97 Intrepid Cold Start Problems Help!!

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

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

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.

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.

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

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

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

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

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.

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.

[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

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

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.

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

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.

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.
BudC:
The (ECT) Coolant Temp. Sensor on both the 3.3L & 3.5L are near the Thermostat housing. (Where the top radiator hose attaches to the engine). *Should have a tan/black (+) and a black/blue (-) wires attached.

The (ITS) Intake Air Temperature Sensor/s: 3.3L engine: Mounted in the back of the intake manifold near firewall centerline.
3.5 Engine: Mounted in the intake manifold. You will have to remove the plenum. *Should have a black/red (+) and black/blue (-) wires attached.
*Note wire color code given to help identify sensor/s.
**Same offer I made to Mark stands if you want to check the sensor/s voltage/resistance.

Alvin.

I'm having the same problem with a 95 Intrpeid.

After sitting for a day or 2, or during cold weather, it would have to turn over for 20-30 seconds. During that time, it would fire once, but not start. Finally it wouldn't start at all and I had it towed to the mechanic.

Since then, I've had the plugs and wires, ignition coil, and O2 Sensor replaced.

It's been narrowed down to something that is causing the fuel injectors to open for 200ms, instead of the 4ms that it should.

The tricky part is, is that it's not repeatable. Sometimes it will fire and start before I can even release the key. I can try it 10, 30, minutes later, and it won't start.

Any idea what could be causing this?

Thanks,

Chris

Thanks Alvin,
I found the cold sensor next to the thermostat
(I think) and have the same question as Budc.
Where is the air sensor? I have a digital fluke
meter and will check them at your direction.
However, I'm guessing that I'll only get a bad
reading if the weather is cold and the car wont
start.

Bill,
Did you have any luck with your starting problem?

Mark

Thanks Alvin,
I found the cold sensor next to the thermostat
(I think) and have the same question as Budc.
Where is the air sensor? I have a digital fluke
meter and will check them at your direction.
However, I'm guessing that I'll only get a bad
reading if the weather is cold and the car wont
start.

Bill,
Did you have any luck with your starting problem?

Mark

Mark:
See my answer to BudC. I gave the location of the ITS (Air Temp. Sensor) for both 3.3. & 3.5L. No, it doesn't have to be cold to find a bad sensor.
To check the ECT (Engine coolant temperature) Sensor:
a. With the engine completely cold, remove the connector from the sensor. You will see two pins (terminals) inside the sensor. Check the resistance between the two pins with your VOM. If ambient temperature is around 50F the reading should be approx. 16 - 18K ohms.

b. Start the engine and let it warm up until it reaches operating temperature. (170 -200F) Check the resistance again, the resistance should be lower, between 600 - 900 ohms.

c. Stop the engine. Turn the key "ON" and check the VOLTAGE in the sensor connector by placing the voltmeter on the tan/black (+) terminal and the (-) probe on the blue/black wire terminal. It should read approximately 5.0 volts.
Let me know your results.
Alvin

Mark, Bud, Willy, and All:
CHECKING THE INTAKE AIR TEMPERATURE SENSOR:
The procedure is almost the same as the I described for checking the ECT.
a. With the engine completely cold, remove the connector from the sensor. You will see two pins (terminals) inside the sensor. Check the resistance between the two terminals with your VOM. With ambient temperature approx. 50F, resistance should read approx. 8K ohms. *If temperature is lower, resistance will increase and vice versa).
b. Start the engine and let it warm up to operating temperature (170-200F). Check the resistance again it should be lower, approx. 170 - 20 ohms.
c. Stop the engine. Turn the key "ON" (engine not running) and check the VOLTAGE at the harness connector. Voltage should be approx. 5.0 volts. If the sensor resistance results are incorrect, I would replace the sensor.
Alvin

Alvin,

The cold sensor test good. Took leave this Friday and will check the air temperature sensor then. The problem is getting the car to cool down during the week. By the time it does it's past my bed time.

Thanks,

Mark

Alvin,
I believe the air temperature sensor is bad. I get 20k ohms resistance cold vice 16-18k and I'm reading 3.1K ohms resistance vice 600 to 900 ohms hot. 5V check OK. Tempertature was right at 50 degrees F.
Got the part on order and plan to change it out tomorrow. After that, guess we got to wait for a real cold day to see if it will start. Of course that cold day can take it's time coming. Will post an update then. Thanks again Mark

Mark,
Just for clarification: The Intake Air Temp 'hot' resistance reading should have been in the approx. range of 170-20 ohms, and you read 3.1K ohms.
Agreed, sensor should be replaced.
You should see better drivability even in the warmer temperature as the PCM will be calling for a leaner mixture (at runniing temp.) with the new Sensor. I will be watching for your up-date. I agree on the nice weather, it can stay like this till April and then warm up, as far as I'm concerned.
Alvin

Alvin and all,

This morning the temperature droped to 10 F and my 95 3.5L ES Intrepid would not start. Turned over good but no cigar. This afternoon I got it started by holding the gas pedal in slightly and cranking on it for about 15 to 30 seconds (20 F). Drove it around the block and noticed that the check engine light stayed on. A diagnostics check revaled codes 51, 23, and 22. Both the cold and air sensors are indicated as possible problems and I plan to check them again on Thursday. Also, added a can of dry gas to the fuel tank, just in case there is a gas freezing problem. Will try again in the morning to see if she will start.

PS. Check engine light went out and did not come back on durning sometime while I was checking the engine codes.

