Bent Valve

I have a 1999 Integra GSR which recently started having problems when
pushing the accelerator. It was happening in gear or in neutral. As long
as acceleration was gradual, no problem, but pushing the gas too fast
made the engine falter, as if not receiving enough gas or cylinders
misfiring. I did what I could at home, inspected spark plugs, wires,
distributor cap and rotor. Nothing unusual, so I drove it to Acura
service.

After a few days, they tell me they needed to change the distributor.
They said they turned the car on again and still noticed a problem. So
they do at least two more tests: check the compression on the cylinders
and a leak down test.

3 cylinders are ok (230 psi), number 2 only reads 190psi. 40 psi less
than normal. Their conclusion with these two tests is that I have a bent
valve.

I purchased the car with an extended acura warranty to 62,000 miles. I
bought it at 19,000 and it currently has 51,000. It also has a 100,000
mile powertrain warranty. But all these are useless because they told me
a bent valve is not covered by the warranty.

Final estimate to have bent valve repaired/replaced: $1200.

I have been on the phone with Acura Care (the warranty dept) various
times, but it is leading nowhere. The dealer refuses to open the engine
since he says he won't get paid. They told me I must have over-reved the
engine (for example dropping from 5th to 2nd) for a valve to get bent.
That hasn't happened. I love my car. I don't drive it that way. I put
10,000 miles a year on it. I try to take very good care of her. She even
has a name.

So, where do I go from here. I don't want spend $1200 on the assumption
that I have a bent valve without further inspection, which unfortunately
Acura is not willing to perform under warranty. I am taking it to a
mechanic/friend to repeat the tests Acura says they did and try to gather
more information (free of charge since it is a friend, it can't hurt).

From what I've read in the newsgroup, valves go in numbers and usually
due to some catastrophic event (i.e. timing belt breaking)... none of
which have occured in my car.

Is the Acura mechanic doing everything he can? Are those two tests enough
for him to determine I have a bent valve? Can I lose compression in a
cylinder due to other reasons (bad/dirty seals? injectors? etc)

Finally, if after getting a second opinion, or even a third evaluation, I
do have a bent valve no covered by warranty... do I go with Acura at
$1200? or is it something any decent mechanic (my friend) can handle?
(which he would do at very little cost to me) If it's not something that
can be tackled by anyone (i.e. I need a valve specialist?), can I at
least save on labor by having the engine disassembly done by my friend
and possibly save the valve 'job' for someone who specializes in that?

I was really looking forward to another 250,000 miles out of this car,
but I barely made it over 50,000. Any suggestions are welcome...

99 GSR

 

99 GSR,

If I only read the first paragraph of your (excellent) description, my
first guess would have been a jumped timing belt. Being 'out of time' by
a tooth or two would certainly cause your 'faltering acceleration'
problem. Winding it up with the belt (way) out of time could certainly
damage a valve, too.

I'd check the timing of the crankshaft to the cam(s) first, since it can
be done in about 10 minutes. You may also be able to see if the timing
belt is flapping in the breeze . . . . . Suggest you have a camcorder
along for evidence gathering, just in case you find something. :-(

'Curly'

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--

To REPLY: If there are a couple of underscores in my return address,
you must remove them to reply directly . . . . . . Thanks.

Regarding stage performances: When everyone else has finished playing,
you should not play any notes you have left over. -

 

If you have a bent valve you should notice a miss at idle. Locate the
missing cylinder.Raise the piston to top dead center.Remove the valve
springs and let the valves rest on top of the piston, rotate the valve stem
and if it is bent you will see the valve rise and fall as you turn the
valve. A good mechanic can do this. He may also put air pressure to the
cylinder and do a pressure test.etc. When he reinstalls or removes the
springs he may have to put air pressure to the cylinder to hold the valves
in place. Check all the cam lobes for wear. In some cases you can race or
goose the throttle and if the cam has a flat or worn lobe you will hear a
slight backfire noise at the throttle body if the air filter hose is
removed.

 

I want to add, put air press to the cylinder to remove the valve spring,
hold the valve as you remove the air press and then turn the valve when it
is on the piston, if good apply press and install spring. do each valve one
at a time. If you are not careful you could drop the valve into the cylinder
if the piston is not at tdc.. Once the piston is at top dead center I lock
the engine so it will not turn when I add air pressure to remove and install
springs. Let the mechanic do it if possible.

 

For starters the tech should be doing a pressurized leak down test and not a
compression test to check for cylinder leakage as compression tests dont
tend to tell you near enough. This will give you an amount of leakage such a
20%. It will also tell where the applied air is leaking out such as an
intake, exhaust or ring issue.

If you had a burnt valve I would expect your check engine light to be on
indicating a miss-fire condition (also telling you which cylinder). A scan
tool in the hands of a qualified tech will tell a lot more about what's
wrong with it when the problem occurs. In your case they just threw a
distributor at it..rookie move.

The dealer will require you to authorize tear-down of the engine due to the
fact that Honda/Acura Care will not agree to cover any repair until they
have the opportunity for an adjuster to come out and look at it
disassembled. If the shop is wrong about the valve or expresses their
opinion about over-revving...you will be out of luck.

My recommendation is to get a second opinion from a qualified Acura/Honda
tech as you likely will find that you have an ignition or fuel injection
issue.

PS. they might be right about the valve though..you never know. But that is
a big chunk of change.....

 

a bad head gasket will give you the same readings on the pressure as a
bad valve will

 

Thank you all very much for your suggestions and advice. They helped out when I
retrieved my car from Acura today, since I was able to push the mechanic for
answers. In the end though, he said there was nothing else he could do under
warranty. I was able to get him to admit that a bent valve was not the only
reason I might have a pressure leak, but he insisted none of the other reasons
were covered under warranty either. Whether it be carbon build-up on a piston
ring, a bent valve, a bad gasket, etc... under their warranty those all imply
problems due to car use/driving style etc, and not a factory defect. He went as
far as to say a valve could have bent downshifting only one gear (like 3rd to
2nd) as opposed to something like 5th to 2nd. That, I'm not so sure I believe,
but I'm not an expert.

So the current status is the car is operable. It 'misfires/falters' on hard
acceleration, but otherwise it drives. He said he could hear air leak out of
the cylinder if pressurized.

I am going to perform on my own the various tests you all suggested to find out
as much as I can before needing to remove the head of the engine. I feel
comfortable with the help of my mechanic/friend removing the head, but I will
probably need his supervision and I might have to leave it to him to
replace/clean the valves, springs, etc, if necessary. I also don't feel
extremely confortable assembling it and doing the timing, etc... another task
which I will probably need babysitting on. Is it possible that I might have
carbon build-up on a valve and it isn't seating properly (not sure about the
terminology there)? as opposed to carbon build-up on a piston ring? Is there
still any hope I might get out of those without replacement parts?

Either way, what I thought was going to be an expensive headache will hopefully
turn out to be a good learning experience. I guess I can thank Acura's we-
don't-cover-anything-in-your-engine-warranty for that, hehe...

Again, thanks for the advice, it was my first post on this group...

99 GSR

 

Carbon build-up on valves is possible.

You know, it couldn't hurt to run a couple bottles of Techron through
it.

 

--------------------------

gsr,
Another tip... Until you find out what's really wrong, check DAILY on
your oil (coolant contamination) and your coolant (oil foam) just in
case it is a head gasket leak.

'Curly'

---------------------------

 

Carbon build-up on valves is possible.

You know, it couldn't hurt to run a couple bottles of Techron through
it.