1993 SL bucks... suggestions?

You can get the codes read for free at autozone and pick up any parts you
need at about as cheap as you'll find anywhere. One trip, possible
solution.

As to ECMs going bad...
They don't go bad on their own very often; that much is true. However,
other factors can lead to them failing due to stress' inflicted by poorly
done maintenance, broken casings, other bad parts, or when they do have
problems it usually happens with increased heat that triggers expansion.
The expansion causes defects in materials or poor assembly to come apart and
loose conductivity. This happens even in military grade ICs and components,
and as an engineer and technician I've seen plenty of these 'rare'
ocurrences.

I'm not telling you to go straight to swapping parts, I'm telling you to go
to an 'experienced' mechanic/technician with Saturns to have it checked on,
or read the codes at Autozone for free and take a stab at fixin' the
situation yourself. That is all! The ECM/coil pack experience I had was
just an antecdote, harping on a few Mr. Goodwrench guys at Kenny Kent in
Evansville, IN...
PS... I know some good mechanics there as well, but Larry, Darrell, and
Darrell there soured me a bit.

Ok gang... Here's the deal:

Went to the mechanic (he specializes in GM and I trust him
wholeheartedly)... although he's not a specific Saturn mechanic. We
(and by WE I mean HE) read the codes and it popped up with a 53 and a
45. He wasn't sure if they had not been cleared, or if they had been
caused, by a previous dealership visit. So, he cleared 'em anyway. We
changed the O2 sensor. The jerking and "misfiring" still happened. We
(HE) checked the codes again, and nothing popped up on the computer.

I'm going to drive it for a few more days to see if anything will pop up
on the scan tool. Any ideas on what the code 53 is? He thought it was
the computer and the 45 was the O2 sensor.

I searched on code 53 via Deja and someone, a while ago, posted it as
being ECM related on a 1991 or 1992. As this is a 1993, I didn't know
if that still applied.

Thanks again everyone!

Marty (remove NOSPAM to reply privately)

hoosier_drifter wrote:
> You can get the codes read for free at autozone and pick up any parts you
> need at about as cheap as you'll find anywhere. One trip, possible
> solution.
>
> As to ECMs going bad...
> They don't go bad on their own very often; that much is true. However,
> other factors can lead to them failing due to stress' inflicted by poorly
> done maintenance, broken casings, other bad parts, or when they do have
> problems it usually happens with increased heat that triggers expansion.
> The expansion causes defects in materials or poor assembly to come apart and
> loose conductivity. This happens even in military grade ICs and components,
> and as an engineer and technician I've seen plenty of these 'rare'
> ocurrences.
>
> I'm not telling you to go straight to swapping parts, I'm telling you to go
> to an 'experienced' mechanic/technician with Saturns to have it checked on,
> or read the codes at Autozone for free and take a stab at fixin' the
> situation yourself. That is all! The ECM/coil pack experience I had was
> just an antecdote, harping on a few Mr. Goodwrench guys at Kenny Kent in
> Evansville, IN...
> PS... I know some good mechanics there as well, but Larry, Darrell, and
> Darrell there soured me a bit.
>
>

No personal experience with it, but - Here is what my OEM 91-94 Electronic
Engine Controls manual says about code 53.

Code 53 will set if the PCM is unable to eliminate engine knock by retarding
timing. (i.e. the engine noise is most likely not due to spark knock) It
does not indicate a faulty knock sensor. Most likely causes Valve lifter.
Belt Tensioner. Loose Bracket. Low Octane Fuel in high Ambient temps while
pulling loads. Piston/Cylinder scuff.

Once the knock condition is corrected, the code 53 should be erased by
disconnecting power to the PCM- it does eventually learn back the '0'
condition, but is a very slow process. (paraphrased)

1991, 1993 and 1994 the PMC also relies on coolant temp in order to select
the correct spark retard value table (they specifically leave out the 1992
in this statement).

Maybe some of this can set you on the right track to finding your problem.

