1995 Dodge Caravan 181Kms V6 3.0 L has engine light comes on after it warms up anyone with similar problem any sol

 

A water temp sensor or O2 sensor will kick the light on after warm up.

But have the codes pulled before you replace parts. It's cheaper and more accurate that way.

Hope this helps,

Bob

 

There are literally hundreds of things that can cause the check engine light to come on. Unfortunately you can get the codes pulled at the local Auto Zone because it is pre OBDII. You will need to have it diagnosed. It is possible, if you have an AAMCO location near you that they will actually pull the codes for you for free. There may be some other places that will pull codes for free, but most actual shops will charge you a diagnostic fee. If you get the codes pulled post them here and we can help you out.
Hope this helps ya,
Billy

 

I took the van to aamco location they checked it and found three things 1. Engine stays cold too long. 2.water temp sensor send too much voltage. 3. EGR Valve has open circuit. I don't know what to do now I need your help because

 

I'd ohm check the EGR solenoid and the water temp sensor and make sure the basics of the coolant system are operating correctly i.e. coolant, thermostat, no leaks, no air in the system, etc.etc.

Good luck

 

Second that. Engine staying cold too long could be either that it is actually staying cold -thermostat stuck open a possibility - or it's warming up properly but the sensor circuit is not properly sensing the coolant temperature.

Are you handy with a meter?

 

what resistance the egr solenoid and coolant temp sensor should have and where they will be located the haynes manual i didnot find much help please help

 

The EGR valve itself will be close to if not on the exhaust system and I believe it is on the drivers side of the engine, back side. The solenoid that controls it will be upstream of it. Coolant temp sensor(ECT) will be located usually on the T-stat housing which is on the engine and connected to the upper radiator hose. The resistance spec for the ECT will depend on the temperature of the coolant at the time of the test. So cold engine = low ohms eg. 40 and hot engine = high ohms eg. 100. Just throwing out numbers. With both sensors you do not want infinite resistance if you do then it's replace the sensor time. ---> Most likely, but you could also have wiring issues, too.

 

Hate to dispute an ASE Guy, but doesn't the resistance go DOWN as temp goes up? For instance if you short the terminals (essentially "0" resistance) on the sensor for the temp gage, it pegs the meter. Does the ECT for the computer input work the reverse from that?

 

There are two different types of thermistors. There is a Positive Temperature Coefficient (PTC) and a Negative Temperature Coefficient (NTC). With the PTC the resistance goes up as the temp goes up. With the NTC the resistance goes down as the temp goes up. So both of you are correct in a way. The only thing is that on this particular vehicle most likely the temp sensor is an NTC thermistor.
You can test the items as directed or replace them just as easily. I dont recommend throwing parts at a vehicle, but sometimes things are obvious and just as easy.
1. Engine stays cold too long. 2.water temp sensor send too much voltage. Both of these codes are most likely the temp sensor, but before you replace anything look closely at all of the wiring. Rodents love to eat wiring so this is always a possibility.
3. EGR Valve has open circuit. Pretty cut and dry. This is most likely the EGR solenoid. The EGR solenoid comes with the EGR valve.
Billy

 

Thanks for the clarification, Billy.

 

I took off the egr valve cleaned it, clean the engine side ports and cleaned the plunger on valve and it worked I get no check engine light anymore but on coolant side i had to change the sensor and thermostat both because the sensor was shorted out and thermostat was not working proper so i changed it while i was cleaning the coolant system. now it work fine and i thank all of you for your help.
One more thing I want to know that will those code clear itself or we have to do some thing, if we do, What? Thankyou again for your help

 

Disconnect the negative battery post and leave it off for a bit. This will clear all learned items in the PCM.
Billy

 

I disconnect the neg terminal and after one hour driving check engine light came back on. the code comes on 31. according to haynes manual purge solenoid circuit open or shorted condition where do i find purge solenoid on this van and what to do with it please help me again
Thankyou in advance