I am FREEZING in my car in winter especially

[Mechanical Mike]

I'm with Bill, get an ohmeter on the coolant temperature sensor & compare the reading to the chart he posted. Try to check it at the same temperature as when you're having the starting problem. For an intial check I'd just check the sensor while it's in the engine & the engine is cold.

If I did my math correctly then -21 Celius is -6 Fahrenheit. I wouldn't expect 5w-30 oil to give you any problems at that temp.

While you have the ohm meter check the resistance of the ignition coils. Here's a Techinfo article on checking the coils. http://www.pontiacbonnevilleclub.com/fo ... =48&t=1683

[laimisl]

Thank you all,

I see I have big project to go through, remember I park outside, so it is tough to do it fast as it is very cold outside.

I have cleaned TB body about a year ago.

I will let you know what readings did I get etc.

Have a nice weekend.

FYI I have owned this vehicle since May 2003, biggest repair done was intake manifolds replacement.

It is a solid car, so I will try to make it running for quite a while I hope.

Cheers,
Larry

[laimisl]

I did not have a chance to do any of the testing yet, but I remembered the following,

even in warmer weather when starting the car quite often my revs when just fresh started my revs were jumping from 500 to 1200 back and forth for some seconds until it would rev up for up to 2k or more and then all reached equilibrium.

Do you think it has something to do with the problem with very cold starting at cold temps?
Any similar experiences?

Thanks,
Larry

[bill buttermore]

My '95 FSM lists the following items under "...unstable idle..." the definition of which includes: "...Engine idle speed may vary in RPM..."

Items that also are included under "Hard Start" are highlighted in orange.

Vacuum leaks
PCM grounds (powertrain control module ( computer))
Injector balance
Fuel in Pressure Regulator hose
Evaporative Emission Control
O2 sensor
Ignition system; plugs, wires, etc
Cylinder compression
Worn camshaft, weak valve springs
Sticking or binding throttle
EGR system
IAC
A/C signal to PCM
PCV
PROM updates
Broken motor mounts
Generator output voltage should be >9, <17 volts
Binding or out of adjust cruise control cable

I would suggest you check the temperature sensors, and the throttle position sensor first, then move on to cleaning the IAC valve and passages, then the other items in orange.

[laimisl]

I am going to check ECM and primary and secondary coils there. Question should I lubricate them with dielectric of some sort or not?

Thanks,

Larry

[laimisl]

Sorry I meant ICM not ECM.

So do I need to lube it with dielectric grease or not.

Thanks,
Larry

[Archon]

It's a good idea to put the silicon grease on the posts, and wouldn't hurt to do the same for the primaries.

[laimisl]

Good day this sunny and still cold Sunday,

Temp reading outside is -10C=14F.

So I got the scanner and the meter for volts and ohms etc.

First I have scanned vehicle with the CAN OBID II, and guess what, no DTC found.

This is what the reading was from scanner when car was not running:

LIFE DATA:
Fuel Sys 1 - OL not ready CL
Fuel Sys 2 - OL not ready CL
ST FTRN 1 - % - 0
LT FTRN 1 - % - 9.3
MAP (in.hg) - 10.3
Coolant temp in the scanner from coolant sensor was the same as by the exterior temperature meter = 14F

MIL - OFF
DTC - 00
Reading Complete - Y
Freeze data exists - N

I/M STATUS:
MIL Status - OFF
Misfire Monitor - OK
Fuel syst monitor OK
Comp component- OK
Catalyst Mon - N/A
Htd Catalyst - N/A
Evap System Non - OK
Sec Air Syst - N/A
A/C refrig mon - N/A
Oxygen Sensor Mon - OK
Sens HTR - OK
EGR syst - OK

When I have started the engine the same way very hard and it took very many turns to start and fire up the engine,
the scanner shower following:

LIFE DATA:
Fuel Sys 1 - OLCL using HO2S
Fuel Sys 2 - OLCL using HO2S
ST FTRN 1 - % - 1.5
LT FTRN 1 - % - 14.8
MAP (in.hg) - 11.2
Engine RPM - 981
Speed - 0
IGN APV DEG - 11.0
IAT - 23F
MAF (lb/min) - 0
ABS LT TPS % - 0
O2S11 V=from 0.125 to 0.8 and % from -2.3 to 0
O2S12 V=from 0.27 to 0.5 and % N/A
OBD2 Stat - OD22 - CALIF

Coolant temp was rising as the engine continued to work, went up to 153F and on.