"K. Daver" > wrote in message
. ..
> Ok gang... Here's the deal:
>
> Went to the mechanic (he specializes in GM and I trust him
> wholeheartedly)... although he's not a specific Saturn mechanic. We (and
> by WE I mean HE) read the codes and it popped up with a 53 and a 45. He
> wasn't sure if they had not been cleared, or if they had been caused, by a
> previous dealership visit. So, he cleared 'em anyway. We changed the O2
> sensor. The jerking and "misfiring" still happened. We (HE) checked the
> codes again, and nothing popped up on the computer.
>
> I'm going to drive it for a few more days to see if anything will pop up
> on the scan tool. Any ideas on what the code 53 is? He thought it was
> the computer and the 45 was the O2 sensor.
>
> I searched on code 53 via Deja and someone, a while ago, posted it as
> being ECM related on a 1991 or 1992. As this is a 1993, I didn't know if
> that still applied.
>
> Thanks again everyone!
>
> Marty (remove NOSPAM to reply privately)
>
> hoosier_drifter wrote:
>> You can get the codes read for free at autozone and pick up any parts you
>> need at about as cheap as you'll find anywhere. One trip, possible
>> solution.
>>
>> As to ECMs going bad...
>> They don't go bad on their own very often; that much is true. However,
>> other factors can lead to them failing due to stress' inflicted by poorly
>> done maintenance, broken casings, other bad parts, or when they do have
>> problems it usually happens with increased heat that triggers expansion.
>> The expansion causes defects in materials or poor assembly to come apart
>> and
>> loose conductivity. This happens even in military grade ICs and
>> components,
>> and as an engineer and technician I've seen plenty of these 'rare'
>> ocurrences.
>>
>> I'm not telling you to go straight to swapping parts, I'm telling you to
>> go
>> to an 'experienced' mechanic/technician with Saturns to have it checked
>> on,
>> or read the codes at Autozone for free and take a stab at fixin' the
>> situation yourself. That is all! The ECM/coil pack experience I had was
>> just an antecdote, harping on a few Mr. Goodwrench guys at Kenny Kent in
>> Evansville, IN...
>> PS... I know some good mechanics there as well, but Larry, Darrell, and
>> Darrell there soured me a bit.
>>

Mike,

AWESOME. Thank you very much for posting that! I'll forward that to my
mechanic and post the results.

Again, MANY MANY thanks..

Marty

Mike wrote:
> No personal experience with it, but - Here is what my OEM 91-94 Electronic
> Engine Controls manual says about code 53.
>
> Code 53 will set if the PCM is unable to eliminate engine knock by retarding
> timing. (i.e. the engine noise is most likely not due to spark knock) It
> does not indicate a faulty knock sensor. Most likely causes Valve lifter.
> Belt Tensioner. Loose Bracket. Low Octane Fuel in high Ambient temps while
> pulling loads. Piston/Cylinder scuff.
>
> Once the knock condition is corrected, the code 53 should be erased by
> disconnecting power to the PCM- it does eventually learn back the '0'
> condition, but is a very slow process. (paraphrased)
>
> 1991, 1993 and 1994 the PMC also relies on coolant temp in order to select
> the correct spark retard value table (they specifically leave out the 1992
> in this statement).
>
> Maybe some of this can set you on the right track to finding your problem.
>
> "K. Daver" > wrote in message
> . ..
>
>>Ok gang... Here's the deal:
>>
>>Went to the mechanic (he specializes in GM and I trust him
>>wholeheartedly)... although he's not a specific Saturn mechanic. We (and
>>by WE I mean HE) read the codes and it popped up with a 53 and a 45. He
>>wasn't sure if they had not been cleared, or if they had been caused, by a
>>previous dealership visit. So, he cleared 'em anyway. We changed the O2
>>sensor. The jerking and "misfiring" still happened. We (HE) checked the
>>codes again, and nothing popped up on the computer.
>>
>>I'm going to drive it for a few more days to see if anything will pop up
>>on the scan tool. Any ideas on what the code 53 is? He thought it was
>>the computer and the 45 was the O2 sensor.
>>
>>I searched on code 53 via Deja and someone, a while ago, posted it as
>>being ECM related on a 1991 or 1992. As this is a 1993, I didn't know if
>>that still applied.
>>
>>Thanks again everyone!
>>
>>Marty (remove NOSPAM to reply privately)
>>
>>hoosier_drifter wrote:
>>
>>>You can get the codes read for free at autozone and pick up any parts you
>>>need at about as cheap as you'll find anywhere. One trip, possible
>>>solution.
>>>
>>>As to ECMs going bad...
>>>They don't go bad on their own very often; that much is true. However,
>>>other factors can lead to them failing due to stress' inflicted by poorly
>>>done maintenance, broken casings, other bad parts, or when they do have
>>>problems it usually happens with increased heat that triggers expansion.
>>>The expansion causes defects in materials or poor assembly to come apart
>>>and
>>>loose conductivity. This happens even in military grade ICs and
>>>components,
>>>and as an engineer and technician I've seen plenty of these 'rare'
>>>ocurrences.
>>>
>>>I'm not telling you to go straight to swapping parts, I'm telling you to
>>>go
>>>to an 'experienced' mechanic/technician with Saturns to have it checked
>>>on,
>>>or read the codes at Autozone for free and take a stab at fixin' the
>>>situation yourself. That is all! The ECM/coil pack experience I had was
>>>just an antecdote, harping on a few Mr. Goodwrench guys at Kenny Kent in
>>>Evansville, IN...
>>>PS... I know some good mechanics there as well, but Larry, Darrell, and
>>>Darrell there soured me a bit.
>>>
>
>

