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p0303 /p0302 codes , rough idle after timing change

446 Views 41 Replies 6 Participants Last post by  notsonerdy
I had a code to change the timing chain, (p0341) when I looked it up, a common response was chain was stretched

just changed the timing chain, checked timing, re pinned the cams - everything lines up

vtc gear wasn't changed, stock spec

now I have p0303 stored code ( flashing check light). car runs very rough, eventually dies

moved the coil pack from 3 to 4 and got 0302 (cylinder 2), so I got all new coil packs

back to p0303 stored

would a bad valve lash cause this? would the cam position when changing the chain effect the lash

changed the crank angle sensor to an older one I have and now its p0302

I did the "dollar bill" test and the bill was flapping

takes a lot of cranks to start- could be due to failing starter

pulled the plugs- from left to right

1- half fuel fouled

3- fuel fouled

4 - fuel fouled

2 - extremely fuel fouled

put in a new set of plugs, cleared the ecu by grounding the positive and negative lines for 10 minutes ( off battery) and now code 0303

changed primary 02 - code 0303 pops about 1min into running , runs better but dies quicker

ive only tested cyl 1 intake lash and they are very tight, I'm assuming there are others that are tight

lashed all of them, car runs better, doesn't die, but still throws 0303 and 0302 alternating every time I turn on the car

car still takes time to crank and the last cylinder on the driver side is fuel fouled
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adjusted lashes, they were in pretty good shape except for the last cyl by the driver side ( cyl 2)

still runs rough but way better

now throws p0303
Have you compression tested the motor? If compression is OK on all cylinders then you gotta start looking at things that can cause individual cylinder misfires. Check Plugs, coils, injectors, wiring, ecu for a start.
still runs rough but way better
Looks like your off a tooth on the cam gear pic. Granted it couldn't be that simple.
how could it be off if the cams are locked
how could it be off if the cams are locked
Cams are locked with pins in your first picture? I do agree, they look off a bit.

last cyl by the driver side ( cyl 2)
Am I misunderstanding you or are you confused with the cylinder numbering? Cylinder 1 is on the timing chain side, increasing sequentially to cylinder 4 on the trans side. The last cylinder on the driver's side is cylinder 4.
cams are locked , it does look off, but ive read that its common that they look off

there should be 8 links between the dots on k24's

cylinder sequence is 1342?

im getting p0302 now, so its just switching back and forth from 02 to 03 misfire codes
The firing order is 1-3-4-2 but the cylinder order is 1-2-3-4 (timing chain side -> transmission side). Start swapping coil packs, spark plugs, and injectors between cylinders to see what the misfire follows.
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already did, check out the opening post

could the vtc be bad without throwing a code or make a rattle sound
already did, check out the opening post
You haven't touched injectors unless I'm missing something.
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misfires switch from 02 to 03 randomly

car worked fine before the chain change, im going to check the vtc , thats the variable
vtc moved

I'll fix it tomorrow
I'll fix it tomorrow
Let us know. Keep in mind you came to bonce this off us. The angle of the pic the lighting, my butt itches can all effect the out come of our trying to help you. Being a tooth off can happen to anybody. So can not properly locking in the VTC. Not that hard to lock it in and what are the odds of it moving once it's locked?
Ok. Sorry.. WTH is the dollar bill test lol?
same issue

rechecked timing good

got p0011 once, cleaned it up and put it back in

back to p0302

4th cyl plug is wet but not dripping... its definitely running rich, but prob because the code
Ok. Sorry.. WTH is the dollar bill test lol?
I read that putting a dollar bill behind the muffler - that if it sucks and holds it in, its bad valves
the timing mark lines up but the cam lines still look off, went to the back of. the cam and it looks like the pin hole is off

there are links between the two cam dots , which were highlighted on the chain .... should I have moved it one link back

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or could this new chain possibly be stretched
I also tested spark and all 4 arc, but its very weak
Somebody correct me if I'm wrong but I'm pretty sure the cam dots should be in the middle of a link, not in between them

Edit again: this diagram and description is for the k20, not the k24. We should be discussing the k24
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