ECM interchangability

My '93 SL2 has a high rev problem. It goes up to about 3000 in idle
and stays there until the car comes to a complete stop. I have cleaned
the throttle body, replaced the EGR valve, replaced the engine coolant
sensor and connector, replaced the idle speed control module. My
mechanic was baffled as well. The ECM doesn't tell him anything
useful. It is our opinion that the ECM has probably gone bad. So I
ordered one from 6th Planet - on August 28th to be exact. An ECM
showed up on October 17. Mine was a 48 state part. The new one is a
California part. The conector keys are different. 6th Planet has
ignored several emails. I am not at all pleased. Question: can I
just remove the keys and use the California part?

 

6th Planet has ignored several emails. I am not at all pleased.

Well, that's not very good business if that is the case.


Can you post the numbers on the label on the PCM you just bought so we can
determine its year? Generally, if the connector is different, then the
wiring is different as well and it is NOT plug-and-play. At best, you would
have to re-wire something, and most people would not want to attempt that.
There is a swap guide here, but I don't know if it will tell you much about
your current situation:

http://www.saturnspot.com/forum/viewtopic.php?t=19927

Even if you receive a PCM that does match up for the connector & year range,
it still usually need to be reflashed for the options that exist on your
car. Otherwise, it may not work properly. I when through this when I
swapped the engine & replaced the PCM in my '92.

Personally, I'd be AMAZED if your condition was caused by something
malfunctioning in the PCM. Watching this newsgroup for more than ten years
and being an owner for 13+, I have never heard of anyone who reported theirs
went bad.

A California PCM probably has more restrictions for emissions compared to
the federal version. I believe the CA & NY cars have additional equipment
you may not have (air pump comes to mind, and the close-coupled cat that's
in the exhaust manifold itself as well). I don't know this for sure, but
I'd suspect there may be a slight mileage difference between them as well.

Is your mechanic a Saturn tech at your local Saturn retailer? If not,
consider taking it to them. I've found them to be well worth the diagnostic
fee they charge because they've been dead on for all the oddball problems
I've taken to them over the years that I was not able to diagnose myself.

Lane [ lane (at) evilplastic.com ]

 

Hi Lane,

Here are the numbers from the two computers:

Old:

21022241-21022245 21021855

New:
21022767 21022422

The old one is marked PERF-MAN.

The new one is marked PER-MAN-CAL.

My mechanic is not a Saturn mechanic but has kept mine going for 13
years. I will take the car to the dealer. That's a great idea.

Thanks!

 

According to the Saturn factory parts manual...

21021855 is for a '93 DOHC with manual trans.
21022422 is for a '94 DOHC with manual trans w/ california emissions.

So, looks like the numbers match what you expected.

You may have to depend on luck-of-the-draw with the Saturn tech you get.
The average one may tell you it is for a different year than your car and
you can't use it. In fact, I suspect they may even say it is illegal and
they can't help you with it because you're modifying the emissions system by
swapping it. BUT, if you get a great tech, they will break out the factory
service manuals and determine why the connectors are diffferent, and how
involved it would be to modify your car's wiring to accomodate. This is
something you could do as well if you wanted to, as the factory service
manuals are a part you can purchase from your local Saturn's parts
department. Or, you can see them on eBay once in a while too.

I have some spares I keep on hand for my race car, and a quick look at the
PCMs connectors for the '93 vs '94 show them to be the same. BUT, neither
of mine is a CALIF so I have no idea what variable that throws into the mix.

If I were you... I'd return it and get the correct PCM. Or, if that isn't
an option, find the correct one elsewhere. Again, eBay is a great place to
look.

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

 

I hate to sound like a one trick pony.
But I believe the problem is a bad Coolant temperature sensor.
I've had the exact same problem with two consequetive Saturn SC2s.
Thing has been a complete stumper for "professional mechanics".

I honestly believe that this was a flaw added to the engine design so
that every single one would be off the road 10 years after leaving the
showroom!

Without this eventual cooling induced problem - most Saturns would last
200 to 300 thousand miles with decent care.

-WaV

PS - Is there ANYONE out there that has a working odometer past 100,000
miles?
The instrument cluster is CRAP cheap plastic that wasnt MENT to last 10
years.
I went out in the junkyard to find ONE electric drive gear for the
odomenter...
EIGHT were screwed up out of EIGHT that I took apart!

General Motors - I Like the products, I HATE the company.