I find it funny that people have to make suggestions to their mechanics and
tell them what to look for, and see nothing wrong with it.

After all, you don't usually go to a doctor, who sends you home saying he
doesn't know what the problem is, only to do research on your own to visit
him again in order to tell him what the diagnosis is. Most of us would hope
that his education, training, and experience would make him able to do that
without our help.

If it were me, I'd find another mechanic who has factory service manuals for
the car (where it sounds like the info below comes from) and the ability to
use them. Sounds like this guy does not.

Lane [ lane (at) evilplastic.com ]
---
Visit my Saturn Car Audio and Performance Page at http://www.evilplastic.com



"K. Daver" > wrote in message
m...
> Mike,
>
> AWESOME. Thank you very much for posting that! I'll forward that to my
> mechanic and post the results.
>
> Again, MANY MANY thanks..
>
> Marty
>
> Mike wrote:
> > No personal experience with it, but - Here is what my OEM 91-94
Electronic
> > Engine Controls manual says about code 53.
> >
> > Code 53 will set if the PCM is unable to eliminate engine knock by
retarding
> > timing. (i.e. the engine noise is most likely not due to spark knock) It
> > does not indicate a faulty knock sensor. Most likely causes Valve
lifter.
> > Belt Tensioner. Loose Bracket. Low Octane Fuel in high Ambient temps
while
> > pulling loads. Piston/Cylinder scuff.
> >
> > Once the knock condition is corrected, the code 53 should be erased by
> > disconnecting power to the PCM- it does eventually learn back the '0'
> > condition, but is a very slow process. (paraphrased)
> >
> > 1991, 1993 and 1994 the PMC also relies on coolant temp in order to
select
> > the correct spark retard value table (they specifically leave out the
1992
> > in this statement).
> >
> > Maybe some of this can set you on the right track to finding your
problem.
> >
> > "K. Daver" > wrote in message
> > . ..
> >
> >>Ok gang... Here's the deal:
> >>
> >>Went to the mechanic (he specializes in GM and I trust him
> >>wholeheartedly)... although he's not a specific Saturn mechanic. We
(and
> >>by WE I mean HE) read the codes and it popped up with a 53 and a 45. He
> >>wasn't sure if they had not been cleared, or if they had been caused, by
a
> >>previous dealership visit. So, he cleared 'em anyway. We changed the
O2
> >>sensor. The jerking and "misfiring" still happened. We (HE) checked
the
> >>codes again, and nothing popped up on the computer.
> >>
> >>I'm going to drive it for a few more days to see if anything will pop up
> >>on the scan tool. Any ideas on what the code 53 is? He thought it was
> >>the computer and the 45 was the O2 sensor.
> >>
> >>I searched on code 53 via Deja and someone, a while ago, posted it as
> >>being ECM related on a 1991 or 1992. As this is a 1993, I didn't know
if
> >>that still applied.
> >>
> >>Thanks again everyone!
> >>
> >>Marty (remove NOSPAM to reply privately)
> >>
> >>hoosier_drifter wrote:
> >>
> >>>You can get the codes read for free at autozone and pick up any parts
you
> >>>need at about as cheap as you'll find anywhere. One trip, possible
> >>>solution.
> >>>
> >>>As to ECMs going bad...
> >>>They don't go bad on their own very often; that much is true. However,
> >>>other factors can lead to them failing due to stress' inflicted by
poorly
> >>>done maintenance, broken casings, other bad parts, or when they do have
> >>>problems it usually happens with increased heat that triggers
expansion.
> >>>The expansion causes defects in materials or poor assembly to come
apart
> >>>and
> >>>loose conductivity. This happens even in military grade ICs and
> >>>components,
> >>>and as an engineer and technician I've seen plenty of these 'rare'
> >>>ocurrences.
> >>>
> >>>I'm not telling you to go straight to swapping parts, I'm telling you
to
> >>>go
> >>>to an 'experienced' mechanic/technician with Saturns to have it checked
> >>>on,
> >>>or read the codes at Autozone for free and take a stab at fixin' the
> >>>situation yourself. That is all! The ECM/coil pack experience I had
was
> >>>just an antecdote, harping on a few Mr. Goodwrench guys at Kenny Kent
in
> >>>Evansville, IN...
> >>>PS... I know some good mechanics there as well, but Larry, Darrell,
and
> >>>Darrell there soured me a bit.
> >>>
> >
> >

