1994 Dodge Grand Caravan 3.3L - Where is the Air Charge Temp Sensor? (Cold Stalling)
#1
09-25-2011, 03:37 PM
Join Date: Sep 2011
Posts: 15
Likes: 0
Received 0 Likes
on
0 Posts
1994 Dodge Grand Caravan 3.3L - Where is the Air Charge Temp Sensor? (Cold Stalling)
Here's my question: On my 1994 Dodge Grand Caravan LE, 2WD, 3.3L engine I cannot find the Air Charge Temperature Sensor (also known as the Intake Air Temp Sensor). So...where is it? Or does my car not actually have one?
Background:
My car is cold start stalling. That is, it starts up great, runs great for the first mile, but once it starts warming a bit I get hesitation during acceleration and stalling at idle. Once it reaches normal operating temperature, it runs great again. I think that this means the air temp sensor is failing. But I can't find it! It's not on my Chilton Manual wiring diagram. It's not on the intake hose. I can't find it on the intake manifold. I looked all through the manual and all over the internet.
Originally it was stalling while driving at speed. So, stuff already done:
1. Replaced camshaft sensor
2. Replaced crankshaft sensor (after these two, it only stalled at stops)
3. Replaced Fuel Filter
4. Replaced Idle Air Control Motor
5. Cleaned out Throttle Body
6. Replaced Spark Plugs
7. Replaced Spark Plug Wires
8. Found and repaired vacuum leaks
9. Replaced EGR Valve. (after this, I noticed that it only stalled during warm up)
10. Replaced Engine Coolant Temperature Sensor
11. Replaced damaged fuel pressure regulator o-ring
Other diagnostics
1. Intermittent check engine light, code 36, "air switch solenoid circut"
2. Ignition coil replaced with known good, no change.
3. MAP sensor replaced with known good, no change.
4. Computer replaced with known good, no change.
5. Listened to fuel injectors with stethoscope, all are clicking.
6. No gas spitting out of fuel pressure regulator--diaphragm is probably fine.
7. I've got a bit of a coolant leak.
8. Fuel pressure is good.
9. Spark is good
10. Battery is good.
Other recent repairs:
-Serpentine belt
-Radiator
-Fuel pump replaced 5 years ago
Background:
My car is cold start stalling. That is, it starts up great, runs great for the first mile, but once it starts warming a bit I get hesitation during acceleration and stalling at idle. Once it reaches normal operating temperature, it runs great again. I think that this means the air temp sensor is failing. But I can't find it! It's not on my Chilton Manual wiring diagram. It's not on the intake hose. I can't find it on the intake manifold. I looked all through the manual and all over the internet.
Originally it was stalling while driving at speed. So, stuff already done:
1. Replaced camshaft sensor
2. Replaced crankshaft sensor (after these two, it only stalled at stops)
3. Replaced Fuel Filter
4. Replaced Idle Air Control Motor
5. Cleaned out Throttle Body
6. Replaced Spark Plugs
7. Replaced Spark Plug Wires
8. Found and repaired vacuum leaks
9. Replaced EGR Valve. (after this, I noticed that it only stalled during warm up)
10. Replaced Engine Coolant Temperature Sensor
11. Replaced damaged fuel pressure regulator o-ring
Other diagnostics
1. Intermittent check engine light, code 36, "air switch solenoid circut"
2. Ignition coil replaced with known good, no change.
3. MAP sensor replaced with known good, no change.
4. Computer replaced with known good, no change.
5. Listened to fuel injectors with stethoscope, all are clicking.
6. No gas spitting out of fuel pressure regulator--diaphragm is probably fine.
7. I've got a bit of a coolant leak.
8. Fuel pressure is good.
9. Spark is good
10. Battery is good.
Other recent repairs:
-Serpentine belt
-Radiator
-Fuel pump replaced 5 years ago
#2
09-25-2011, 03:50 PM
Here's my question: On my 1994 Dodge Grand Caravan LE, 2WD, 3.3L engine I cannot find the Air Charge Temperature Sensor (also known as the Intake Air Temp Sensor). So...where is it? Or does my car not actually have one?
Background:
My car is cold start stalling. That is, it starts up great, runs great for the first mile, but once it starts warming a bit I get hesitation during acceleration and stalling at idle. Once it reaches normal operating temperature, it runs great again. I think that this means the air temp sensor is failing. But I can't find it! It's not on my Chilton Manual wiring diagram. It's not on the intake hose. I can't find it on the intake manifold. I looked all through the manual and all over the internet.