 

PS - Is there ANYONE out there that has a working odometer past 100,000

Both of my Saturns have never had a problem with the odometer (157k on the
'94, 148k on the '92).

Lane [ lane (at) evilplastic.com ]

 

Do you keep them indoors?
Maybe its the Texas climate. Heat gets incredable inside a baking SC2!
(I've measured 160.)

PS. Never never reset the trip odometer while moving. That's what
happened when mine stopped (a 1994) - also have heard same with older
model Porches.

-WaV

 

My son's car has to have 190,000+ miles on it by now. Odometer is still
working.

Ken
Clarksville, Michigan

 

The '92 I bought used, so I don't know if it was garaged but It was owned by
a college student so I'd guess probably not.

My '94 was kept outdoors for the first 5 years seeing -30 to 95 degrees F.
Now it sees 30 - 95 degrees. And yes, that minus 30 is a true minus 30.
During the outdoor years, I do remember a few windchill advisories in the
minus 50s also. Even with those wide variations, I haven't had a problem
with the odometers.

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

 

This is strange. I wasnt kidding about actually taking 8 units apart.
Out of 5, BOTH the larger 15 tooth AND the smaller one were broken.
Even the 15 tooth gear on mine fell apart after being handled too much.
On the 3 I retained with intact 15 tooth gears, they all have cracks in
them.
One has a crack than runs right through the tooth - I think I'll pass
on that one and decide on one of the other two...
I wonder what I could do to make these questionable keepers stronger
and last longer? Glue? Tape? Cut a new one out of a bottle cap with a
micro file?

It must have to do with UV and heat. I'd bet a closed Saturn attains
temps over 100 degrees more than 6 months out of the year! Maybe
more... I mean - far more significant killer temps down here where it
only freezes maybe a week out of the year.

What made removal of most of these inst clusters a lot easier was the
fact that even the mounting plastic on these yard-cars is so brittle
that I seldom had to unbolt them - After prying off the top dash cover
section, I'd give the cluster a couple of yanks and break it right out.
Crumbly, even.

Well - Gears are available for $30 with gearsonline.com...

-WaV

 

Of the last 4 cars I have had, only my '93 SL2 has NOT had this
problem. 2 of them are Volvos! They seem to be able to bulid a car
that can run a million miles but odometers that break at 150K. In each
case, new gears did the trick.

Terry

 

Well how about that? I would have thought if ANYone had sufficiently
done "longevity testing" it would have been the Swedes from Volvo.
ON THE OTHER HAND - My brother used to have an old 240 or whatever they
called those four-door boxes... After replacing part after part at WAY
much higher cost than Japanese or American car parts - he exclaimed to
me that there's nothing special about Volvos that make them million
mile cars - its just that its built so that every single tiny little
part is individually replaceable. IE. Greater number of serviceable
parts = more parts revenue.
-WaV

 

Pfft... Work on cars for a living and you will throw that superior
because of origin or nameplate crap out the window.

 

Well, its just that Volvo used to have a "reputation" for cars that
lasted forever.
Maybe it was all just a advertising ploy that "worked". I do remember
some ads where they'd tell about some old geezer who's put like
1,200,000 miles on his old Sedan.
Longevity isnt sexy anymore though. If your car isnt "nearly new" you
just aren't cool. No matter how well engineered it is.
Oh well!
-WaV

My old aquaintances in the group 'Trout Fishing in America' toured in a
old red Ford F-150 (named Robert, of course) for at least ten years and
racked up close to 1,000,000 miles in it. Yeah - I dont remember
anyone going on about how long Ford trucks last - not in a while!

 

What you or they call a reputation I call a myth. I've seen plenty of
vehicles at near or above 1,000,000 miles of every kind and others of
the same type ready for the junk yard before 100,000 miles. It makes
little to no difference who makes it! It matters how often you drive,
how you drive it, and how well you care for it!

The people who spend big bucks buying these overpriced European cars
usually do what with them??? They stick them in a garage every night and
every time they have a "small" issue they go straight to the shop and
don't mind one damn bit dishing out big bucks to get it corrected. How
many people do you know with a Chevy that will go straight to a shop
when the check engine light comes on? How many people with a Chevy have
every joint greased regularly? How many people with a Chevy get a tune
up when it's needed and not when it "no longer starts"? How many people
with a Chevy? DO YOU GET MY POINT! My cousin has a nice low mileage
Volvo that has been sitting for years. Why is it sitting? Because he
doesn't want to spend more than a grand getting the rear main seal
replaced... EOD