Not at all... very competent. He's just a friend of mine who is a GM
mechanic and teaches other classes (non-auto related) at night. He
doesn't do side work and isn't a specialized "Saturn" mechanic. So,
because he's doing it on his time, and not charging me labor, I try to
take care of as much as possible before bringing him the car, telling
him to drive it around for a week, and saying "fix it!" if the problem
resurfaces.

He does the same when he has a computer problem. Writes down all the
codes, glitches, etc., before he dumps it on me. Not that we don't know
what we're doing, but we don't have a lot of time to sit there and try
to "restart" the problem ourselves.

Just a matter of each one helping the other out due to our schedules...
nothing wrong with that...

Marty
Lane wrote:
> I find it funny that people have to make suggestions to their mechanics and
> tell them what to look for, and see nothing wrong with it.
>
> After all, you don't usually go to a doctor, who sends you home saying he
> doesn't know what the problem is, only to do research on your own to visit
> him again in order to tell him what the diagnosis is. Most of us would hope
> that his education, training, and experience would make him able to do that
> without our help.
>
> If it were me, I'd find another mechanic who has factory service manuals for
> the car (where it sounds like the info below comes from) and the ability to
> use them. Sounds like this guy does not.
>
> Lane [ lane (at) evilplastic.com ]
> ---
> Visit my Saturn Car Audio and Performance Page at http://www.evilplastic.com
>
>
>
> "K. Daver" > wrote in message
> m...
>
>>Mike,
>>
>>AWESOME. Thank you very much for posting that! I'll forward that to my
>>mechanic and post the results.
>>
>>Again, MANY MANY thanks..
>>
>>Marty
>>
>>Mike wrote:
>>
>>>No personal experience with it, but - Here is what my OEM 91-94
>
> Electronic
>
>>>Engine Controls manual says about code 53.
>>>
>>>Code 53 will set if the PCM is unable to eliminate engine knock by
>
> retarding
>
>>>timing. (i.e. the engine noise is most likely not due to spark knock) It
>>>does not indicate a faulty knock sensor. Most likely causes Valve
>
> lifter.
>
>>>Belt Tensioner. Loose Bracket. Low Octane Fuel in high Ambient temps
>
> while
>
>>>pulling loads. Piston/Cylinder scuff.
>>>
>>>Once the knock condition is corrected, the code 53 should be erased by
>>>disconnecting power to the PCM- it does eventually learn back the '0'
>>>condition, but is a very slow process. (paraphrased)
>>>
>>>1991, 1993 and 1994 the PMC also relies on coolant temp in order to
>
> select
>
>>>the correct spark retard value table (they specifically leave out the
>
> 1992
>
>>>in this statement).
>>>
>>>Maybe some of this can set you on the right track to finding your
>
> problem.
>
>>>"K. Daver" > wrote in message
om...
>>>
>>>
>>>>Ok gang... Here's the deal:
>>>>
>>>>Went to the mechanic (he specializes in GM and I trust him
