Misfires and flashing CEL

[ecp]

Originally Posted by Stl-986

did you have plastic bits in the oil pan?

Leak down test would have helped before as that will show a valve issue usually.

snap some pictures of the head, maybe it will be obvious if it's a spring.

You did lock the cams right? Both of them?

Yes the dealership did a leak down test and borescope. I’ll try and attach photos if i can figure it out, i have an iphone. and yes i have both cams locked

There’s always been some plastic bits in the oil. I’m pretty sure it’s the chain guides. i replaced the IMS last july

[ecp]

i pulled the exhaust cam, a definitive broken valve spring broken on cylinder two, need to pull the intake cam to look at the intake springs on cylinder two or one.

Do you guys think i need to pull the head? i’d definitely like to avoid that if i could. I’ll probably end up replacing all the valve springs if two simultaneously broke to be safe.

also any tips on reassembling? i marked the chain and sprocket with a marker and have the lock tool from my Ims kit. it’s a variocam 3 chain motor

[blue62]

Originally Posted by ecp

i pulled the exhaust cam, a definitive broken valve spring broken on cylinder two, need to pull the intake cam to look at the intake springs on cylinder two or one.

Do you guys think i need to pull the head? i’d definitely like to avoid that if i could. I’ll probably end up replacing all the valve springs if two simultaneously broke to be safe.

also any tips on reassembling? i marked the chain and sprocket with a marker and have the lock tool from my Ims kit. it’s a variocam 3 chain motor

These are interference engines.

If you have broken valve springs then there is a very good chance that the pistons have contacted those valves.
So the valve stems on those valves could be bent or there could be damage to the valve guides, and or damage to the valve seats.
Or other damage.

The only way you are going to know if there is damage is to remove the head and have it checked out by a good machine shop.

You may have dodged a bullet and can save that engine.
Pull the head and have a automotive machine shop examine the head and check the specs.
That is the prudent thing to do.
Anything else would be foolish in my opinion.

[ecp]

Originally Posted by blue62

These are interference engines.

If you have broken valve springs then there is a very good chance that the piston has contacted those valves.
So the valve stems on those valves could be bent or there could be damage to the valve guides, and or damage to the valve seats.

The only way you are going to know if there is damage is to remove the head and have it checked out by a good machine shop.

You may have dodged a bullet and can save that engine.
Pull the head and have a automotive machine shop examine the head and check specs.
That is the prudent thing to do.

I did another borescope (at home). no contact with the piston, no seat damage. i was able to wiggle it around just enough to get a good look at the seat and it looked good.

Honestly at 124k miles, i’d rather start saving for a new or upgraded motor. I thought about pulling the head, but the borescope answered questions i had. The spring broke in such a way that it wouldn’t return fully, but it wouldn’t go in far enough to hit anything either. No damage to any piston.

I think that cylinder one was “dead” because the ecu went into some kind of mode or just couldn’t compensate for the one cylinder with zero compression.

I’m trying to decide now if i should replace all 24 springs, just the springs on bank one, or just the one spring. they look okay, but if one broke, others might soon follow. replacing all the springs and getting it back on the road is worth it to me. Any thoughts on that or good while you’re in there’s are welcome

I do love this car so spending the money for a new engine down the road doesn’t bother me. i just don’t have that kind of cash right now

[blue62]

Originally Posted by ecp

I did another borescope (at home). no contact with the piston, no seat damage. i was able to wiggle it around just enough to get a good look at the seat and it looked good.

Honestly at 124k miles, i’d rather start saving for a new or upgraded motor. I thought about pulling the head, but the borescope answered questions i had. The spring broke in such a way that it wouldn’t return fully, but it wouldn’t go in far enough to hit anything either. No damage to any piston.

I think that cylinder one was “dead” because the ecu went into some kind of mode or just couldn’t compensate for the one cylinder with zero compression.

I’m trying to decide now if i should replace all 24 springs, just the springs on bank one, or just the one spring. they look okay, but if one broke, others might soon follow. replacing all the springs and getting it back on the road is worth it to me. Any thoughts on that or good while you’re in there’s are welcome

I do love this car so spending the money for a new engine down the road doesn’t bother me. i just don’t have that kind of cash right now

You can do what ever you like it's your car.
I gave you my opinion and I stand by it.
Keep us posted.

[ecp]

Originally Posted by blue62

You can do what ever you like it's your car.
I gave you my opinion and I stand by it.
Keep us posted.

I do appreciate your opinion. if i had the cash and lots of time i’d definitely take that route. unfortunately i only have time to work on it during the weekends, if it’s not raining of course