the plugs and the plugs themselves were all oily.

cleaned the oil, replaced the plugs, and all is well.

Thanks again for the help!

-A

That puddle of oil around your plugs could be from a leaky valve cover gasket... not hard to change if you managed to change your plugs without problem.

Right, if the oil was around the insulator, then it's just the valve cover and is easy to fix as djspawn mentioned. If the oil you referred to was on the electrodes, then that is just a sign they were fouled out and no longer firing, which is why you got the cel light, misfires and so on. I would have expected to see that. Do a few second gear strong acceleration pulls to almost redline. That will help blow out any carbon you may have accumulated during the fouled plug fiasco. And run a few tanks of fuel with some Techron or some fuel system cleaner that you like to use.

[749_dark]

I had my appointment for the timing belt/water pump/etc today...so the car is at the shop. I think it's the seal, two much oil around that inside center area. I asked the mechanic to replace it. I'm happy it's not coils or any other expensive sounding stuff. I'll run the fuel system cleaner when I get the car back.

appreciate all the advice.