Heyguys, I am really diggin this forum!
I am an Oldsmobile guy and usually drive Cutlasses when there isn't tons of snow and salt on the road but this year I am driving a VIN W 4wd94 Blazer for the winter. It has been very well maintained by the previous owner and runs excellent, I just recently replaced the fuel pump and intake gasket1k miles ago.

It was-15*Fout yesterdayand I know that will causeproblems with anything but my VIN W 94 Blazer would not start and it usually fires up on the first turn of the key everytime.It would fire on one cylinder every now and then andI smelled gas, it felt like it just wasn't getting enough spark so I replaced the coil since it was giving me problems when it was wet out in the past.

Well that didn't work so I found my code reader and it was throwing a code 23. The code book I have is generic and I am not sure if it is the TPS or MAP sensor.

Wellthetemperature got up to 20*F this morning and it started right up but it was a little rough at first until it warmed up a little. It has a little miss every now and then but it isn't anything to be worried about.
My question is code 23 the MAP sensor or TPS sensor?
I am figuring that since it was so cold outside yesterday the MAP sensor was telling the computer more fueland flooding the engine but I am not sure if that would cause some misfiring. Before this problem occured the Check Engine Light would come on once the engine heated up and went into closed loop, but I never pulled the codes. I am assuming the code would still be in the memory and it was the code 23 I am getting today.

If it isn't the MAP sensor or TPS that would give me these problems when it's ***** cold out to hammer a nail into a piece of wood with a Bananna, would it be the fuel pressure regulator that is starting to go?

 

Found this:

http://www.troublecodes.net/GM/94-95_43W.shtml

You guys should post this in the Tech Articles:

23 - Inlet air temperature sensor signal showed an air temperature of -29*F for 4 seconds.


*EDIT by swartlkk* - Removed copied OBD1 trouble codes due to length. The link is sufficient to direct others. Pertinent trouble codes were left.

 

get a pressure gauge and put it on it to verify or deny any issues. As you probably know, these engines are prone to regulator/injector issues. So...to be sure a fuel pressure test/ leakdown is in order. Jerry A fuel pressure tester-cheap to buy-good to have!(if you don't already)[&o]

 

It's running fine now, what would cause it to not run at all when it's below zero?
Is it a bad MAT sensor?
I was just told by the previous owner the fuel pressure regulator was changed not too long ago.

 

Just for S@#%^'s and giggles-next time it gets that cold make sure to put a can of Dry Gas in. It could be something as simple as that-just a thought...Jerry[&:]

 

What is Dry Gas? Do you think its a problem with water in the fuel?
Also, the computer keeps throwing the code 23 for the MAT sensor after clearing the codes.
Where is this sensor located and would it cause the problem with not starting with temperatures below 0*F?

 

Code 23 has nothing to do with the MAP sensor or the TPS sensor.

 

ethanol will freeze mine did the other day i don't run that crap when it is cold

 

that's why you use isopropyl. Jerry[:@]

 

Pure ethanol freezes at -114 degrees C (-173.2 degrees Fahrenheit) so given normal winter temperatures, ethanol is not the cause of fuel freezing. Now, if there is excessive water in the fuel...