97 Intrepid Cold Start Problems Help!!

[willy72]

I have a 1997 Intrepid with the 3.5L engine. This car actually runs great during normal weather. For the past three years I have had problems in cold weather. When the temperature reaches single didgets, the car simply won't start. It turns over and attempts to fire, but just will not start up. I have had this car on the diagnostic machine the last two years and of course they can't find anything wrong. The only solution I have now is to keep it in the garage and fire up the torpedo heater to warm up the temperature. It will then fire up and run eventually.

Has anyone had any similar issues? Could you please offer some advice? I have been told that a coolant sensor would have been picked up on the diagnostic machine and currently one of the mechanics is trying to talk me into replacing the coil packs. Please help.

Thanks,

Bill

[A. Souphound]

Bill,
Have you checked the Battery voltage while cranking the engine? If you put a voltmeter across the battery you must have at least 9 volts while cranking.
Alvin

[willy72]

The battery voltage is good. Actually the battery is almost new and cranks over at a good rate. It just doesn't seem to fire consecutively enough to start running by itself.

[mparks48]

I have a 95 3.5 ES Intrepid thats had the same problem for the past 5 years. If I wait 2 to 3 days the car will usually start. The Dodge dealership has not been able to find the problem. Between me and the dealership we've replaced almost every sensor on the car. As I write it, sets in the front drive way and won't start. Temperature got down to a -3 chill factor last night. Turns over good, good spark, smell gas, but no start. Good thing I've got another car to drive.

[A. Souphound]

You say the battery voltage is good.... is it at least 12.6V after you cranked the engine for approx. 15 seconds? What is the voltmeter reading when you are cranking the engine i.e. voltage drop? The fuel injection system and the ignition needs a minimum of 9 volts to operate properly. The battery is the place to start your diagnosis. If the battery meets or exceeds the ampere hour rating requirements for the car, and the voltage during cranking is above 9V then, you can move on to the next step. Since the problem only occurs during 'cold weather' have you an idea what the temperature reading would be when the problem occurs? You know the efficiency of the battery decreases as the temperature gets colder.
Alvin

[A. Souphound]

mparks48 & Willy72:
I'm intrigued by this problem! I understand neither of your batteries are dead, but have either of you tried to start your car using an additional battery and jumper cables? mparks48: You gave a wind chill factor of -3 F, what was the ambient temp? around 10F? It would also help if I knew the ampere rating of your batteries.
Alvin

[mparks48]

Alvin

The battery in my Intrepid is heavy duty and was purchased last summer. Too cold to go out and check it right now but will check the actual ampere rating tomorrow. I believe it's between 7 an 8 hundred cca's. Will also check to see if there are any engine codes being flashed by the diagnostic system on the car. The problem occurs when there is a hard freeze. A slight frosting over night usually does not keep it from starting. The -3 F was a chill factor. The ambient teampture was around 13 F.
I believe this is the same problem Bill is having and is most likely coman to the 94 to 97 Intrepids. One possible cause could be one of the many
sensors (in freezing temperture) is falsely signaling the PCM module not to start. Just a guess on my part.

Mark

[willy72]

I'll check tomorrow after work. I'll post around 7:00pm or so and get the detailed information you have requested.

Thanks much, Bill

[LHSDriver01]

Don't know if it's been tried yet or not...

Change the spark plugs, to champion coppers, part #R12LYC, and gap to .035. Change the wires if it's been a while. Also change oil to a 5w-30

mparks48:
What is the date of manufacter for your 95'? There is a TSB detailing a PCM update for cold weather starting problems on 1995 models built before feb of 95. something your dealer may have overlooked.

I had a 95' that was built nov. of 94. Car would not start under 32F. Changed the plugs and wires, and it fired like a champ every morning.

[coalminer]

I have seen this problem before and when I replaced the tempertature sensor for the engine computer the car started ok. Try to unplug the temperature sensor when it is cold like that and see what happens.

I have a 95 Acclaim that is doing the same thing, but I can get it started with lots of cranking and holding the pedal on the floor, but I have not had a chance to get the sensor for it.

[A. Souphound]

[quote=mparks48]Alvin
Mark,
The purpose and function of the Air Temperature Sensor and the Coolant Temperature Sensor is to modify the air/fuel mixture. Signals from both Sensors are superimposed on each other back to the PCM. The PCM then controls the mixture and idle speed while the engine is warming up.
If there is a malfunction in either of the two sensor/s or their circuits, would result in an incorrect voltage being sent to the PCM, and an incorrect air/fuel mixture (too rich or lean) to the engine. Both Sensors have MORE resistance in cold temperatures resulting in less voltage being transmitted to the PCM. The Sensors operation can be checked with an Ohm meter by reading and comparing resistance at cold and warm temperatures.
I just read Coalminer's message, and I believe it bares out this theory.
Alvin

[mparks48]

LHSDriver01
I believe the sparkplugs could be the problem. I read on the internet that this was a in a service bulletin put out by chrysler. Tried to pick up a set today however the 2 auto parts stores that are close by, did not have them. Will call around tomorrow for the Champion Gold R12LYC.
Frustrating because the plugs in the engine are Bosh Platium +4's. Just
doesn't make sense to me how the plugs could keep it from starting.
I'll also check on the PCM update. The car was built January 95.

Alvin and coalminer,

If the spark plugs don't work then I will check/change out both the air and coolant sensors-one at a time- to see which one may fix the problem. Hopefully, by Thursday I'll be able to tell Bill what the fix action will be. If he doesn't beat me to it. Alvin the battery is a Champion heavy duty with 950 amps and 770 cca's.

Anyway, I appreciate all the inputs and will let you know by Thrusday if
they worked.

Thanks,

Mark

[mparks48]

Bad weather and one week vacation delayed spark plug change out.
So the good weather on New Years day gave me a chance to install standard Champion R12LYC plugs. The car started with no problem, however the temperature was around 60F. Guess the only thing to do is wait for cold weather.

NAPA carriers both the air ($28) and coolant ($24) sensors and the plan will be to replace them one at a time if the spark plug change out doesn’t work. Will post an update after our next extreme cold day.

[A. Souphound]

Originally Posted by mparks48

Bad weather and one week vacation delayed spark plug change out.
So the good weather on New Years day gave me a chance to install standard Champion R12LYC plugs. The car started with no problem, however the temperature was around 60F. Guess the only thing to do is wait for cold weather.

NAPA carriers both the air ($28) and coolant ($24) sensors and the plan will be to replace them one at a time if the spark plug change out doesn’t work. Will post an update after our next extreme cold day.

Mark:
If you have a VOM you can check resistance/voltage to determine if the sensor/s are operating. I'd be glad to walk you through the procedure if you want to.
Alvin

[budc]

Originally Posted by A. Souphound

Mark:
If you have a VOM you can check resistance/voltage to determine if the sensor/s are operating. I'd be glad to walk you through the procedure if you want to.
Alvin

Hi Alvin,
I'm having similar problems with my daughters 95 intrepid. Just changed the battery. Pulled one plug and found it fouled with gas.

Could you tell me where the water and air temperature sensors are?

Thanks.