>>>>wholeheartedly)... although he's not a specific Saturn mechanic. We
>
> (and
>
>>>>by WE I mean HE) read the codes and it popped up with a 53 and a 45. He
>>>>wasn't sure if they had not been cleared, or if they had been caused, by
>
> a
>
>>>>previous dealership visit. So, he cleared 'em anyway. We changed the
>
> O2
>
>>>>sensor. The jerking and "misfiring" still happened. We (HE) checked
>
> the
>
>>>>codes again, and nothing popped up on the computer.
>>>>
>>>>I'm going to drive it for a few more days to see if anything will pop up
>>>>on the scan tool. Any ideas on what the code 53 is? He thought it was
>>>>the computer and the 45 was the O2 sensor.
>>>>
>>>>I searched on code 53 via Deja and someone, a while ago, posted it as
>>>>being ECM related on a 1991 or 1992. As this is a 1993, I didn't know
>
> if
>
>>>>that still applied.
>>>>
>>>>Thanks again everyone!
>>>>
>>>>Marty (remove NOSPAM to reply privately)
>>>>
>>>>hoosier_drifter wrote:
>>>>
>>>>
>>>>>You can get the codes read for free at autozone and pick up any parts
>
> you
>
>>>>>need at about as cheap as you'll find anywhere. One trip, possible
>>>>>solution.
>>>>>
>>>>>As to ECMs going bad...
>>>>>They don't go bad on their own very often; that much is true. However,
>>>>>other factors can lead to them failing due to stress' inflicted by
>
> poorly
>
>>>>>done maintenance, broken casings, other bad parts, or when they do have
>>>>>problems it usually happens with increased heat that triggers
>
> expansion.
>
>>>>>The expansion causes defects in materials or poor assembly to come
>
> apart
>
>>>>>and
>>>>>loose conductivity. This happens even in military grade ICs and
>>>>>components,
>>>>>and as an engineer and technician I've seen plenty of these 'rare'
>>>>>ocurrences.
>>>>>
>>>>>I'm not telling you to go straight to swapping parts, I'm telling you
>
> to
>
>>>>>go
>>>>>to an 'experienced' mechanic/technician with Saturns to have it checked
>>>>>on,
>>>>>or read the codes at Autozone for free and take a stab at fixin' the
>>>>>situation yourself. That is all! The ECM/coil pack experience I had
>
> was
>
>>>>>just an antecdote, harping on a few Mr. Goodwrench guys at Kenny Kent
>
> in
>
>>>>>Evansville, IN...
>>>>>PS... I know some good mechanics there as well, but Larry, Darrell,
>
> and
>
>>>>>Darrell there soured me a bit.
>>>>>
>>>
>>>
>
>

Ok,

Here's the update: The mechanic cleared all the codes (I think it was
45 and 53) to see if my recent trip to the dealer caused any to trip
(had to have my ignition switch repaired in an emergency).

I ended up replacing the O2 sensor and the fuel pump. Both had been the
original ones since I bought the car (and had never been changed with
the previous owner). The codes never came back after he cleared them
from the computer, but the car still bucks.

Any suggestions? We're thinking to try putting a new wireset (although
we did change them before [for maintenance, not anything "wrong" persay].

Thanks again everyone!

