I am having the same problem, so far, I have found the code refers the the EGR System. I will post more about what I find out.
P0340 is error code for Camshaft Postion Sensor Circuit Malfunction
Engine codes start at 11 Could it be 55 which means N/A
35- idle air control (iac) valve/ circuit
Diagnostic Code 12 on a 1995 Grand Cherokee just means that your battery has been dead or disconnected within the last 50 ignition cycles.
My engine light came on the error code is P2179 what does this mean
engine fault code p1607
What numbers are you talking about? It will tell you the displacement and a engine code. The engine code is used at dealers and garages.
There are pages and pages of things that can cause a check engine light. You need to have it checked with a scantool. Then the code can be diagnosed and repaired.
code e38
Trouble code P0320 means:Ignition/distibutor engine speed input circuit malfunction
code 0093 what does it mean
Not sure what you mean but Geo's are made by Suzuki and use Suzuki engines.