Originally it was stalling while driving at speed. So, stuff already done:
1. Replaced camshaft sensor
2. Replaced crankshaft sensor (after these two, it only stalled at stops)
3. Replaced Fuel Filter
4. Replaced Idle Air Control Motor
5. Cleaned out Throttle Body
6. Replaced Spark Plugs
7. Replaced Spark Plug Wires
8. Found and repaired vacuum leaks
9. Replaced EGR Valve. (after this, I noticed that it only stalled during warm up)
10. Replaced Engine Coolant Temperature Sensor
11. Replaced damaged fuel pressure regulator o-ring
Other diagnostics
1. Intermittent check engine light, code 36, "air switch solenoid circut"
2. Ignition coil replaced with known good, no change.
3. MAP sensor replaced with known good, no change.
4. Computer replaced with known good, no change.
5. Listened to fuel injectors with stethoscope, all are clicking.
6. No gas spitting out of fuel pressure regulator--diaphragm is probably fine.
7. I've got a bit of a coolant leak.
8. Fuel pressure is good.
9. Spark is good
10. Battery is good.
Other recent repairs:
-Serpentine belt
-Radiator
-Fuel pump replaced 5 years ago
Background:
My car is cold start stalling. That is, it starts up great, runs great for the first mile, but once it starts warming a bit I get hesitation during acceleration and stalling at idle. Once it reaches normal operating temperature, it runs great again. I think that this means the air temp sensor is failing. But I can't find it! It's not on my Chilton Manual wiring diagram. It's not on the intake hose. I can't find it on the intake manifold. I looked all through the manual and all over the internet.
Originally it was stalling while driving at speed. So, stuff already done:
1. Replaced camshaft sensor
2. Replaced crankshaft sensor (after these two, it only stalled at stops)
3. Replaced Fuel Filter
4. Replaced Idle Air Control Motor
5. Cleaned out Throttle Body
6. Replaced Spark Plugs
7. Replaced Spark Plug Wires
8. Found and repaired vacuum leaks
9. Replaced EGR Valve. (after this, I noticed that it only stalled during warm up)
10. Replaced Engine Coolant Temperature Sensor
11. Replaced damaged fuel pressure regulator o-ring
Other diagnostics
1. Intermittent check engine light, code 36, "air switch solenoid circut"
2. Ignition coil replaced with known good, no change.
3. MAP sensor replaced with known good, no change.
4. Computer replaced with known good, no change.
5. Listened to fuel injectors with stethoscope, all are clicking.
6. No gas spitting out of fuel pressure regulator--diaphragm is probably fine.
7. I've got a bit of a coolant leak.
8. Fuel pressure is good.
9. Spark is good
10. Battery is good.
Other recent repairs:
-Serpentine belt
-Radiator
-Fuel pump replaced 5 years ago
you didn't replace the Throttle position sensor? oxygen sensor?, EGR transducer? intake manifold gasket? MAP sensor? PCM? all these things could cause your problems too.
#3
09-25-2011, 03:54 PM
Join Date: Sep 2011
Posts: 15
Likes: 0
Received 0 Likes
on
0 Posts
#4
09-25-2011, 08:09 PM
#5
09-25-2011, 08:10 PM
3.3L, 3.5L & 3.8L Engines
11
Engine Has Not Been Cranked Since Battery Was Disconnected{4}
No Crank Sensor Signal During Engine Cranking{3}
12
Memory Standby Power Recently Lost
13
MAP Sensor Pneumatic Circuit
14
MAP Sensor Electrical Circuit
15
Vehicle/Distance Sensor Circuit
16
Loss Of Battery Voltage Sense
17
Engine Running Too Cool
21
Problem In Oxygen Feedback Circuit
22
Coolant Temperature Sensor Circuit
23
Charge Temperature Sensor Circuit
24
Throttle Position Sensor Circuit
25
AIS Motor Drive Circuit
26
Injector Current Limit Not Achieved
27
Injector Driver Interface Circuit{1}
Injector Control Circuit{2}
31
Purge Solenoid Circuit
32
EGR Diagnostics
33
A/C Cutout Relay Circuit Or A/C Clutch Relay Circuit
34
Fault In Speed Control Solenoid Driver Circuit
35
Fault In Fan Relay Circuit
37
Part Throttle Unlock Solenoid Driver Circuit
41
Fault In Charging System Or No Field Current
42
Fault In ASD Relay Driver Circuit
43
In Ignition Coil Control Circuits
44
Lose Of FJ2 To Logic Board
46