Marty

K. Daver wrote:
> Mike,
>
> AWESOME. Thank you very much for posting that! I'll forward that to my
> mechanic and post the results.
>
> Again, MANY MANY thanks..
>
> Marty
>
> Mike wrote:
>
>> No personal experience with it, but - Here is what my OEM 91-94
>> Electronic Engine Controls manual says about code 53.
>>
>> Code 53 will set if the PCM is unable to eliminate engine knock by
>> retarding timing. (i.e. the engine noise is most likely not due to
>> spark knock) It does not indicate a faulty knock sensor. Most likely
>> causes Valve lifter. Belt Tensioner. Loose Bracket. Low Octane Fuel in
>> high Ambient temps while pulling loads. Piston/Cylinder scuff.
>>
>> Once the knock condition is corrected, the code 53 should be erased by
>> disconnecting power to the PCM- it does eventually learn back the '0'
>> condition, but is a very slow process. (paraphrased)
>>
>> 1991, 1993 and 1994 the PMC also relies on coolant temp in order to
>> select the correct spark retard value table (they specifically leave
>> out the 1992 in this statement).
>>
>> Maybe some of this can set you on the right track to finding your
>> problem.
>>
>> "K. Daver" > wrote in message
>> . ..
>>
>>> Ok gang... Here's the deal:
>>>
>>> Went to the mechanic (he specializes in GM and I trust him
>>> wholeheartedly)... although he's not a specific Saturn mechanic. We
>>> (and by WE I mean HE) read the codes and it popped up with a 53 and a
>>> 45. He wasn't sure if they had not been cleared, or if they had been
>>> caused, by a previous dealership visit. So, he cleared 'em anyway.
>>> We changed the O2 sensor. The jerking and "misfiring" still
>>> happened. We (HE) checked the codes again, and nothing popped up on
>>> the computer.
>>>
>>> I'm going to drive it for a few more days to see if anything will pop
>>> up on the scan tool. Any ideas on what the code 53 is? He thought
>>> it was the computer and the 45 was the O2 sensor.
>>>
>>> I searched on code 53 via Deja and someone, a while ago, posted it as
>>> being ECM related on a 1991 or 1992. As this is a 1993, I didn't
>>> know if that still applied.
>>>
>>> Thanks again everyone!
>>>
>>> Marty (remove NOSPAM to reply privately)
>>>
>>> hoosier_drifter wrote:
>>>
>>>> You can get the codes read for free at autozone and pick up any
>>>> parts you
>>>> need at about as cheap as you'll find anywhere. One trip, possible
>>>> solution.
>>>>
>>>> As to ECMs going bad...
>>>> They don't go bad on their own very often; that much is true. However,
>>>> other factors can lead to them failing due to stress' inflicted by
>>>> poorly
>>>> done maintenance, broken casings, other bad parts, or when they do have
>>>> problems it usually happens with increased heat that triggers
>>>> expansion.
>>>> The expansion causes defects in materials or poor assembly to come
>>>> apart and
>>>> loose conductivity. This happens even in military grade ICs and
>>>> components,
>>>> and as an engineer and technician I've seen plenty of these 'rare'
>>>> ocurrences.
>>>>
>>>> I'm not telling you to go straight to swapping parts, I'm telling
>>>> you to go
>>>> to an 'experienced' mechanic/technician with Saturns to have it
>>>> checked on,
>>>> or read the codes at Autozone for free and take a stab at fixin' the
>>>> situation yourself. That is all! The ECM/coil pack experience I
>>>> had was
>>>> just an antecdote, harping on a few Mr. Goodwrench guys at Kenny
>>>> Kent in
>>>> Evansville, IN...
>>>> PS... I know some good mechanics there as well, but Larry,
>>>> Darrell, and
>>>> Darrell there soured me a bit.
>>>>
>>
>>

If you think that there might be arcing, you have to replace the plugs and
the wires at the same time.

Why, you ask? Because if there is arc tracking along the plug wire and the
plug, then replacing one and not the other will still provide a pre-burned
path for the arc track to reestablish.