MIL - OFF
DTC - 00
Reading Complete - Y
Freeze data exists - N

I/M STATUS:
same like I have seen when the engine was not running.

So then I went to the indoor garage and tested the ignition wire secondaries, otherwise called ICM secondaries as one of you my friends have suggested, all had nice reading of 5.9 mOHM or kOHM (the meter was set to 200k setting in OHM section as in your picture).

Unfortunately I did not have the right socket to unscrew the IC modules as what I had was few sockets in metric, and ICM screws are probably in Imperial inch system.

Then I have decided to rescan the vehicle and it gave me these different parameters then before:
LIFE DATA:
ST FTRN 1 - % - 3.8
LT FTRN 1 - % - 3.8

I/M STATUS:
MIL Status - ON
Evap System Non - INC
Oxygen Sensor Mon - INC
Sens HTR - INC
EGR syst - INC

QUESTION, what means INC, INCluded, or INCorrect?

Then I have tried to remeasure TPS sensor (on the 3 pins combination a with b, b with c, and a with c) if it gives me readings of .2 and .74 volt when throttle is closed at 0%, it gave me no reading, then I tried the same with ignition on and no reading again, I thought maybe there is something wrong with how I do it, and nothing again, just 0.

Then I tried to measure the same on MAF on the 3 pins combination (a with b, b with c, and a with c) and it gave me reading of 0.01 to 0.02V.

So then at the same time I also cleaned the battery connections and lubed them with dielectric lube.

After all was completed I started the engine (of course now in warm environment and after it has been started and warm it turned on from half a turn) and I got CHECK ENGINE on!

I have scanned and it told me this: "P0122 generic TPS/Pedal sensor A Circuit Low Input"

So I have checked if I have connected the sensor ok. It was connected ok.

I have tried to disconnect it and see how the car starts then. To tell you the truth while TPS disconnected it started like every time, not very nice, revs jumping - 950 RPM plus or minus 150 RPM for a moment of 15 seconds, after which it evened out.

After I have reconnected TPS the code and CHECK ENGINE was gone, no more error was detected by scanner.

So my thought is: the TPS is giving faulty readings especially when cold.

Please advise if you think the same, and if from above you could have more insight then me.

Thanks,
Larry

[bill buttermore]

My old Chilton's gives the procedure for testing the TPS, but, as I am not the sharpest knife in the drawer when it comes to electrical diagnostic techniques, I have requested some help for you from smarter people.

[clm2112]

You have the scan tool, so plug in, set it to watch the TPS value, and move the throttle blades slowly by hand. Watch the TPS value change. It should increase value soothly as the throttle opens. If it jumps around then you have a bad one. If you can't get a reading from it at all, disconnect it and check wiring.

TPS is a dirt simple device. It's a linear potentiometer (like a volume knob on a radio) with three wires. One wire is the sensor ground (ties to all of the other sensor ground wires.) Another wire is the reference voltage provided by the ECM, it should remain constant while the ignition system is powered up. The last wire is the signal that varies as the TPS sensor is moved. You can also check the sensor by uplugging it and using a voltmeter on the resistance setting, check the three pins in pairs. One pair (the ground and reference voltage pins) will show a constant resistance at all throttle settings. Either other pair will show a variable resistance as the throttle is moved. Look for any infinate resistance values popping up while moving the TPS by hand (gaps or corrosion inside the TPS sensor.)

You can also use the voltmeter to watch the signal wire with the ignition system powered up (engine does not have to be running.) It will vary with the throttle between ground and the reference voltage (i.e. between 0VDC and +5VDC.) Typically the TPS is adjusted to put out +1 VDC with the throttle closed. Voltage on the signal wire will increase in proportion to the amount the throttle is opened.

[laimisl]

Thanks clm2112,

You wrote:
"One wire is the sensor ground (ties to all of the other sensor ground wires.)
Another wire is the reference voltage provided by the ECM, it should remain constant while the ignition system is powered up. The last wire is the signal that varies as the TPS sensor is moved."

So I understand you refer to the wires that arrive at the TPS so I would check the 3 pins and their readings? SOrry for asking this, just never did that before and want to be sure I got the instructions correctly. Thanks.

Also you wrote: "You can also check the sensor by uplugging it and using a voltmeter on the resistance setting, check the three pins in pairs." So her am I checking OHMs? - that is resistance right?