Alvin and all,

This morning the temperature droped to 10 F and my 95 3.5L ES Intrepid would not start. Turned over good but no cigar. This afternoon I got it started by holding the gas pedal in slightly and cranking on it for about 15 to 30 seconds (20 F). Drove it around the block and noticed that the check engine light stayed on. A diagnostics check revaled codes 51, 23, and 22. Both the cold and air sensors are indicated as possible problems and I plan to check them again on Thursday. Also, added a can of dry gas to the fuel tank, just in case there is a gas freezing problem. Will try again in the morning to see if she will start.

PS. Check engine light went out and did not come back on durning sometime while I was checking the engine codes.

Mark,
Remove the (-) battery cable for a minute or so, to clear the codes.
The symptoms indicate a 'lean' mixture which you over came by holding the gas pedal in slightly increasing the voltage from the TPS (Throttle position sensor located on the throttle body) and in turn called for a richer mixture.
If you would like to check the TPS: It's much the same as the others:
a. Disconnect the TPS electrical connector. VOM/DMM (+) lead to purple/white wire, (-) lead to black/blue, Key 'On' check reference voltage from PCM should be 5V.
b. Reconnect the connector to the TPS. (+) probe to orange/blue terminal, and (-) probe to ground. With the throttle closed voltage should read 0.5 - 1.0V.
c. Slowly open the throttle and watch the voltage increase to a wide open throttle reading of 3.5 -5V. The transition from low to high voltage should be smooth.
Alvin

Alvin,
The Intrepid started the following morning (Wednesday) with no problem. The temperature was 15 F. Today I cleared the codes and checked
the TPS sensor as you sugested and it checked
good. I also checked the cold sensor. At
20 to 25 degrees F the resistance was 28K
ohms and when warmed up it change to
about 750 ohms. The car started with no
problem. I attributed the high cold resistance
to colder temperature. I noticed looking at a
schematic drawing of the electrical system
that the tps, ox, coolant and air sensors are
routed through relays (1,3,&5). I'm wondering
if one of the realys might be freezing up in extreme
cold weather. The wiring diagram I've got is not
specific as to which sensor goes through which relay. So I have no idea as to which relay might be causing the problem. Does that sound plausible to you or do you think I'm out in left field?

Mark

[QUOTE=mparks48]Alvin,
The Intrepid started the following morning (Wednesday) with no problem. The temperature was 15 F. Today I cleared the codes and checked
the TPS sensor as you sugested and it checked
good. I noticed looking at a
schematic drawing of the electrical system
that the tps, ox, coolant and air sensors are
routed through relays (1,3,&5). I'm wondering
if one of the realys might be freezing up in extreme
cold weather. The wiring diagram I've got is not
specific as to which sensor goes through which relay. So I have no idea as to which relay might be causing the problem. Does that sound plausible to you or do you think I'm out in left field?

Mark,
Glad to hear your car started, and the TPS checked out O.K.
You said "I also checked the cold sensor. At
20 to 25 degrees F the resistance was 28K
ohms and when warmed up it change to
about 750 ohms. The car started with no
problem. I attributed the high cold resistance
to colder temperature."
Your understanding of Temperature versus Resistance in this sensor is right on!
I failed to see the relays you are speaking of, but I'm not blessed with the greatest diagrams either. You said you cleared the codes, have you had any more 'check eng' indications since then, and how is the driveablilty of the car?
Alvin

Alvin,
THe intrepid started today (Sunday) with no problem (17 degrees F chill factor 10 degrees F). No check engine light or any other indication of problems. I'll have a chance to start it up tomorrow morning at 5AM an it will be even colder then today. Will see what happens. The engine seems to run smother since the air sensor was replaced. I noticed it most when stopped at a light (in drive).

Mark

I am having it sounds like the exact same problems as Mark!
I have had 2 o2 sensors replaced as well as plugs and plug wires.
I gave the air sensor info to our mechanic as I am sure these were not things that were checked. I hope this is it! Mark- did you car give you trouble going up hills or sitting in drive at intersections?

Mark-
What all sensors did you replace?

95iceintrepid,
I had no problems going up hills. It did however idle a little rough stopped at an intersection in drive. That problem seems to have cleared up after changing out the air sensor.
ALvin,
The intrepid started on Monday and the temperature was 7 degrees F. It was 3 degrees colder then when it wouldn't start last week. There's still something not quite right however this is a whole lot better than guaranteed not to start at 20 degrees or below. Solution so far was to change the sparkplugs and air sensor. I believe there's a third factor and I'll still be looking for it.
Mark

Mark,
I did find some info on another site that noted there was a pcm update put out by Dodge for cold starts. It included new plugs, and a software update . Did you see it?

95iceintrepid,

95iceintrepid,
I'm aware of the software update and I'm not sure if mine has been updated. I think there is also a new safty recall out and the 95 intrepid is included on that recall. I plan on getting both looked at the next time I have time to take it to the dealership.
Mark

Mark,
I got mine back last nite it was sitting at my mechanic for a week, I did not have any work done except when I got it home I put the Champion spark plugs in and changed the oil to 5w30. The temp lastnite was -1°. I started up like crazy this AM. I am not getting too excited though. Give it a few days. I do plan to see a dealer about the PCM.
The rough idle you spoke of:I had the same problem in drive at intersections. But today it did not do it at all. The plugs I took out were not the ones reccomended by the TSB for cold starts neither was the gapping correct. I can not believe this would solve my problem.... We will see. I plan on getting the recall done too. Keep me posted on your car. It sounds like you have mine!!

i changed my fuel pump it fix t it right up