Dodge Repair: 1993 dodge caravan 3.0L: code 27, exhaust gas recirculation valve, exhaust gas recirculation

Question
QUESTION: i have a 93 dodge caravan 3.0l with code 27 ownly when the van is at operating temp and it sit for 10mins and i start it up still hot and it sets code 27 injector 6  i replace injector cuz i put in a doide lite and it flashed when started  and still same problem if i let thr van get cold and when i leave work it runs good never runs bad when running just when i restart it hot then it runs real rough lack of power  until it cools down after sitting runs ok   need help
thanks  bob

ANSWER: Hi Bob,
If you are certain that it is #6 injector, then I would suggest that you verify that there is a good connection between the dark green/orange wire at the autoshutdown relay and that same wire at the innector plug (shaking the harness gently while checking), and similarly check between the brown/dark blue wire at the injector plug and pin 58 of the 60-pin plug at the pcm on the left fender side shield.
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Here is what I answered earlier today:
I wonder whether the problem is the injector, because that should not be temperature-related as you describe. I would suggest that you locate the exhaust gas recirculation valve and try spraying some WD-40 on the valve stem where it enters the body of the valve. If that valve is sticking slightly open when it gets warm then that can cause the sort of problem you describe. The valve is in a small pipe that branches off the exhaust manifold (front on the 3.0L, rear on the 3.3/3.8L). It has a round vacuuum actuated top, the valve body is mounted to the pipe, and between those two parts is a flange inside of which you will see the valve stem which has a slot in it that lets you move the stem back and forth with the tip of a screwdriver. Spray the stem where it enters the body, then move the valve back and forth to be sure it moves freely and that the internal spring-action causes it to close to a dead-stop.
If you believe the problem is the injector for cylinder #6, then you would do well to try wiggling the connector and harness while the engine runs to see if there might be a wiring problem that is causing the code. It can  either be a bad injector OR a problem with the wire that runs from the pcm to the injector.
Are you sure it is injector #6? The 27 code is not specific as to which injector circuit is bad.
Let me know which engine (L) you have and I can tell you the wire connections at the pcm for each injector and you can check those out for continuity using a continuity tester or ohm-meter while gently shaking the wiring harness.
The last possible cause, related to temperature is the coolant temp sensor is not accurate. If you have an ohm-meter you should find that reads around 1,000 ohm when the engine is hot. Otherwise if it reads several thousand ohms when hot then that would cause a poor mixture and rough idle.

Please 'rate' my answer (see below).
Roland

---------- FOLLOW-UP ----------

QUESTION: it is code 27 injector circuit   my scanner say injector 6 circuiti did replace 6 and no change when van gets warmed up  
idid check egr valve with my vacuum pump and it hold vaccum and i can see shaft moving in and out  egr ok i even unplugged my erg valve on way to work and it still run rough when warmed up i also check temp. sensor on scanner and it ride 210 so that is working i did listen to the injectors and number 2 sound not as loud as the other ones and when i unplugged the injector it did not run any different  unplugging the other ones it ran rougher  i am going to let it cool down and listen to injector when cold to see if it is louder injector can run bad when they get hot  i did the check for asd relay all checks ok  
so i think maybe i replace wrong injector or i have a bad pcm

Answer
Hi Bob,
Your noticing that injector 2 is not so loud and that disconnecting it didn't make things worse makes me agree that #2 may be the problem. It would appear that the temp sensor is accurate assuming that the engine was indeed operating at around 210F at the time. I hope that changing out the #2 injector solves your problem.
Thanks,
Roland