Battery Voltage Is Too High
47
Battery Voltage Is Too Low
51
Lean Condition Is Indicated
52
Rich Condition Is Indicated
53
Internal Problem In Module
54
Fault In Distributor High Data Rate Pickup Circuit{1}
No Sync Pickup Signal{2}
55
End Of Message
62
Unsuccessful Attempt To Update EMR Mileage
63
Fault Error{1}
Controller Failure EEPROM Write Denied{2}
65
Manifold Tuning Valve
66
CCD Bus System
77
Speed Control Relay Circuit
Engine Has Not Been Cranked Since Battery Was Disconnected{4}
No Crank Sensor Signal During Engine Cranking{3}
12
Memory Standby Power Recently Lost
13
MAP Sensor Pneumatic Circuit
14
MAP Sensor Electrical Circuit
15
Vehicle/Distance Sensor Circuit
16
Loss Of Battery Voltage Sense
17
Engine Running Too Cool
21
Problem In Oxygen Feedback Circuit
22
Coolant Temperature Sensor Circuit
23
Charge Temperature Sensor Circuit
24
Throttle Position Sensor Circuit
25
AIS Motor Drive Circuit
26
Injector Current Limit Not Achieved
27
Injector Driver Interface Circuit{1}
Injector Control Circuit{2}
31
Purge Solenoid Circuit
32
EGR Diagnostics
33
A/C Cutout Relay Circuit Or A/C Clutch Relay Circuit
34
Fault In Speed Control Solenoid Driver Circuit
35
Fault In Fan Relay Circuit
37
Part Throttle Unlock Solenoid Driver Circuit
41
Fault In Charging System Or No Field Current
42
Fault In ASD Relay Driver Circuit
43
In Ignition Coil Control Circuits
44
Lose Of FJ2 To Logic Board
46
Battery Voltage Is Too High
47
Battery Voltage Is Too Low
51
Lean Condition Is Indicated
52
Rich Condition Is Indicated
53
Internal Problem In Module
54
Fault In Distributor High Data Rate Pickup Circuit{1}
No Sync Pickup Signal{2}
55
End Of Message
62
Unsuccessful Attempt To Update EMR Mileage
63
Fault Error{1}
Controller Failure EEPROM Write Denied{2}
65
Manifold Tuning Valve
66
CCD Bus System
77
Speed Control Relay Circuit
#6
09-26-2011, 12:35 PM
Join Date: Sep 2011
Posts: 15
Likes: 0
Received 0 Likes
on
0 Posts
#7
09-28-2011, 02:03 PM
Join Date: Sep 2011
Posts: 15
Likes: 0
Received 0 Likes
on
0 Posts
One mechanic who actually looked at the car suggested replacing the fuel injectors, but said he could not guarantee it would fix the problem. I did not have the injectors replaced.
Another mechanic who has not seen the car, but whom I talked with over the phone, said he thinks it is the timing chain. He said that he's seen a lot of old Caravans that have their timing chains go bad around 200,000 miles. He said the camshaft and crankshaft sensors need to be getting proper readings, but a worn timing chain is hard for them to read and needs to be replaced to get them sending good signal back to the PCM. No explanation as to why it runs well when hot.
I'm not sure what to think. A new chain is only $40, but getting it installed will take a ton of work. What do you all think?
Another mechanic who has not seen the car, but whom I talked with over the phone, said he thinks it is the timing chain. He said that he's seen a lot of old Caravans that have their timing chains go bad around 200,000 miles. He said the camshaft and crankshaft sensors need to be getting proper readings, but a worn timing chain is hard for them to read and needs to be replaced to get them sending good signal back to the PCM. No explanation as to why it runs well when hot.
I'm not sure what to think. A new chain is only $40, but getting it installed will take a ton of work. What do you all think?
Trending Topics
#8
09-28-2011, 04:37 PM
I think both mechanic A and mechanic B are complete idiots. I have yet seen a caravan 3.3 need a timing chain and I've been dealing with these since day 1. I personally owned dozens (I'm a licensed car dealer) with 300,000 to 500,000 miles on the original timing chain.
besides I see no correlation between either "mechanics' ideas related to your code 37.
your problem is warmup driveability, runs great hot. have you done a fuel pressure test?
besides I see no correlation between either "mechanics' ideas related to your code 37.
your problem is warmup driveability, runs great hot. have you done a fuel pressure test?