You wrote: "One pair (the ground and reference voltage pins) will show a constant resistance at all throttle settings." Do you mean I have to use ground from the car body-frame, or that is the first pin?

Thanks,
Larry


PS: your below Latin adage is very interesting: "Si vis pacem, para bellum" - "If you wish for peace, prepare for war", you in army?

[clm2112]

So I understand you refer to the wires that arrive at the TPS so I would check the 3 pins and their readings? SOrry for asking this, just never did that before and want to be sure I got the instructions correctly. Thanks.

Once you find which one of the three pins is the ground wire, then you can use that pin while checking the other two wires. Typically the ground wire is black, the reference voltage wire is white. The signal wire can be any color, though grey is a typical color choice from GM.

The quote is just my own words to live by...hope for the best, prepare for the worst.

[bill buttermore]

Thanks, Curt.

[laimisl]

Good day All,

Today it is -21C=-5.8F and I could not start, it turned well, but not enough to crank it up as at this point it requires to turn it so well (just like turning the engine of the old tractor) and there was not enough power in this cold temp.

So I had to get the ride from my colleague.

Tonight, they promise 6.8F (-14C) so if I have time and luck to start it I will test the volts and ohms of the TPS in the inside garage again.

Question: could I test the wire that comes to the TPS? for volts or whatever, so I can see that the wire is ok and sends the right signal, what are the # of volts or ohms to expect there per each pair?

Thanks,

Larry

[clm2112]

Take a close look at the connector on the TPS. Moulded into it is three Letters "A", "B", and "C"...one for each contact in the connector. The actual voltages used by GM over the years have remained constant, even if the connector and physical look of the TPS sensor have changed.

For the older cars, like mine, the connector is flat with all three pins lined up in a row. "A" is the ground, "B" is the output signal to the ECM, "C" is the +5 VDC reference from the car's computer. The signal on pin "B" varies from approximately 0.5 VDC with the throttle closed to about 4.5VDC with the throttle wide open. (These are approximate voltages...each TPS sensor can be a little different, that's why they are adjustable.)

Newer cars have a round connector with the same "A","B", and "C" pins in a circle. The pins for ground and reference voltage are reversed, but the signal is still coming out on pin "B" and the levels are the same as the older cars.

So, take your volt meter, set it on the DC scale, and measure across pins "A" and "C" with the ignition on. You should see about 4.5 VDC to 5.0 VDC on the meter. That confirms the ECM of the car is putting out the 5 Volt reference voltage for the sensors to use. Now, take a look at the voltage on pin "B". With the throttle closed, it should be 0.5 VDC to 1.0 VDC. Open the throttle by hand slowly...watch the voltage increase till the blades are fully open and it should be around the same voltage as you saw when testing for the reference voltage.

It help to take a pair of needles and pierce the insulation on the wires, giving you a place to hook the meter up.

[Mechanical Mike]

The easiest way to check the TPS is with your scanner. Most scanners will show TPS voltage & it should range from about .4 volts with the throttle closed to just over 4 volts with the throttle wide open. The only reading that should make a difference at start up would be the .4 volts with throttle closed.

Did we have you try starting with the MAF (mass air flow) sensor unplugged?

You showed this for one of the long term fuel trims -"LT FTRN 1 - % - 14.8"
I'm not sure if that is 'dash 14.8' or 'minus 14.8'. If that's just a dash & the reading is +14.8 then you may have a vacuum leak.

[laimisl]

Thank you,

I will try to do these tests tonight if I will be lucky to start it up and to move it in the garage temporarily for the testing.

As for the long term fuel trims -"LT FTRN 1 - % - 14.8", as you see with engine off and top cold it measured 9.3, then with engine on 14.8, and then in the garage 3.8.

ST measured 0, then 1.5, and then 3.8 accordingly.

Do you see bad pattern here.

Where to search for these vacuum leaks and what spray to use to find it?

I will revert with my findings on the TPS measurements.

Thanks,
Larry

[laimisl]

Regarding vacuum leak, I remember there is a loud air suction sound at the front right fender.

Also under the fender there is a little reservoir that has a hose disconnected, and it looks like in there there is just the air, no fluids, what is that thing there under the fender?

Could it be it?

Larry

[laimisl]

Can I use brake disc cleaner to search for vacuum leaks, or that is flammable?

L.

[laimisl]

I am just about to go out to test it all. Any additional suggestions before I leave?

Larry