Hosing off engine bay

How much mileage is on your car? If you're having problems like that, it
may well be that your wires and/or plugs are due for replacement (if
your car has a distributor, odds are that the cap is cracked). Check to
make sure that the plugs wells are not filled with water. When the
engine is running, listen for electrical crackling sounds under the hood
and look at the wires, plugs and coil packs (or distributor) for arcing.

What you are experiencing is not normal and it indicates an electrical
problem that needs to be addressed.

 

The car is a 2001 Accent with 123,000km but the plugs and wires were
replaced 2 years ago. I remove the leads at the coil side and they
seem dry, the engine side is under a cover.

The car is running just slightly better after drying all night. It
idles rough and the engine knocks at low rpm when I am on the road.
The exhaust dropped black carbon on my floor this morning. The plastic
piece (spoiler thing) in front of the cat? has melted but I cannot be
sure that this is recent. I will get it in to service next week.

Funny thing is I had no problems and just wanted to clean my car.

 

It sounds like you ingested some water into the engine. This is pretty
hard to do, but if the engine is making a mechanical knocking sound, it
is possible that you ingested enough water to get a hydraulic lock in a
cylinder when you first started it and bent a rod, cracked a piston, or
cracked or chipped a valve. Again, this is really hard to do with
modern intake systems, but it isn't impossible if you get water hard
enough into the intake system. Good luck at the garage.

There's an old saying about not fixing things that aren't broken.
Washing an engine certainly can be done without harm, but done wrong
there is the potential for great harm to the engine. It is just like
folks that speed into water a foot deep and wonder why they kill their
engine.


Matt

 

I doubt that the engine took on water because I did not use that much
to clean. I was careful to clean around the engine bay only and not
the engine. If anything I should have left it to dry instead of
driving it right away with the CEL blinking. Live and learn.

 

The weird part is that you say the engine is making a knocking sound.
That isn't typical of an electrical problem. And the only way I know of
for water to cause an engine to make a knocking sound is to get a
hydraulic lock in a cylinder and bend or crack some metal. Maybe others
here can think of another way that a little water could cause a knocking
sound, but I can't.

The rough idle could easily be a wet ignition component or sensor, but
the knocking sound is of much more concern.

Let us know what you find at the garage next week.

Matt

 

Maybe I am not describing the problem correctly. It is definitely a
rough idle but no "knock" sound when it is parked. Only when I am
driving at low rpm, it feels like the engine is near stalled then I
hear the "knock", may not be the engine but somewhere else. I play
with the throttle to keep the car moving.

The car is drivable but I do not want anymore problems.
Wonder if I should get it towed.

 

If the engine is nearly stalling all of the time, then maybe the
knocking isn't a mechanical failure. No way to tell without hearing it
first-hand. If you are sure you didn't get a lot of water into the
intake, then I don't see how you could have done any serious damage to
your engine.

It doesn't seem like driving it should cause any further damage,
although if it is misfiring badly it is possible to dump enough raw gas
into the exhaust system to burn up the catalytic converter and that is a
pretty expensive repair.


Matt

 

I afraid that is what has happened. I have decided not to replace the
catalytic converter if it is needed. Is it an option to fix just the
misfiring and continue driving the car with a damaged catalytic
converter?

Thanks for your time.

 

Accent, you can always try a test pipe on the cat ( snicker ), I know in
the older days we used to have a pipe made to replace the cat.... Im not so
sure its a good idea these days the way technology has changed but if you
can get a muffler shop to make you one JUST TO TEST and see if the cat is
bad it may be worth the $25 - $30 to try it.

Tunez

 

It depends on the damage. Burning raw gas often melts part of the
converter substrate and this will increase back pressure, sometimes
dramatically. Your car will NOT run well if that is the case. Also,
and I'm not familiar with the Accent to be sure, many cars now have both
an upstream and downstream oxygen sensor. If the catcon isn't working
properly, this will light the check engine light. In many states now
this will prevent your car from passing the annual inspection.

And that is to say nothing of the pollution you are spewing into the
environment.

It will be better to get it fixed correctly, even if that does require a
new catcon.


Matt

 

re: drying engine

if something gets tooo damp and doesn't start or run up to snuff, then
what would WD-40 hurt (which parts shouldn't be sprayed with wd-40)?

it's considered more of a "dryer" than lubricant from what i've
previously ascertained in these n.g.s, tho i sort of use it for
everything along with duct tape

 

Based on the fact that he's getting sooty exhaust and it appears that
the catalytic converter has overheated, I'd say that's definitely NOT
the case. It would be almost impossible to do, anyway. It's far more
likely that he just has a bad misfire due to an electrical problem. That
would explain both the overheated cat and the soot.

 

The knocking is likely caused by cross-firing cylinders.

 

What brand of wires and plugs were installed? Some aftermarket wires are
junk right out of the box.

Remove the cover from the engine and check underneath. You may find the
source of the electrical problems there.

 

I overheated my cat converter just the way you apparently did. Aside from
smoke, flame, and consternation, it didn't hurt anything. The cat lasted
another 3 or 4 years until I sold the car.

The secret to drying the engine out is to run the engine al little, and dry
it a lot. Keep the hood open and in full sun and wind if you can.

 

The car has been maintained at a Hyundai dealership. I assume that
they will use OEM parts but I really have no clue.

This time the car went to an independent garage. The scan and scope
test indicates the a complete tune up is needed including wires and
plugs. Any damage to the catco will have to be assessed after the
tuneup.

 

I'm sure that's the case.

Did you check it out yourself, first?

Make sure the garage saves the old parts. If the problem turns out to be
something else, the old parts will make good spares. This is also work
you should consider doing yourself, as it's easy and at least you know
what was done and how.

There's really nothing more to a "tune-up" unless you want to replace
the air filter, too.

Hopefully, there won't be any residual problems.

 

I did not bother checking it out first and decided to leave it to the
professionals. The tuneup must be more to it because it comes with a
high cost. The OEM air filter is brand new. I will leave the old parts
to the garage.

What other items should be in a complete $300 tune up with $100 scope
and scan test?

1. wires and plugs
2. oil and filter (2000km earlier than scheduled)
3. valve timing

 

That may have been a mistake.

Why? You paid for them, didn't you? If they're relatively new, they'll
make good spares.

There is no way you should be spending $300 on a tune up. Wires and
plugs should be under $100. If you don't need an oil change for another
2K miles, don't do it. There is no adjustment for valve timing. $100 for
"scope and scan" is ridiculous, too. It sounds like you're getting
screwed. Just because someone gets paid for working on cars, it doesn't
make them true "professionals".

 

I have a feeling that I am not getting the best value for my money
because the car was running fine before my ordeal. I will see what is
on the itemized bill when I pick up my car. Would be nice if I also
got a coolant flush, transmission flush and new fuel filter.

It is too bad that I did not follow your good advice and check the
plugs and wires. Next time the car is misfiring, it will be the first
things to be checked.