93 Shadow Stalling

I have a 93 Shadow ES 2.5 liter. It runs like a gem, but every other
week or so it will just stop running. It will either start to sputter on
the highway or die at a stop light. I replaced the map sensor, and I
thought that fixed it, but after a few weeks it started again.

I had it towed twice to my local mechanic. Of coursse it came of the tow
truck and started right up both times. He said it had an error code of
too lean or too little fuel. He checked everything and the only thing
that was even remotely odd was the waveform on the Hall Effect switch
(never heard of that). He replaced it. I picked it up and it died within
50 feet. The mechanic finally got it back to the shop after probably 20
starts/stops. Once back to the shop, it started up just fine (isn't that
something). So he keeps it for a week and drives it everyday with guages
hooked up to monitor fuel pressure. It ran perfect.

It does appear to idle low, at least the tach show about 250-500 RPM.
The engine doesn't "sound" like the idle is that low. It sounds fine.

The mechanic gave me a list of three things that he woul replace if it
was his car:
1. ASD Relay
2. Ignition Coil
3. Fuel Pump

I put on the Relay and Coil, and will attempt the fuel pump tomorrow
morning (looks kinda tricky if you follow all the "rules").


Any ideas?
Thanks so much!
Shane

 

When was the last time you changed the fuel filter it is underneath the
passage side floor boards. Before you change it do a fuel pressure test and
do one after you change the fuel filter. If the pressure was low with the
old filter and now is with in specifications it was the filter, if it is
still low after wards it is the fuel pump.
--
HarryS My 2¢
|I have a 93 Shadow ES 2.5 liter. It runs like a gem, but every other
| week or so it will just stop running. It will either start to sputter on
| the highway or die at a stop light. I replaced the map sensor, and I
| thought that fixed it, but after a few weeks it started again.
|
| I had it towed twice to my local mechanic. Of coursse it came of the tow
| truck and started right up both times. He said it had an error code of
| too lean or too little fuel. He checked everything and the only thing
| that was even remotely odd was the waveform on the Hall Effect switch
| (never heard of that). He replaced it. I picked it up and it died within
| 50 feet. The mechanic finally got it back to the shop after probably 20
| starts/stops. Once back to the shop, it started up just fine (isn't that
| something). So he keeps it for a week and drives it everyday with guages
| hooked up to monitor fuel pressure. It ran perfect.
|
| It does appear to idle low, at least the tach show about 250-500 RPM.
| The engine doesn't "sound" like the idle is that low. It sounds fine.
|
| The mechanic gave me a list of three things that he woul replace if it
| was his car:
| 1. ASD Relay
| 2. Ignition Coil
| 3. Fuel Pump
|
| I put on the Relay and Coil, and will attempt the fuel pump tomorrow
| morning (looks kinda tricky if you follow all the "rules").
|
|
| Any ideas?
| Thanks so much!
| Shane

 

The lean code could be a fuel pressure problem, but that would normally
cause a hesitation not just a shut down, It may slowly die to a slow too.
When was the last time you had the rotor button replaced on the distributor?
I have seen the button get a hole burnt thru it and ground out the secondary
ignition from the coil, this will cause the vehicle to shut down with out
warning,

Glenn Beasley
Chrysler Tech

 

Whats the rotor button look like?

 

Rule #1: Do not randomly replace parts in an attempt to solve the problem.
It usually doesn't work, and it usually costs a lot of money.

There is no fault code for "too little fuel". The only code that could
even semi-accurately be described this way is an O2 sensor fault code, but
here's the problem: Your mechanic's language is sufficiently garberated
that we don't know if the code he got was 51 (O2 sensor stuck at lean
position) or 52 (O2 sensor stuck at rich position). Here's why: If it's a
code 51, what he meant was "The O2 sensor is stuck lean". When that
happens, the engine runs too rich. A code 52 (O2
sensor stuck rich) produces the opposite condition: the engine runs too
lean, so he could've been talking about the *effect* of a code 52.

With either code, your O2 sensor is probably faulty. How long since it was
replaced?

Fairly common "stalls but then restarts" cause on these cars, but what
happened to that "too lean" code he got? The Hall Effect pickup will not
cause it; did he just decide not to figure out what was causing it?

This is the dashboard tach? Forget it; they're notoriously inaccurate.

See above.

Bull. See Rule #1. Your mechanic is guessing and needs replacement with a
competent diagnostician; this list is nothing but random parts replacing.
If the car has been at all neglected, then the list of places to start
looks like this:

-Fuel FILTER
-*Full* PCV system service (see http://tinyurl.com/yr2pg )

DS

 

The correct term in North America is "distributor rotor". It is under the
distributor cap. How long since the distributor cap, rotor, spark plugs
and spark plug wires were replaced?

 

Dan,

Well, the stalling is gone since I did the no-no an replaced the pump,
filter, and ASD Relay. While I was at it I did the distributor cao and
rotor, wires, and plug, PCV. Oh yea, found a real mushy motor mount on the
front, so I put a new one on.

