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Discussion Starter #1
MAF sensor:

Pin 1-3 -- ~12.5 VDC, 14.5 with car on
Pin 2 and ground -- 2.65 VDC voltage does not change with RPM
This is a malfunctioning sensor, no?
What is it suppose to read?

turbo pressure temperature sensor:

Pin 1-4 -- 2.02 VDC idle or engine off -- ~3,000 RPM 2.1 VDC
Pin 1-3 -- 5.04 VDC voltage does not change with RPM
Pin 1-2 -- 3.5 VDC voltage does not change with RPM
This is a malfunctioning sensor, no? Or maybe leak somewhere I guess.
What is it suppose to read?

I do not know which way the pins are numbered.

CODES:
P2138
P0325
P2304
P0119
P2123
P2127
 

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I don't know why u r testing those circuits, as these codes have nothing to do with these components.

u have 2 faults for the accelerator pedal sensor (there is a famous grey connector under the battery that could be corroded, damaged or sometimes has fitment issues and will cause these codes, if it check out ok then replace the pedal position sensor, with small chance of it being a bad ECU)

u have 2 faults for the ionization module combined with one for coolant temp sensor, which usually points toward a short or open in the main engine wiring harness, if the wiring harness is inspected ok, then u r looking at replacing the ION module or engine ECU and test the coolant temp sensor.
 

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Discussion Starter #3
Mostly wondering about the readings, maybe they are normal.
I can't see how they are normal, but it's possible they are.

Code P2138 came on a minute after I semi-accidentally sprayed the TMAP sensor because I was trying to spray just the connector 8 inches under the battery with ATF and the car started to idle really rough. I did this to try to prevent corrosion and see if there was a change in my car stalling out sometimes once it was warm/wet when trying to restart it.
Also I read on this forum that P2138 and the TMAP sensor are related.
Definitely a malfunctioning TMAP and/or MAF sensor can make the car idle rough.
Also it seems like all the codes I have been having can come on due to the computer not knowing how much air, pressure and temperature of air that is going into the engine.

Including the injector codes that I had on before and the turbo solenoid.
The only code that is totally mysterious is the coolant temp sensor.
But I left the sensor that is attached to the battery enclosure on the battery enclosure and unplugged (it's not in the car currently). Not sure what it does.

But I did not want to discuss my codes too much, if that is okay.
They are mostly for reference, if some one has a similar problem.
P0201 P0202 P0203 P0204 P0245
P2138 P0325 P2304 P0119 P2123 P2127
 

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A million thing can make the car run rough!! Are u going to check them all ??!!
This how mot to diagnose an issue , and definitely using ATF could've aggravated the issue..
Boost/temp sensor and P2138 are definitely not related, However that connector underneath the battery and P2138 are definitely connected (connector name H24-2)
Again if u had the injectors codes all together, then start by replacing the ECU (no way around it)

second what temp sensor in the battery enclosure u r talking about !!
 

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Discussion Starter #6 (Edited)
second what temp sensor in the battery enclosure u r talking about !!
Never-mind, it's the hood closed sensor, which I already assumed.

I already ordered the TMAP and MAF sensors.
I'll see how the new ones measure.

I'm not really interested in replacing parts on the car until I know that's the problem.
There are many people who have replaced there ECU and other parts on there Saab and it did not fix there problem.
Just about every thread I respond to there are Saab owner's just replacing almost random parts hoping it will fix there problem.
This is not the way I approach car repairs.

Also, you are not doing these people a service telling them they need ECU or whatever.

I took measurements and asked specific questions for a reason, not so I can replace random parts and hope it fixes my problem.
Also I know the codes the car has can be related to the sensors I am replacing, perhaps even all of them.
Even the coolant temp sensor can be related to the MAF sensor P1252 or whatever it was; I no longer have the code, so I did not include it in this listing.
I ONLY INCLUDED THE CODES FOR REFERENCE, I already mentioned I wanted feedback on the measurements not the codes.
This means some one has a problem in the future, they can find out how to approach fixing these problems.
I do this every thread I make or comment on.

I'm about finding the problem, making the repairs, documenting the repairs.
Not telling people to change ECU, then when the ECU swap doesn't help, telling them to do it again or not replying to the thread again.

There's about 10 people involved in this thread:

2 of them switching the ECU did not help.

"Change ECU" is not something that means a whole lot on a forum, no offense.
It might be a guide where to look, but that's about it.
Maybe this might mean something:
"Change ECU -- I have personally worked on 2 dozen Saabs with the following codes "p0201-p0202-p0203-p0204-p0245-p0246" and changing the ECU fixes 90% of those cars".

That might mean something, even though my car has never had code P0246 and I would still surmise from that statement it could be something else.

Also having a bad TMAP and MAF sensor theoretically could throw injector codes and P0245, I would think, since the vehicle does not know how much air is going into the combustion chambers. But I didn't want to get too much into theory in this or any other threads for that matter.
 

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U r not interested in replacing parts until u sure they r bad, but then u already order the sensors without any definitive answer !
Injectors CIRCUIT codes cannot be generated from any other sensor failure no question about it, circuit codes and condition codes are different.
U have a circuit code, u diagnose the circuit which includes the injectors themselves, the wiring and the ECU.
With more than 20 years in the business im not that guy to say i dont do mistake, u give me inputs and i give my feedback based on that, if u say 4 injectors codes to any mechanic nowadays he will just replace the ECU and its 100% fix (unless u visually see the wiring loom is melted and all wires are shorted, then u must be having bigger issues)
Im not gona comment on the voltage measurement of the MAF as nobody can, because its Frequency based sensor, to figure out its working correctly or not u need to measure its frequency by an oscilloscope.
 

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Discussion Starter #8 (Edited)
U r not interested in replacing parts until u sure they r bad, but then u already order the sensors without any definitive answer !
Injectors CIRCUIT codes cannot be generated from any other sensor failure no question about it, circuit codes and condition codes are different.
U have a circuit code, u diagnose the circuit which includes the injectors themselves, the wiring and the ECU.
With more than 20 years in the business im not that guy to say i dont do mistake, u give me inputs and i give my feedback based on that, if u say 4 injectors codes to any mechanic nowadays he will just replace the ECU and its 100% fix (unless u visually see the wiring loom is melted and all wires are shorted, then u must be having bigger issues)
Im not gona comment on the voltage measurement of the MAF as nobody can, because its Frequency based sensor, to figure out its working correctly or not u need to measure its frequency by an oscilloscope.
You're right.
I get it now o_O
I'm going to try the ECU.
Actually would have been way easier if I just started there :LOL:
I'll get back here, when I put it in.
I need an OBDII to USB cable.
Anyone know which one? OR can I buy any one?


This guy:
Uses this one, I think:
 

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Discussion Starter #9
I got the OBDII SX cable and wired it outside the car.
Although I'm not sure if the EM327 would have worked.
Thanks for the help.
Worked, no more extra fuel going into the engine, but I still have a rough idle and also rough 1k RPM to about 2.8k RPM.
Not sure if it is from cleaning throttle body or something else.
Also not sure the MCP upload went perfect (dropped some frames, but completed).
I tried to check MCP version by getting ECU info, but I didn't see if/where it stated which version it was.
I guess I could have checked the MCP version by reading ECU again, just thought of that now.
Runs much better than when it was dumping fuel into the engine like crazy though.
 
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