QuestionQUESTION: Hi Roland well we are still having the same trouble with the car turning off when hot new code that.comes up is 1193 and how can I check the.crank sensor thank you
ANSWER: Hi Sue,
Would you have a reference to the date(s) of our earlier Q and A's? I would like to review those and to know the year/make/model/engine of the vehicle. I went back 4 months to find a question from 'sue' in Florida but couldn't find it. Thanks for your understanding, and also for your nomination and kind remarks about me.
Roland
---------- FOLLOW-UP ----------
QUESTION: The name your looking for is al and the make and model is 2003 dodge grand caravan 3.8
ANSWER: Thanks for that clarification, Sue.
The 1193 code says that the electrical behavior of a sensor which measures the temperature of the air that is coming into the engine is out of the expected range of voltage. The engine uses that sensor's voltage signal to adjust the fuel/air mixture so the engine runs well. It is possible that because of this situation the fuel/air ratio is too rich when the engine is hot so it won't idle. The sensor is located along a corrugated rubber tube that attaches between the throttle body (at the top rear of the engine) and air filter box at the front left of the engine compartment where the air for the engine comes in. So look along that tube to find a small device with a black 2-wire plug (wire colors are dark blue/light green stripe and dark blue/dark green stripe). Take a close look at the wires as they connect from the plug to the engine wiring harness nearby to see if there is any damage to the wires. Then you can use your volt meter (if it also has a resistance setting labeled 'ohms') to see if the sensor is functioning. It should have a reading of 3-4 thousand ohms when cold, putting the meter between the two pins of the sensor (after removing its plug), and then do the same thing immediately after the engine has been run and it is hot to find whether the ohm reading has dropped to a much lower reading of around 1-2 thousand ohms. If either the wiring or the resistance readings are off value then make the necessary repair.
It is possible that the crank sensor may be failing when it gets hot, also. Al has replaced that sensor I believe. You can use the voltmeter to check its function by putting fine straight pins through two of the three wires that are attached to it, located at the engine control module which is located on the left inner fender wall. You would need to find pin 32 on plug 1, and pin 43 on plug 2. What you do is attach the voltmeter to the pins that you push through the insulation of those two wires (brown/light blue on pin 32, dark blue/dark green on pin 43. Then turn the key to the 'run' position. Then use a socket and ratchet handle to rotate the engine via the bolt on the crankshaft pulley while you observe the voltage which should oscillate between 5.0 and 0.3v several times per revolution of the crank shaft. Observe for that when the engine is cold. Then when the engine is hot and it stalls out check to see that the voltage still oscillates the same way it did when the engine was cold. If not, then the sensor is failing when hot.
I hope these two measurement will help resolve the stallng problems with the hot engine.
Thanks again for the rating/nomination. You are entitled to do that again for this answer if you would be so kind.
Roland
---------- FOLLOW-UP ----------
QUESTION: Hi Roland we are using the voltmeter and have it set at 200 k and the reading is 10.6 not very good at this electrical stuff hope you can help thanks again
AnswerHi Sue,
I assume that you have found the intake air sensor and removed its plug. If you have placed the leads of the meter on its two pins and get a reading of 10.6 with the scale set for 200k that means the resistance is 10.6K ohms. That may be OK depending upon the local temperature at the time you did the measurement. Now the next step is to reconnect the plug, start the engine and drive it until the engine is fully warmed up (ideally until the engine dies when it gets hot as you mentioned) and then quickly disconnect the plug and read the resistance again across the pins of the sensor with the plug removed. It should then show a significantly lower reading in ohms than the 10.6k that you measured when it was cold. Let me know what you learn.
Also, check the wires that connect to the plug for any signs of damage. To verify those wires you could check the resistance between the plug's pins and the pins where they connect to the engine controller (using a fine straight pin to penetrate through the insulation there at the controller's plugs). The dark blue/light green wire on pin 1 of the plug goes to pin 37 of the controller plug, while the dark blue/dark green wire goes to pin 43. Those numbers are shown engraved in the plug where the wires arrive at it. If the wires are good then the resistance should read at or close to 0 ohms. Based on the code we would expect either that the resistance of the sensor doesn't change very much when it is heated up, or that one of the two wires is 'open' (reads 200k, e.g. infinite ohms). Thus we would know whether to replace the sensor or repair the wire to cure the code.
Doing these measurements will prepare you for doing the measurements on the crank sensor when the engine is hot/shutdown as I described in my previous answer.
Feel free to do another rating/nomination of this answer if it has been helpful.
Roland
