I have a 93' Saturn, the service engine soon light comes on , on & off, what is going on?

Question

I checked all my fluid levels ...all are good...car is not making a noise...but I noticed lately my gas gauge is not working like it should...could that be the problem? And what causes this? Do I need a new gas gauge?

Answer 1

It's blinking on and off because Saturns models between 1991-1995 had the OBD-1. 1996 and after had the OBD-2.


(Directions posted by amazinghl fromt he Saturnfans.com Forum):
Use a paper clip to jumper Terminal A and B of the ALDL *Assembly Line Diagnostic Link* which is above your left knee.
Terminal A is an interal ground and is the top right terminal in the connector. Terminal B is directly adjacent and to the left of Terminal A.

Turn the ignition to ON.

All codes are 2 digits between 11 and 99. Codes are displayed on the SES light by flashing the light with short and long pauses to distinguish digits of one code from digits of another. The short pause is used between digits of the same code, long pauses are between codes. Also, each code is flashed three times before going to the next code.

For example, the sequence of code 12 will be: flash, pause, flash-flash, long pause, then repeat 2 times. If Code 12 is not displayed, the self-diagnostic pogram i snot functioning properly.

If only Code 12 is displayed, no system malfunctions have been stored.

Any existing system fault codes are displayed in order from low to high, except for Code 11.

On vehicles with an automatic transaxle and on which exist stored transaxle codes, Code 11 will be displayed last, then the SHIFT TO D2 light will begin flashing transaxle codes of flags.

When all engine codes have been displayed, Code 12 will flash again.

Here is a list of codes copied from a post by Wolfman on the saturnfans.com/forum (Thanks to the Wolfman!):

Information OBD I Codes (1991-1995 Saturns)
11 Transaxle Codes present
12 Diagnostic System Check
13 Oxygen sensor, circuit open or not ready
14 Engine coolant temp. circuit. Temp. out of range high
15 Engine coolant temp. circuit. Temp. out of range low
17 PCM fault, pullup resistor
19 1991Perf. (LLO) 1992-1994 vehicles. 6X signal fault
21 Throttle position circuit out of range high
22 Throttle position circuit out of range low
23 Inlet air temp. (IAT) out of range low
24 Vehicle speed sensor (VSS) circuit, no signal
25 Inlet air temp. (IAT) out of range high
26 Quad Driver output fault
32 EGR system fault
33 MAP sensor circuit, out of range high
34 MAP sensor circuit, out of range low
35 Idle air control rpm out of range
41 Ignition control circuit open or shorted
41 A EST circuit open
41 B EST circuit shorted
42 EST bypass, open or shorted
42 A Bypass circuit grounded
42 B Bypass circuit open
42 C Bypass circuit shorted
43 ESC (knock sensor) circuit open or shorted
44 Oxygen sensor indicates system lean
45 Oxygen sensor indicates system rich
46 Power steering pressure switch circuit, open
49 Idle rpm out of limit high (vacuum leak)
51 PCM memory error
55 A/D convertor error in PCM
81 ABS message fault (1993+ vehicles with TCS)
82 PCM internal communication fault

TRANSAXLE CODES

13 Line pressure high (1992 & 1994 vehicles)
14 Line pressure low (1993 & 1994 vehicles)
16 No 1st gear
18 No gears available (1993 & 1994 vehicles)
21 2nd gear stuck on
22 No 2nd gear
23 No 3rd gear
24 No 4th gear
25 No TCC
26 TCC stuck on
31 Transaxle temperature circuit open (cold)
32 Transaxle temperature circuit grounded (hot)
34 ECM communications failed (1991 PERF [LLO], 1992-1994 vehicles)
35 No turbine speed sensor signal
36 Turbine speed sensor signal noise
41 No vehicle speed sensor signal
42 Vehicle speed sensor noise
43 Actuators lost power.
43 Master enable relay open/grounded (1993 vehicles)
43 Master enable relay open/grounded (1991 & 1992 vehicles)
44 Master enable relay shorted to voltage (1993 vehicles)
45 Selector switch - no data
46 Selector switch - undefined data
48 Hold mode voltage low (1991-1992 vehicles)
49 Selector switch - invalid data (1991 PERF [LLO], 1992-1994 vehicles)
52 Hold mode stuck on (1991 & 1992 vehicles)
53 Hold mode stuck off (1991 & 1992 vehicles)
54 A/D failure
55 Transaxle temperature resistor failure
56 Generic FET driver failure (1991 &d 1992 vehicles)
75 3rd gear stuck on (1993 & 1994 vehicles)
78 4th gear stuck on (1993 & 1994 vehicles)

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Follow the source link posted below and you'll find possible diagnoses for your SES Light (posted by Low Saturn):
http://www.differentracing.com/tech_articles/diag_info.html
http://www.differentracing.com/tech_articles/dtc_chart.html
http://www.differentracing.com/tech_articles/ttc_chart.html

Answer 2

I dont think 'service engine soon' and 'check engine' are defined anywhere as far as having to have one or both on a car. They may mean different things on different makes and models. I think the OBD2 standard (which started on all cars sold in the USA in 96) only defines a MIL. MIL stands for Malfunction Indicator Light. I have owned cars in the past that has something like a check engine and a service engine now light. Many models do have some sort of service reminder light to remind you to do some maintenance items but its usually not the same one that tells you that something is broken. A flashing light usually indicates that the problem is occurring at the time or is a more critical issue. A steady light is a less critical issue or a critical issue that is not occurring at the time. It depends on what the code is how many times the problem has to happen before it trips the light and then how many key cycles or miles it has to go without seeing the problem again before the light will turn off. Some codes will not self reset. You need to look up the codes for your specific model and it should tell you what the condition is to set it and what it takes to turn it off. Many parts stores will read the codes for free or loan you the tool to do it yourself. Higher end models often have a way to read the codes without the tool. You can find out what the code was and decide if its worth taking it in or just waiting for it to get worse.

Answer 3

This Site Might Help You.

RE:
I have a 93' Saturn, the service engine soon light comes on , on & off, what is going on?
I checked all my fluid levels ...all are good...car is not making a noise...but I noticed lately my gas gauge is not working like it should...could that be the problem? And what causes this? Do I need a new gas gauge?

Answer 4

93 Saturn Sl1

Answer 5

Could be many things. Oxygen sensor, or PCV valve come to mind first. It is older, but I think '93 Saturns have a data port on the computer. Garage should be able to read the codes and tell what is wrong.

Answer 6

Most likely when it goes on and off like that its an oxegen sensor. Only way to know for sure is to read the codes. Some parts stores do it for free.

Answer 7

you have an intermittent emission control problem. it won't hurt to keep driving the car but you need to get it to a shop or someone to diagnose the problem or it will get worse and then could cause more trouble. good luck

Answer 8

take car to autozone, advance auto or some other parts store and they will check it for free and tell you what is wrong plus this will save you a lot of money some work you can do yourself or they might put a part on for you

Answer 9

It is probably just a senser that is off. Take your car to a mechanic and they will hook it up to a computer and they will be able to see which sensor is causing it.

Answer 10

Low engine oil?
Faulty alternator, or loose wire?