Saturn S series Traction Control Systems -- How do they Operate?
 

I've been doing some research to determine if it is worthwhile to back-enable the Traction Control functionality that has likely been lurking in my old 95 SC2 5sp.

Assuming the wiring harness to the pod switches is the same w ABS and ABS + TRAC configurations, repinning of the connector to match a 2nd gen 3 switch pod w a TRAC button, addition of a relay + fuse(?), and a PCM flash may enable TRAC control, yes?

All input welcome on the above.

I am now trying to determine HOW the S series Traction control operates.

I know on later vehicles in general (esp once throttle cables vanished), a combination of timing retardation AND ABS activation (braking on the drive axle) is used to reduce wheel slip when one of drive wheels starts to slip.

However, I have read that the S car implementation -- at least for the earlier gens (1st, prob 2nd gen) - that traction control consisted ONLY of using the ABS wheel speed sensors to detect wheel spin, followed by engine timing retardation to reduce engine power output, thus helping to slow down the the spinning wheel and maximize traction.

My 97 owner's manual seems to bolster this, as it states (pg 133):

"Your Saturn has a traction control system if it is equipped with an anti-lock braking system (ABS). The traction control system limits wheel spin and is especially useful in slippery road conditions. The system operates only if one or both of the front wheels are spinning or beginning to lose traction. When this happens, the system will reduce engine power to limit wheel spin. The system works in both forward and reverse gears and at all speeds".

(In 97, if you chose the ABS option, TRAC came with it. NOT true for 95.)

I find TRAC to be especially helpful in slow moving slushy situations where launching from a stop would otherwise mean wheel spin any time I want to move from a stop. Contrary to other comments I have read, this kind of traction control CAN be helpful ins SOME deeper snow conditions; if nothing else it helps you to launch in a relatively straight direction because the right front wheel spin is reduced until it gains some traction, then the LD differential adds the left front wheel to the mix and the two wheels are pulling at about the same speed. Without it, the right front spins and spins, slowly carving you a path to the right.

So is it therefore correct to assume that the 95's system would operate identically?

I thought you gave the 95 to your nephew, derf. I would THINK it would operate identically, but have NEVER messed with one. Never really felt the need for it in TN nor here in Hell, I mean, FL.

He has parked it, so it is idle. Has another vehicle to drive. I may have him gift it back to me. Right now it has no plates.

I will then try to fix the timing on the exhaust cam. If it runs properly after that, I will take it back and have a spare car again. If not, tear it down and rebuild the top end -- I've always wanted to crack open an engine and rebuild it. If not, maybe I'll drop an LSJ in it from a wrecked redline. Just have to rebuild the frame under the hood to support it and mount it, Oh and the tranny too.
-----------
I'm sure Andy and I can have 16 hour skype sessions with every weekend (NOT).

He'd just end up saying "NO! Don't do THAT....do THIS like I just told you, dumbass".

-----------
Actually my bro in law is quite well versed at things automotive and motorcyclular ( motorcyclic?).

But it's be nice to have TRAC for the sloppy days around this area given all the hills n such. It made a significant difference when driving the 97 in WI where the snow gets packed but then melts at the intersections from everyone stopping . Don't even use 1st gear in the winter.

Actually the key to driving in WI is to NOT STOP.....momentum is your friend. Drivers know to leave a whole mess of room between cars when it's snowing and slippery, so if you see a red light up ahead, you just let up on the throttle to time it so that the light is green when you get to it. If you absolutely will strand yourself by stopping at a red light, you look very carefully for cross traffic, and if there is none, you slowly go through the light. Some people toot their horns if the visibility is complete crap.

I believe you can tell an officer of the law that you did not feel you could stop your vehicle in a safe manner so you cautiously proceeded through the intersection.

I'd rather get a ticket than be stranded. Which, after being pulled over, I guess I would be anyway. But I'd have good company to help me.

Derf
My 94 has traction control and I really have never taken the time to read how it works. Do you want I should pull out the owner's manual and see what it says? Traction never has been a problem in Phoenix so I just leave it off.
On the other hand, my 2015 Dodge Caravan has traction control and however they have the thing set up to work, it seems as if there is as little as dew on the road the tires spin frantically for now logical reason at all but it develops close to 310HP and has a 6 speed transmission. That combination is a bit weird to drive with front wheel drive.

Maybe you should put some slicks on the front of your Dodge and warm them up before getting out on the open highway, Unc! LOL

It uses the abs wheel speed sensors to detect slippage (loss or beginning of losing traction). The newer systems use a combination of retarding the timing and applying thee brake (pulsing) on the affected drive axle to combat the tire spinnage.

To answer my own question:

The TRAC in the earlier S cars was based only on timing retardation.

That is pretty much what the owners manual says for '94, that and the gears in the differential. What ever that is supposed to mean.

The one feature of this car, unique to any that I have owned until now was the sport shift option on the automatic transmission.
When in Sport mode, it started out in first rather than 2nd and the shift points took place at a higher rpm.
My Dodge has that feature now too except the transmission is not quite as civil about doing things as the Saturn does. It's fussier how it starts out but from there on up is is the same. Just 2 more gears though as it is a 6 speed.