checking OBD II codes... dumb question

RustX7 · #1 02-20-2007, 05:17 AM

Up til now I haven't tried serious work on a car that's newer than 1988, so OBD II codes are new to me. This might be a dumb question... sorry if it is... but is there any way to pull the code from an 01 lesabre without a code scanner? I've probed the four pins of the connector that actually have a pin in them and one of them is fluctuating around between .35v and .65v or so.

Yeah, I know it's a long shot, but I had to ask.

If it's not possible, what code scanner do you guys recommend buying? I tried getting a guy at autozone to pull the code with their cheap actron scanner but either he wasn't using it right or it was too cheap to identify the code... and yes, my "Service Engine Soon" light is on.. not the "Service Vehicle Soon" light.

The temp has been running at about 145 for a while as opposed to 150 (I think that was it anyway, whatever temp is dead center on the analog meter.) Could this be the thermostat stuck open? Also the ABS light is on, I think because of a bad or dirty sensor on the front right wheel.

I welcome any suggestions. Thanks for your input.

Bassasasin · #2 02-20-2007, 08:27 AM

Temp should be 180...
ABS wont read with a code reader.. has to be a ABS diagnostic tool or sometimes get lucky by probing the ABS connector depending on the failure, usually a wheel sensor either intermittent or circuit open.

Dont think you can read the codes for a 01' without a code reader.. I think that changed when they went from OBDI to OBDII... 94' ish.

Good Luck

Smith1000 · #3 02-20-2007, 07:48 PM

Temp may be okay. Dead center on the analog sounds like it could be where it is supposed to be. I have a 97, not an '01, so I don't know for sure. How's the heat when cranked on running fully warm? Is it fairly hot? If a vehicle is running cold, it usually really hurts the gas mileage too. If it is running cold, thermostat would be my first guess. I probably would check the coolant level too.

The OBD II reader I have is a $40 one from Harbor Freight Tools. Seems to work okay. Some of the other auto parts stores will read codes too. O'Reilly does around here.

RustX7 · #4 02-21-2007, 01:50 PM

The heat is pretty pathetic. I mean, it works, don't get me wrong, but it's nowhere near what you hope for as far as good heat, and I think it got that way when the temp decided to be lower one day. Gas mileage seems to be fairly consistent.

Temp USED to be always dead center on the analog gauge, but now it's always one click to the left of dead center. I will check the coolant level.

Smith1000 · #5 02-21-2007, 08:51 PM

In my 97, it always seems like it kicks out more heat if I run it on vent with the heat setting well in the red. Usually have to back it off. If I leave the heat setting in the same position and click it over to heater or combo heat/defrost, it always seems cooler. It has been down to 1 or 2 degrees here in the mornings and it provides plenty of heat. I have to bump it further to the right, in the red, when cruising down the highway though to keep the heat at the right level. I have a 190 degree thermostat in it and it reads 180 or less when driving, but I don't know how accurate the reading is. It does climb up some at idle. The car has a extremely large radiator in it.

Bassasasin · #6 02-21-2007, 10:13 PM

Heat is directly comming from engine coolant circulation in the heat exchanger and the and not the radiator. The thermostat adds cooler coolant to the system to manage the engine coolant temperature.
If the heat exchanger is blocked externally or internally or controlled by a vent valve, without air flow theres no transer of heat to the interior.
If the thermostat is stuck open or not sealing it will cause it not to warm up quickly and not reach its target temperature at the sensor.

I have noticed that a thermostat more often operates in pulses the cooler the environment realatively quickly opening when the temp is reached and closing quicker when the cold coolant enters the engine side of the system.
The temp guages dont show the pulsing but sometimes you can look closely on some guages and see it change a bit.

Bass

RustX7 · #7 02-22-2007, 12:19 AM

According to the digital readout, the temp is always around 145 now (I think I'm remembering correctly.) This is with the analog meter one click to the left of the center. I'm not sure what the digital readout was when it was at dead center on the analog. Seems low to me anyhow.

RustX7 · #8 02-22-2007, 12:19 AM

According to the digital readout, the temp is always around 145 now (I think I'm remembering correctly.) This is with the analog meter one click to the left of the center. I'm not sure what the digital readout was when it was at dead center on the analog. Seems low to me anyhow.

Smith1000 · #9 02-22-2007, 06:39 AM

Yes, that thermostat really has to stay mostly closed in these cold temps to get the car warm. The large radiator really keeps antifreeze cool.

I have a little Nissan truck that the thermostat will not close to allow the truck to warm up without cardboard partially blocking the radiator (in the winter). With the cardboard, it will build enough heat to close it down. Otherwise, the heat in the cab is poor and the gas mileage is poor. I replaced the thermostat once and it helped some, but still runs fairly cool.

I have not seen one with a digital read out. Could be the temp sensor is bad if it is reading 145 degrees. It could need a new thermostat if it is really only running at about 145. I

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