e30 power loss and engine knock

enzo90

enzo90

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i was driving to work and while i was accelerating i suddenly lost almost all my power and my engine started knocking real bad

i immediately pulled over and shut off the car and had it towed to my house by my dad

i think i may have broken a rocker or something

anybody got any other thoughts on what might have caused it?

ill go ahead and pull off the valve cover and see if im right later today and give you an update
 
C

cliff

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yeah..sounds like something in the valve train....I would certainly pull the valve cover and look...yikes!!! good luck, keep us posted...cliff

and, hopefully, it isn't the dreaded e30 cylinder head bolt shear that is very common...happened to me but was lucky enough to have it lodge in a remote corner of the cylinder head...i shudder to think that if, god forbid, this bolt top got into the valve springs or otherwise....pure luck in my case.....good luck again....cliff

but you're right...quickest way is to pull the valve cover and look....it'll be clear really soon what's up....cliff

my guess is that a cylinder head bolt snapped and lodged in valve spring and caused the cam to partially lock due to the valve spring being frozen and shut the motronics down cause he's getting bad feedback....that's worst case though...very worst case....looking is seeing however...best luck on this...but an engine shutting down and making a racket can never be good...let us know...these are the kinds of issues i personally thrive upon....peace cliff
 
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enzo90

enzo90

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im hoping it wasnt the head bolts becuase i replaced them and installed a refurbished head 5,500 miles ago.

i still havent been able to check it out because of a sudden rain storm here but i'll get to it tomorrow for sure
 
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cliff

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and it may be somethng much more passive as well...only one way to tell...best luck on this....cliff



QUOTE=enzo90;204189]im hoping it wasnt the head bolts becuase i replaced them and installed a refurbished head 5,500 miles ago.

i still havent been able to check it out because of a sudden rain storm here but i'll get to it tomorrow for sure[/QUOTE]
 
C

cliff

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actually, the most obvious is that you snapped the timing belt...not good...but I would think that the engine would totally shut down then...not just lose power gradually..although it would make alot of noise either way
 
Doughnut

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Woah, Cliff is in rapid fire again!

A knock could be a variety of things, best place to start is by removing the dipstick and checking the oil then then remove your spark plugs and turn the motor over by hand to "feel" if it's crunchy, then move on to valve cover removal.

Yup, good luck!
 
enzo90

enzo90

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cliff said:
actually, the most obvious is that you snapped the timing belt...not good...but I would think that the engine would totally shut down then...not just lose power gradually..although it would make alot of noise either way
Click to expand...
id like to hope that it isn't the timing belt seeing as that too was replaced just 5,500 miles ago in late December
 
enzo90

enzo90

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well i checked the timing belt and it was good

then i pulled the valve cover and all the head bolts are there, same with all the rockers

i then turned the engine over with no plugs and the cover off and the knocking is still there in cylinder 5 or 6

any more ideas

my thinks i broke off a valve and its bouncing around inside one of the cylinders, does that sound possible
 
C

cliff

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if a valve had broken off you wouldn't be able to turn the engine

thats sounds possible but not probable....no...i don't see that


enzo90 said:
well i checked the timing belt and it was good

then i pulled the valve cover and all the head bolts are there, same with all the rockers

i then turned the engine over with no plugs and the cover off and the knocking is still there in cylinder 5 or 6

any more ideas

my thinks i broke off a valve and its bouncing around inside one of the cylinders, does that sound possible
Click to expand...
 
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enzo90

enzo90

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cliff said:
if a valve had broken off you wouldn't be able to turn the engine
Click to expand...
well it turns out that i did infact break off the intake valve on cylinder 6.

the valve stem snapped off about 3mm down from the top

so it somehow still kept opening and closing

but just make a whole lot of noise

so i guess its back off with the head and ill work on getting that fixed
 
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cliff

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wow...that's too bad...sorry to hear that. but I have never ever heard of a valve snapping or bending of its own volition. something else always causes that...even on indycar engines at least a broken valve spring...never on passenger cars....gotta be something behind that....good luck....cliff
 
enzo90

enzo90

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cliff said:
wow...that's too bad...sorry to hear that. but I have never ever heard of a valve snapping or bending of its own volition. something else always causes that...even on indycar engines at least a broken valve spring...never on passenger cars....gotta be something behind that....good luck....cliff
Click to expand...
yeah my car has a habit of breaking stuff that people have never heard of breaking before

like my shift linkage that broke a few months ago
 
enzo90

enzo90

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update:

the machine shop tells me that I've got a cracked head [V]

but some good news I've found someone that blew the head gasket in an s50 and are selling it for the price that they would get for a core charge ($500)

what i want to know is if it'll bolt up to my stock transmission

anyone know?
 
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cliff

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darn...a cracked head....what do you do about that? other than replacing the head....that's gotta hurt.....what model again?

actually, with a cracked cylinder head and holes punched into piston crowns sounds like the engine is trashed....no sense in trying to salvage that....could be more than the entire automobile is worth....in times of stress the devil eats flies...cliff
 
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enzo90

enzo90

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yeah when i bought the car it had a broken timing belt and came with a refurbished head (the one that just broke) so i'm just having the machinist make one good head from the two broken ones

but ill see if i just cant swap in an s50
 
echothreezero

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cliff - you see that little button at the bottom left of your reply??? It says EDIT in BOLD CAPITALS.

See it?

well when you click on it it lets you edit your reply to add anything you forgot to say the first time - that way you don't have to make 6 replies all in a row. in your case however, it should be relabelled "supererogatory dogma".

What did the BMw-driving buddhist say to cliff?......


Terribly sorry, but I ran over your Dogma with my Karma
 
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