my saturns acting up. low rpm acceleration, miss, stumbles, bogs

[Rogers]

Hey guys having issues with my Saturn.

It's a 93 sc2 1.9l Twin cam 5spd

I've had a persistant code 32 with this Saturn and my previous Saturn...ive changed the egr valve and solenoid more than once with both cars and have never been able to get rid of it.

Now I've picked up a code 26... The ses light comes on after the vehicle has been running for about 20 seconds.

My symptoms are hesitation,backfiring through intake, sputtering, missfire ect. Basically it falls flat on its face when I take off and when getting back on the accelerator after shifting. It will fall on its face for a second and then pick back up with no problem. It does burn some oil but nothing like it did with the old motor.

Any ideas?

[Smoove]

I am dealing with the same crazy stuff in my truck. I have changed all kinds of parts and not fixed the problem. My next part test is going to be the Idle Air Controller (IAC). Then a throttle position sensor if the IAC doesn't fix it.

[tejarillo]

First of all change spark plug and spark plug wires then buy a cleaner for injector that will take care of it

[Ian01]

change plugs then fuel filter, 8 times outta 10 it's about that time annyways, what do you have to lose.

[Smoove]

First of all change spark plug and spark plug wires then buy a cleaner for injector that will take care of it

I wish mine was that easy. I have replaced distributer, plugs, coil, spider injectors, wires, egr,fuel pump, fuel filter.

Edited January 22, 2012 by Smoove

[Rogers]

Plugs are new a week ago. Wires are about a year old but are aftermarket...I've got plenty of wires laying around so ill try them. My next plan of action is the tps and map sensors along with the vacuum canister possibly

[sayhuh?]

Yea, plugs and wires and anything else associated with it.

Also, found this for your code 26

Code 26 (according to Haynes):

> Quad Driver output fault

>

> Possible cause: The PCM detects an improper voltage level on the circuit that

> is connected to the Quad Driver Module.

>

> Now, my questions are... What IS the Quad Driver Module, what does it do, and

> where is it?

Pretty vague, isn't it?

First of all, don't panic. Usually, this is not a serious

problem. Let me explain.

Code 26 is a *very common* SES indication to get with a Saturn that

has a few years on it. Most of the solutions, luckily, are not costly.

However, this may depend on the year of your car.

Background

----------

The "Quad Driver" is a device in the computer that "drives" electro-

mechanical devices in the car. Computers run with very little current

(milliamps or microamps) in their circuits. But the devices that

turn on your cooling fan, bulbs, or emissions relays may require

current in a higher range, say tenths of an amp.

Thus, the computer can't talk very well with such a high current

device. It needs help, and it gets in in the form of this Quad Driver

device. The computer sends a signal (very low amps) to the driver, and

it in turn then signals the electromechanical device to do whatever it

needs to do with a higher current which that device can use.

It sort of "drives" the device by remote control.

Code 26

-------

OK, fine, that is the theory. So why the code 26? Well, in almost all

cases, the actual driver device does not fail. What fails is one of

the electro-mechanical devices attached to it. The way the SES light

works, it will come on when either one of the driven devices fails or

if the driver itself fails.

The good news is it is usually not the costly driver device. The bad

news is this is called a "QUAD" driver. That means it drives four

devices. Even worse, there are usually TWO quad drivers, so you have

a total of EIGHT devices to check for just this one SES light.

That's right, code 26 means that one of 8 devices (and a 9th, the driver

itself), could cause the problem. You have to check 8 different things.

Probable causes

---------------

I don't have my manual here, but I'll try to remember to post the

exact devices to check. The following is from memory, so bear with me.

Also, remember my car is a '91, so this may have changed somewhat in

following years.

The QD generally drives things like relays, solenoids and light bulbs.

There are a few things that are easy to check, like the bulbs and

relays.

The SES bulb and (I think) "HOT" bulb are driven by this device. You

should check that they both come on when you put the car to "on" before

starting. Of course, the SES must work, since it came on for you.

Then the A/C relay and Cooling fan relay are driven. For A/C, simply

check that your A/C works OK. The relay is pretty silent, unlike

some cars, so you can't always hear it click. Just make sure it works.

The cooling fan can be checked when you sucked out the code. Since you

know how to get the code, you should have noticed that the FAN comes

on for a while before getting the code out. (The bulbs also light.)

If the fan isn't coming on, check the relay. The Haynes manual probably

tells you exactly when the fan comes on during the procedure.

The relay is accessible in the under-hood fuse block.

After that, it gets tougher. You have to check some emissions solenoids.

From what I've read, the MOST COMMON cause of code 26 is either the

EGR solenoid or the canister purge solenoid. The EGR solenoid is

real easy to access. It sits right above the EGR valve and takes a minute

to disconnect on Sx2 models. The canister purge solenoid is a pain.

It is attached to the block on the firewall side. You have to take it

out blindly by putting your hand through a small "hole" between all the

hoses and wires.

I forgot what else is controlled by this device. I'll try to get

my manual tonight to look.

I had an SES light last spring. In my case, I guessed wrong.

I narrowed my SES last year down to the CPS or the EGRS, and incorrectly

deduced the CPS. What a pain to replace this. But I was wrong. That

wasted $20. My problem was the EGRS, and it was also a $20 part. Very

easy to replace.

I should mention that my symptoms were opposite of yours. Mine would

come on only while driving for a while, then go off when I stopped.

I should also mention that the CPS and EGRS are common causes of

code 26, and the irony is they are both Nippondenso parts, made in

Japan. How ironic!

Either way, if you take it for service, the Saturn diagnostic computer

should be able to discern between the two or any other device that

is causing this code. They can read more information than we can

by just pulsing out codes.

So, depending on your skill and your luck, you may or may not want to

try this. Like I said, most of the them are easy, thus even if Saturn

service does it, it usually is not costly.

==== Quote Off ====

And a followup:

==== Quote On ====

This is a follow up to yesterday's post about a "quad driver" fault.

Yesterday I mentioned the causes for a "code 26" fault with the

SES light. There I detailed the following causes:

1) SES light burned out

2) "HOT" light burned out

3) A/C relay

4) Coolant fan relay

5) EGR solenoid

6) Canister purge solenoid

I couldn't remember the other two causes. Remember, the "quad" in

the driver means it controls 4 outputs. Since there are 2 QDMs,

they control 8 outputs.

The other missing items to check are:

7) Speedometer output

Upshift/Shift to D2 bulb

[optical]

plugs/wires/fuel filter. check for vac leaks. get the tps checked and maf and possible get cat checked

Edited January 22, 2012 by optical

[sayhuh?]

http://saturnwiki.net/index.php/26_Quad_Driver_Output_Fault

[Rogers]

Thank you for all of the info sayhuh? It's supposed to warm up a couple days this week so I'm going to have to get my dmm out and start checking these circuits. It's irritating that both codes tell me the same list of crap that could be wrong. I know my vacuum hoses are good since I just replaced them when I changed the motor. I didnt get the code 26 till I hit the.deer a few weeks ago. I think the purge canister is up there somewhere