Hello,


Been using the forum for a short time and found many useful bits of info. Thanks.


Recently purchased a 1997 Sl2 and have had pretty good luck with it so far. I have been chasing down a service code and SES light problem. The code comes out as a po105 MAP sensor. I replaced the sensor itself and the connection looks good . Light will many times go off while driving, sometimes for the whole duration of use, but always comes back on with the same code. Sometimes it's accompanied with a cam sensor or crank sensor code...? Am I missing something thats common on these cars.


Any help or suggestions will be appreciated.


Thanks, Eric

1997 Saturn does not have a cam sensor and if the crank sensor was bad, the car would not run. The error code refers to the DIS (disrtributorless ignition system). New spark plugs/ignition wires/ and cleaning the ICM (ignition control module) should fix the error code. ICM can loss it's ground due to corrosion and the terminals can also corrode. Cleaning the four bolts that hold it to the engine as well as the engine/ control module interfaces can restore proper function. Dielectric grease works well to keep surfaces from further corrosion. Basically there is a misfire that the computer is picking up, even though you do not notice it.

Thanks paulorlo,


I'll try the new plugs and cleaning the connections. The wires look to be new. Thanks.


Any ideas on the MAP code? I did already replace the sensor


Thanks, Eric

Not familiar with that code (P0105) My Haynes manual lists P0107 and P0108 as manifold absolute pressure (MAP) sensor circuit low or high input. I know that some people have had problems with a leaking intake manifold gasket and they found the problem by spraying fluid around that gasket and noticing a change in engine idle speed.

PO105 ( MAP/BP(barametric Pressure) CircuitMalfuntion. Check the wires going to the Map sensor you just replaced. Sometimes the connector looks clean but the terminals are coroded. Corrosion may not be evident but I would scrape the terminals anyway. If that doesn't fix it, get a manual and diagnose the circuit to that connector. If you are not familular with diagnosing electical components, have someone help you who is.Or take it to a pro. If it is throwing random codes like crank and cam sensor and is off and on I would say it is a short at either the PCM or at the MAP connector.Edited by: answerman

pualorlo, I have found that Haynes manuals are not much good for anything else but to wipe your--- with. And its not very good for that. They lead you on a wild goose chase with (see section 5 in order to read section 4, but read section 2 before reading section 1.) and so on and so on. If you want a good informative manual try Mitchell or Alldata. Mitchell and Alldata are expensive though. Chiltons are made by haynes but are relativly easy to read and has a lot better descriptions at a cheaper price. If you want to stick with Haynes then see section 3.lol

Thanks for the input. I'll do some contact cleaning and go from there.


Thanks again, Eric

If it is not an issue at the connector:

MAP sensor code may indeed indicate that the manifold pressure is out of range (as far as the PCM is concerned). If this was the case, I would suspect vacuum leak at intake manifold or where throttle body/intake gasket -- these would both be sources of air that bypass the normal air intake path and therefore the MAP sensor.

What is RPM at idle?

Use throttle body cleaner to spray the areas described above while the car is running--if the idle changes, you've found the leak. If not, you've ruled out one more possibility.

Derf

Yes, it is possible to get a MAP code from a manifold or vacume leak. But that would be PO106 not PO105. 106 is the code for MAP out of range. 105 is the code for MAP circuit malfuntion. Check this web site for OBDII codes. It is dead on to my scanner codes. http://www.obdii.com/codes.html


With all due respect. Just trying to give some helpfull info.


Edited by: answerman

Sometimes a malfunction code that sets first may inhibit other codes (out of range high, low) from setting--depending on their relationship and which one sets first.

For example, when I had a cylinder going down, I found that if the misifre code for that cyl would set first, I would not receive any other codes for quite a while and the car drove smoothly. However, when I cleared the code, often I would get a cam code followed by a cyl misfire code -- sometimes even a "random cyl misfire" code -- which would adjust the timing to failsafe mode and make the car jerk on accel.

My point is that the logic routines on the PCM are often set up to prohibit further self-diag of a particular system once one of the codes related to its operation is set.

I agree that the MAP sensor malfunction code would lead me to initially believe either there is a problem with the MAP sensor itself or the circuit between it and the PCM (or the PCM input/outut portion which handles this subsystem. But he's already changed the MAP itself and is checking the connection/wiring issue.

Just trying to point out that what you see is not always entirely what you get/have/think you have.

I hope it is just the wiring....

Derf