Dodge Shadow Engine Quits

Hi,

I have a problem with my 94 3L Dodge Shadow, 98k miles.
Sometimes the engine just quits, i.e. it just goes out. It always
happens when I have been driving for a while, usually on a freeway, and
then exit and have to stop at a light or a stop sign. However, now it
seems that the problem occurs more frequently. When it happens, the rpm
just just drops dramatically until the engine dies. When I start it
again the rpm drops immediately again and the engine turns off again.
So what I have to do to keep it running is to accelerate (stay on the
gas) to keep the rpm at a higher level and then suddenly shift into D
or better L to get moving.
I noticed that when I manually shift fist into 3 and then into L every
time I have to stop while driving the problem does not occur, however
this is not really a good solution.

One other thing, I think that the rpm in idle is very low. It is at or
below 500rpm. Does anyone know what is normal for an autom
transmission?

A mechanic I asked about this, said that they would have to run engine
diagnostics and that they cannot solely adjust the idle rpm. However,
I'm worried that I'll spend 100 bucks and the problem doesn't occur.

It would be great if anyone had some kinda help for me with this
problem.

 

A few things:

1) You can check to see if the computer has stored any flash codes all by
yourself, at a cost of $0.00.

To check the computer codes:

With the engine off, switch the ignition key on-off-on-off-on,
leaving it "ON". Do not
go to "start", just "on" during this procedure.

Watch the "Check Engine" or "Power Loss" light. It will turn on, then go
off, then will begin to flash-out any trouble codes that have been stored.
For instance, if it flashes:

flash <pause> flash flash
<long pause>
flash flash flash <pause> flash flash flash flash flash
<long pause>
flash flash flash flash flash <pause> flash flash flash flash flash

Then you have a 12 (one flash followed by two) a 35 (three and five) and a
55 (five and five). 55 means "end of codes" or, if by itself, "No codes
stored. Check the codes and report what you find.


2) The 3-litre V6 tends to dirty-up the throttle body and AIS motor (IAC),
which causes stalling, low idle and other driveability quirks. If you
cannot remember the last time the throttle body was thoroughly serviced
(T-body removed from intake, AIS motor removed from T-body, both parts
thoroughly cleaned and reinstalled with new gaskets) you're probably
overdue.

3) The 3-litre V6 is also very sensitive to the condition of the crankcase
ventillation system. Not just the PCV valve, but the crankcase inlet air
filters (both of them) and the hoses and fittings. Any broken, cracked or
clogged parts can cause improper idle and stalling. It's very common for
this system to be ignored, or at best just the PCV valve replaced. Here
again, if you cannot remember the last time the entire crankcase
ventillation system was inspected and serviced, you're probably overdue.

4) Of course, you cannot expect the car to run properly unless the
wear parts (spark plugs, plug wires, air and fuel filters, distributor cap
and rotor) are in good condition, and the ignition timing is set
correctly!

DS

 

Go get yourself a fresh throttle body mounting gasket ($6 or $7 from the
dealer) a can of Gumout or similar aerosol carburetor cleaner,
some Q-tips and rags and...

o disconnect battery negative
o remove the cables from the throttle body (accelerator and cruise)
o disconnect the two plugs -- one for the IAC and one for the TPS
o remove the throttle body from the intake by loosening the two 13mm
nuts
o remove the TPS sensor and set it aside (i.e. don't get Gumout on it)
o remove the IAC motor
o clean the inside of the throttle body until all black gunk is removed
from the throttle plate and IAC passage (use Q-tips on the air passage)
o clean the pintle on the IAC motor
o clean up any remaining gasket material on the intake/throttle body
mounting surfaces
o reassemble the IAC and TPS to the throttle body
o reinstall throttle body, mounting nuts, electrical connections and
throttle cables
o reconnect battery negative and test drive.

I cleaned mine up while holding it over an old oil drain pain, and used
*plenty* of carburetor cleaner. Do this in a well-ventilated area.

BTW: IAC = AIS = solenoid that controls the amount of air the engine
gets when the throttle plate is closed (at idle)
TPS = throttle position sensor = tells the engine management computer
how far the throttle plate is open.

This will cure the problem 8 or 9 times out of 10 on a 3L that's
stalling in the manner you describe.

--Geoff

 

Not a solenoid. It's a stepper motor.

 

Absolutely correct. My bad.
--Geoff

 

My moms got my little 94 3.0 Duster now but it would once in a blue
moon do exactly this. Didn't have any other problem with idle speed or
drivability at all the rest of the time - it would just die while
coasting thru a parking lot or to a stop light, then maybe take a
couple of cranks to start it up again and then would be good to go till
it did it the next time (about every 10K miles I'd guess). So I never
really looked into it further, not a big deal. Other than this the car
has been a total gem, never been back to the dealer or had an actual
repair other than normal maintenance after 65K and still looks like a
brand new car. She LOVES that Duster! Perhaps I should clean the
throttle body though....Frenchy

 

If your mom's '94 has the 5-speed manual or 3-speed automatic, another
common cause of "stalls when coming to a stop" is a faulty vehicle
speed/distance sensor. They're easy to change.

DS

 

Nope, got the 4A...

 

Beejay, clean out the throttle body, make sure you get all the build up off
the throttle blade and the inside of the throttle body Bore, with the engine
off just get some throttle body cleaner, gum cutter or something similar
and using a tooth brush clean it good, that will probably take care of your
problem and very easy to do.
Glenn Beasley
Chrysler tech

 

I have a '93 Shadow and two times this week it died on the Interstate
(ironically the same spot). It had been real cold here lately. The
first time I checked the map sensor, and in the line was ice. I cleaned
it up, and back on the road. The second time there were no ice
crystals, so I walked to Pepboys and bought a map sensor for $35.00.
Walked back to stranded car, installed the sensor. It fired up
immediately and has had no problems since.
I had the EXACT same symptoms as you decribed. Hope that helps.

Shane