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Discussion Starter · #1 · (Edited)
I have a bad misfire on cylinder 2, Ive replaced my spark plugs again just last night. I swapped a known good ignition coil from cylinder 1 to cylinder 2 and the code didn't change from P0302 to P0301. I even did the test where you unplug the coils while it's running and each cylinder except no. 2 changed the idle when unplugging the coil. And that's with the coil from cylinder 1 which was working before I swapped them. Next step I guess would be the wiring but i don't see any immediate issues with the wiring it's not torn and the ground cable on the valve cover in tightened down. I did pull my spark plugs last night and even though I replaced them last year cylinder 2 and 6 both looked fouled. Idk if it's oil fouled or carbon fouled but my car does eat through oil. I need to run a compression test soon. How can i go about this though?

When I put my car into reverse the rpms drop and the car shakes like it's going to stall and same thing with putting it into drive. Even at idle my car shakes pretty bad but obviously because the cylinder 2 misfire is happening. Ive been putting NGKs in my car but last night decided to put BOSCH plugs into it because i have BOSCH coils as well.

The last test I need to do which I haven't done like I said is a compression test. My car does say I've been running lean (P0174 only) and I have done smoke test twice with no smoke coming out from anywhere.
 

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I need to run a compression test soon. How can i go about this though?
Search it up. Should be tons of them on Youtube.
I have a bad misfire on cylinder 2,
Find and remove the fuel pump fuse.
Pull the #2 coil and plug out, connect them all together and with glove hold the plug metal part touching on the engine metal, then check for spark when cranking the engine.
 

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Discussion Starter · #5 ·
Search it up. Should be tons of them on Youtube.

Find and remove the fuel pump fuse.
Pull the #2 coil and plug out, connect them all together and with glove hold the plug metal part touching on the engine metal, then check for spark when cranking the engine.
Compression test yea I know to search that up on youtube, but I didn't know about the spark check! Great advice I'll do that tomorrow, I also put a remanufactured fuel injector on that cylinder so possibly that is going bad. Thank you Sapote!
 

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Discussion Starter · #6 ·
you need to do a compression check then go from there
Yessir! I just need to ask for them to do the compression test. Unfortunately the tech is on vacation now so I'll have to wait. And I'd rather somebody with experience do it than me do something wrong even though it looks easy. Thank you for the advice man I will post up a compression test after I get it done.
 

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Discussion Starter · #8 ·
How much oil are you using?
Quite a bit, was putting oil in almost every week, we ran a compression test on cylinder 2 and cylinder 5 (they just wanted to make sure the tool was reading right).

Cylinder 2 was at around 60
Cylinder 5 was at around 185

Didn't test the other cylinders but i don't think it matters too much anymore.
 

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Discussion Starter · #10 ·
Turn the crank to have #2 TDC compression, then do a leak down test and listen to the leaking air through the removed oil filler cap, or the intake, or the exhaust. This will tell which valves are bent/burned or the piston/rings issue.
Okay I will get to doing that and update asap. Thank you for the advice so far.
 

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Discussion Starter · #12 ·
As much oil is on the plug, oil is getting in there from somewhere, rings or valve guides. With 60 psi compression, I’d say it’s rings
Yea I'd say so too, practically replaced everything that could leak oil except the dipstick tube o-ring, and oil pan gasket, so once everything else sealed up and created more pressure I believe my car took a shit (excuse my french), and now I'm at where I am with it. I would still get low on oil not even a week after putting oil in. I decided to put 5W-40 for the viscosity and even then I burned it after 2 weeks from my oil change. I'll still run that little test just to be sure. What would happen (while running the test) if it's both the piston rings and a burnt valve?
 

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Discussion Starter · #13 ·
Turn the crank to have #2 TDC compression, then do a leak down test and listen to the leaking air through the removed oil filler cap, or the intake, or the exhaust. This will tell which valves are bent/burned or the piston/rings issue.
Forgot to mention, we did do a wet compression test (afterwards) on cylinder 2 and poured less than a cap-full of oil down the cylinder and after cranking the compression went from about 60psi to 80psi. Another thing that leads me to believe I have bad piston rings.
 
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