Dodge Stealth engine shudders when under a load.

My Stealth has been in the garage for about 4 years without having been
driven much. Now when you drive it you get a shudder. I put some Lucas fuel
cleaner in it and I'm ordering a gas filter for it. Anyone have any other
ideas as to what it could be? Tank is full so I'll have to drive it out to
put new gas in. Only seems to shudder when under a load, like when you get
it up to 3000 rpm in 3rd. Half expecting a backfire but have yet to get one.

KY

 

Is this a manual transmission? Shuddering is often caused by automatics,
and you didn't say whether you had the girly model Stealth.

 

No I have a very manly 5 speed. a automatic is a waste in a sports car IMHO.

KY

 

So it doesn't do it at low rpms? If it was the engine, I'd expect it to be
worse at 1500 rpm than it is at 3000, if you know what I mean.

 

its almost like it isnt getting gas or a dead spark plug. Might have to
check the plug wires. it only has 58k miles on it. I just dug a mouse nest
out from under the intake manifold, I guess that is what the cast aluminum
part is between the valve covers. I haven't worked on engines since I sold
my '71 ford Torino GT so all the stuff under that hood is like it came from
mars or something. LOL

KY

 

To which I would reply that anything built by Mitsubishi is a waste of
the term "sports car," but I digress

But seriously, shuddering under load with a manual trans pretty much has
to be a misfire or a broken motor mount- have you checked for excessive
engine motion? Have you checked the plugs and plug wires? It could also
be a clogged injector causing that particular cylinder to lean-out under
load.

My advice would be to drain the gas tank and get fresh fuel in there,
check the plugs and wires, and then see what happens. I don't know how
to read the error codes on Mitsubishi-built faux-Mopars, but certainly a
code reader could do it if there's not a "cheat" like there is on
Chrysler-built cars. Many parts stores offer free code-reading. That
might provide a better starting point than our SWAGging.

 

I think you just answered your own question there. Mice love wire
insulation and most other types of insulation too. Why carry the
stuff to build a nest all the way from the yard when you can just chew
up some of these nice yummy wires! You will probably find that they
have nibbled at the spark plug wires and a few other wires as well but
the plug wires are where I would put my money as being the culprit
here.

Steve B.

 

thanks. I appreciate it.

there hasn't been a check engine light go off though.

KY

 

I had a '93 Stealth and really enjoyed it. I decided to sell mine when
we moved to a different state (pesky IRS).

Unfortunately I don't think your problem is repairable. Your best bet is
to sell it to me.

--
Gyz

07 Saturn Sky
98 Dodge Status ES
94 Mitsubishi Eclipse GST

 

Dirty plugs, dirty injectors, bad wires, dirty throttle body, plugged air
filer, defective AIS, bad EGR?

Most of that is pretty simple stuff to replace. I'd burn through a couple
tanks of fresh premium gasoline before making any changes.

Bob

 

LOL I love the car, really. But I am getting to darned old to get in and out
of it without pain. LOL bought it when I was in my early 30's but am almost
49 now. I'm waiting a few more years to sell. You see very few of these on
the road any more, so I think they may get to a classic statis some day.

KY

 

Ok just changed the air filter and that wasn't it. Taking it to get new
plugs and plug wires tomorrow. Seems like after 10 years or so the plug
wires tend to go bad in my experience. I put 2 bottles of Lucas fuel
treatment in the tank for the injectors and that hasn't helped. I know what
the EGR is I had one on my '71 Torino GT growing up and had to replace that
myself. Haven't fooled with an engine since those days. What the heck is a
AIS? LOL


Was going to drive it to work this morning but it was much worse than it was
yesterday. Don't know if it was the damp morning air or what, got half way
to work and turned around and came back to get the truck. Darn truck is a
gas guzzler.

KY

 

My 1991 is the first model year that was made. Just turned 137K miles and
so far, other than normal maintenance, several sets of tires, a window
regulator, and an alternator at about 80K miles, everything is still working
fine. It has some dings here and there and scratches in the windshield, but
otherwise has no rust and looks like new. Not bad since the car is now 17
years old! By the way, I'm the same age and getting in and out is not as
much fun, but once behind the wheel you forget the trouble it took to get
there.

Bob

 

Plugs are expensive on this vehicle so be prepared to take a home equity
loan!

If I recall last tune up I did the NGK platinum (60K mile) plugs cost me $11
or $12 each over the Internet. And to get to the back three plugs/wires
requires removal of the intake manifold so is not a "simple" tune up. But,
the most difficult maintenance item has to be the timing belt and water pump
.... these are scheduled to be done every 60K miles too. Good luck

Bob

 

Did the timing belt a while back. that ran me $300. LOL $1200 that trip. had
some other stuff that was bad. May sell it after I get it running right. LOL

 

LOL yep and my name is Bob too. LOL

Mine is the pearl white that Dodge did that first year. Actually has crushed
pearl in the paint. And it still looks like new, 58k miles and a couple
chips in the paint about the size of a pin head but no dings. I do need to
replace the window tint on the drivers side and there is a small cut in the
drivers seat that my gun caused. But after I washed it this weekend I was
amazed at how new it still looked.

KY

 

My '91 is pearl white as well. It burns some oil and the upper valve train
sounds terrible till it gets warmed up, but it still runs pretty well. I am
considering rebuilding the engine and transmission, replacing the shocks and
the scratched windshield in a couple years down the road.

By the way, my red leather interior looks great except for the small cut in
my drivers seat. This car originally came from CA via NV so lived most of
its life in the dry desert. I only drive it in the summer and then put it
into storage. That is why it is still in good shape even though I live in
the rust belt.

Bob

 

If the problem is strictly on the secondary (high voltage) side of the
coils (ie a bad plug or wire) a pre- OBDII engine controller won't
always detect it. Also, you CAN have internally set error codes that
won't always trip a CEL, especially on pre- OBDII cars. And there are
intermittent faults that might set a CEL, then it will go off on the
next engine start but the code will be held in memory. Its always a good
idea to start by checking codes. For the most part I'm a fan of older
cars, but one thing I will credit newer computer-controlled cars with:
they can tell you where it hurts a lot better than a set of breaker
points and a carburetor!

 

"Oil consumption" and "Mitsubishi" go hand in hand. But those v6s will
keep running and running and running forever, even with the oil
consumption. Provided you don't let 'em run dry, anyway.


Gotta confess- I LOVED the look of the Stealth when it came out (still
do, actually) but I developed such a strong allergy to Mitsubishi
powertrains that it wasn't even close to an option for me. Now if only a
Chrysler 3.5 HO would fit in the hole..... But alas, its a
different bellhousing pattern and it only gets worse when you start
considering width, accessory placement, manifolding, etc. :-/

 

would be nice to have a interface and software to hook up a laptop to the
car and read those codes.

KY