Here's the deal now:
1. I does seem to be running at too low an idle in drive. In nuetral it
idles at 500RPM, put it in gear and we get about 0-100RPM plus a bit of
shaking, put it in reverse and we get even more shaking, same RPM. Turn on
the AC while in gear, forget about it! I feels like you put a quarter in a
bed at a cheap motel.

2. When coming to a stop at about 250RPM, the tach kicks ups to 500, and
then drops all the way to 0-100RPM. It does not stall, but shakes a bit

The shaking seemed to start after the mushy motor mount was replaced. Makes
sense, I guess.

Any ideas to get the idle smooth?

Thanks so much for your help my friend!
Shane

 

BTW - I bought an Oxygen Sensor yesterday, but have not put it on. It's
raining today.

Could the fuel pressure regulatore have anything to do with the idle
problem?

Also, the plugs looked white to me, not fouled out (I think that it what
that means).

Shane

 

Well, the problem might've been in there...somewhere. That's a really
expensive "shotgun" way to find the problem, though.

AIS motor is dirty or faulty, or its wiring is faulty,

Vehicle Speed Sensor could be making problems without setting a code 15.

Start with a complete go-through of the PCV system (not just the valve!)
and careful inspection of ALL the vacuum hoses in the area of the throttle
body and camshaft cover. They cook/crack/break with age. Also, install a
different PCV valve from the one you got. Info here:

http://tinyurl.com/6hkvt

Don't know which spark plugs you put in; NGK ZFR5N plugs help smoothness,
driveability and mileage on these engines. That is a spark plug used in
late-model 3.5 and 4.0 litre engines and many others. Autolite equivalent
is 985. The electrodes project farther into the combustion chamber,
picture here:

http://www.ngk.com/productImages/1/zfr5n.jpg

DS

 

Should I replace the AIS Motor and Vechicle Speed Sensor?

You have been VERY helpful. You are very knowledgeable about this stuff!!!



Shane

 

The VSS will tend to get lazy and dumb after 10 years. Replacing it is not
a bad idea IF it is not giving a proper signal. The AIS is expensive --
better to do proper diagnosis, cleaning, and inspection of the wires.

Parts replacement is a very expensive means of diagnosis...you'd be
happier and richer in the long run if you got the car to a competent
diagnostician.

DS

 

Daniel,

I was wondering was I was going to be referred to someone who knew what they
were doing, and your right, but:

1. I am the kind of person that desires knowledge. I own an IT company that
does several very high-end IT tasks, and I have never spent a day in school
for it (but ironically, require certification for my employees). This is my
fourth car (others are Dodge van, 2001 Durango, 2000 Mustang GT). So I want
to learn on this car.

2. A while back I got a DUI and I have a breathalyzer (blow into it before
the car will start) on the car, and most techs don't want to touch it. It's
a real pain. If it gets bypassed I could lose my license and I am too close
to completing the program to screw that up. The upside is I have been sober
for close to 3 years now. Finally!

I went through the entire PCV maintenance in the thread you sent me. Very
well written. I did find a broken line of the sensor inside the air cleaner
housing. I fixed that and replace the 90 degree elbow from the crankcase to
the PCV.

The car is running GREAT at speed, but the idle is still a bit rough. I
might just have to deal with it. Being a perfectionist it is hard to let it
go. The AIS motor makes sense, it appears the be on the front of the
throttle body, and the throttle body would need to come off to get to it.
The VSS looks real hard to get to.

If I could ask, how would one go about "testing" these parts for proper
signal. Does it require expensive tools or will a standard volt meter work?

Daniel, I really appreciate your tolerance and patience when dealing with
these questions. Thanks again.

Shane

 

I always seem to forget something:

Yesterday I did the key-on-off-on sequence and got the following codes:
12, 21, 51, and of course 55. I do not know if these are residual codes or
not. How does the computer reset? Is it after a period of time, or do you
disconnect the battery for a period of time (breathalyzer wont like that).

Thanks!
Shane

 

Keep it up.

OK, both of those fixes will help...

VSS is very easy to get to. Remove air cleaner assembly and you're staring
right down at it, on top of the RH extension of the transaxle housing,
held in by one bolt, with a 2-wire plug on it.

I only get snippy when faced with dumb/thoughtless questions. Haven't seen
any of those out of you.

DS

 

To clear the codes, you do need to disconnect power (either remove the
battery negative cable or pull apart the plastic main disconnect plug in
the positive cable) for a few minutes.

21 means your Oxygen sensor is still making problems.

51 also means your Oxygen sensor is still making problems.

Replace it! (don't use Bosch).

 

Geez, I replaced it yesterday with Bosch!!!!


Shane

 

Bosch O2 sensors fail early and often in Chrysler applications.

 

Im done with this thing. If it runs, it runs. If not, it get donated.

Thanks for the help!

Shane

 

See, this is the problem with your repair method. You spend lots of money,
time and effort replacing lots and lots of parts in the hope that
something you replace will fix the problem, it doesn't, and you decide the
car's a piece of junk.

Proper and systematic diagnosis is the way to go.

DS