I just purchased this truck and hope to get her running right asap under a tight budget. I have the dreaded code 27 on my hands and haven't attempted much to fix it yet. I plan on doing a full tune up on it along with new thermostat and radiator cap. I am also replacing the brake master cylinder de to a spongey pedal and i may have to do a temporary head gasket fix for now.

 

I forgot to mention it is a 1992 dakota auto 4x4 with 123xxx on the odometer

 

When I bought my Dakota from Scamslist, it had code 27, but went away after I replaced the battery post terminals. After I replaced the Thermostat, I damaged the 2-wire temp sensor and code 27 returned, but went away after I replaced the sensor. Code 27 arose again after replacing the fuel module because I didn't plug the wiring harness in far enough.
I got all my help from other users on this forum and never fails.

 

Most likely it is a failed injector or bad wiring possibly the power splice that connects all the injectors to each other. At last resort the pcm.

Try to find out which injector it is. Unplug each injector when it is missing, and find the one that doesn't cause it to act up more than it is. Also most hand held code readers can tell you which cylinder it is.

 

I am looking into finding the code scanner i have. The one thing i did notice wa that it looked liked someone spliced i a new injector pigtail on the passenger side rear injector and i dont think they used weather proof butte splices. i will look into the master splice for the injectors and at the moment it is a little hard to get the connectors off of the injectors. is there a trick to unplugging them without breaking them?

 

You could slide the end of a flat head screwdriver under the tab just enough to unlock it and wiggle it (injector connector) back and forth while pulling it out. Mine seemed to be super glued in, but eventually they came loose.

 

Ok I will try that this weekend. I don't know if this helps any either but I forgot to also mention that the truck is hard to start after sitting a while. Could this have something to do with the code 27 and the coolant temp sensor? I basically just bought this truck and am trying to get her to pass nj state emissions so I can drive her daily. I plan on buying the 3m 3 step fuel system cleaner kit and also doing a tune up on her in the near future.

 

I disconnected the injectors one at a time and found a great change with only one injector. I also hooked up the scan tool and it said something about inj 1 not functioning properly. I left the scanner hooked up and watched the coolant temp cause i just replaced the thermostat. the temp peaked at 125 and i put the oe 195 thermostat in. could this be a bad sensor causing my problems? tomorrow morning i will hook the scan tool up and see what the temp is before start up. could the code 27 also be caused by worn ignition system components?

 

I am going to replace my coolant temp sensor asap becuase i went out to check what it was reading this morning. The air temp is 37f and the engine said that before starting it that it was 100f.

 

Maybe it's suffering from hypothermia. The final stage is feeling increased warmth.
Interesting that the temp there is 37 and 35 out here in the Mojave.
I've never seen frozen windshields before.