"K. Daver" > wrote in message
...
> Ok,
>
> Here's the update: The mechanic cleared all the codes (I think it was 45
> and 53) to see if my recent trip to the dealer caused any to trip (had to
> have my ignition switch repaired in an emergency).
>
> I ended up replacing the O2 sensor and the fuel pump. Both had been the
> original ones since I bought the car (and had never been changed with the
> previous owner). The codes never came back after he cleared them from the
> computer, but the car still bucks.
>
> Any suggestions? We're thinking to try putting a new wireset (although we
> did change them before [for maintenance, not anything "wrong" persay].
>
> Thanks again everyone!
>
> Marty
>
> K. Daver wrote:
>> Mike,
>>
>> AWESOME. Thank you very much for posting that! I'll forward that to my
>> mechanic and post the results.
>>
>> Again, MANY MANY thanks..
>>
>> Marty
>>
>> Mike wrote:
>>
>>> No personal experience with it, but - Here is what my OEM 91-94
>>> Electronic Engine Controls manual says about code 53.
>>>
>>> Code 53 will set if the PCM is unable to eliminate engine knock by
>>> retarding timing. (i.e. the engine noise is most likely not due to spark
>>> knock) It does not indicate a faulty knock sensor. Most likely causes
>>> Valve lifter. Belt Tensioner. Loose Bracket. Low Octane Fuel in high
>>> Ambient temps while pulling loads. Piston/Cylinder scuff.
>>>
>>> Once the knock condition is corrected, the code 53 should be erased by
>>> disconnecting power to the PCM- it does eventually learn back the '0'
>>> condition, but is a very slow process. (paraphrased)
>>>
>>> 1991, 1993 and 1994 the PMC also relies on coolant temp in order to
>>> select the correct spark retard value table (they specifically leave out
>>> the 1992 in this statement).
>>>
>>> Maybe some of this can set you on the right track to finding your
>>> problem.
>>>
>>> "K. Daver" > wrote in message
>>> . ..
>>>
>>>> Ok gang... Here's the deal:
>>>>
>>>> Went to the mechanic (he specializes in GM and I trust him
>>>> wholeheartedly)... although he's not a specific Saturn mechanic. We
>>>> (and by WE I mean HE) read the codes and it popped up with a 53 and a
>>>> 45. He wasn't sure if they had not been cleared, or if they had been
>>>> caused, by a previous dealership visit. So, he cleared 'em anyway. We
>>>> changed the O2 sensor. The jerking and "misfiring" still happened. We
>>>> (HE) checked the codes again, and nothing popped up on the computer.
>>>>
>>>> I'm going to drive it for a few more days to see if anything will pop
>>>> up on the scan tool. Any ideas on what the code 53 is? He thought it
>>>> was the computer and the 45 was the O2 sensor.
>>>>
>>>> I searched on code 53 via Deja and someone, a while ago, posted it as
>>>> being ECM related on a 1991 or 1992. As this is a 1993, I didn't know
>>>> if that still applied.
>>>>
>>>> Thanks again everyone!
>>>>
>>>> Marty (remove NOSPAM to reply privately)
>>>>
>>>> hoosier_drifter wrote:
>>>>
>>>>> You can get the codes read for free at autozone and pick up any parts
>>>>> you
>>>>> need at about as cheap as you'll find anywhere. One trip, possible
>>>>> solution.
>>>>>
>>>>> As to ECMs going bad...
>>>>> They don't go bad on their own very often; that much is true.
>>>>> However,
>>>>> other factors can lead to them failing due to stress' inflicted by
>>>>> poorly
>>>>> done maintenance, broken casings, other bad parts, or when they do
>>>>> have
>>>>> problems it usually happens with increased heat that triggers
>>>>> expansion.
>>>>> The expansion causes defects in materials or poor assembly to come
>>>>> apart and
>>>>> loose conductivity. This happens even in military grade ICs and
>>>>> components,
>>>>> and as an engineer and technician I've seen plenty of these 'rare'
>>>>> ocurrences.
>>>>>
>>>>> I'm not telling you to go straight to swapping parts, I'm telling you
>>>>> to go
>>>>> to an 'experienced' mechanic/technician with Saturns to have it
>>>>> checked on,
>>>>> or read the codes at Autozone for free and take a stab at fixin' the
>>>>> situation yourself. That is all! The ECM/coil pack experience I had
>>>>> was
>>>>> just an antecdote, harping on a few Mr. Goodwrench guys at Kenny Kent
>>>>> in
>>>>> Evansville, IN...
>>>>> PS... I know some good mechanics there as well, but Larry, Darrell,
>>>>> and
>>>>> Darrell there soured me a bit.
>>>>>
>>>
>>>