Chrysler Repair: ENGINE WONT START:

Question

Chrysler neon 2.0L RT   QUESTION: Hello there;
I have a chryser neon 2.0L RT; 2003 model. It had a problem with the engine and I replaced the engine; and later I was told the supplier of the engine sold me the engine for 2001 model. After the engine was put back into the car; it sound like it will start but it doesn't;I replaced the computer box because the mechanic told me its damaged; when I got the box the mechanic told me its not programmed and the car will not start up until its programmed. is there anyway I can by-pass this computer programme issue and drive without it. Iam in South Africa;Eastern Cape.

ANSWER: Hi Lala,
My manual for the Neon is for 2001 (10th digit of VIN is 1) and I also have a manual for 2004, but I don't have the '03 manual. The '01 model had a single overhead cam 2.0L (8th digit of VIN is either a C or an F). The '04 model has (10th digit of VIN is 4) and is shown to have the same 2 engines. The C or F apparently involve details of 'performance' which appear to be related only to the shape/design of the intake and exhaust manifolds. Does the old and new engine look to be identical or not in that respect. View the engine serial numbers if both are available.
So I don't believe the engines are that different, and it is possible that there is an issue with compatibility of wiring plug sockets, but I can verify that point.
I thus believe that there would not be a significant difference in the starting/running of the vehicle whether it has a 2001 of a 2003 engine unless one was a C and the other was an F in which case the computers would be different rather than programmed differently I believe. But I wonder whether the old computer was bad, but maybe the computer that replaced the old one was not matched as related to the C of F basis. In any case the mechanic should have told you which computer to get, C or F. Check with the vendor to see whether there is a difference that is model year-related or not.
The only reason for 'programming' the computer, were it the correct computer, would be if your vehicle has an anti-theft security system called a 'security key immobilizer' which means the key has a fat bulge in the handle that contain a chip. If it has a simple flat medal head than that is irrelevant.
So my thinking, absent the C or F issue, is that the engine has not been correctly installed electrical plug-wise and that is what needs to be resolved. I don't believe there is any 'programming' (other than for security key) that can be done to it which if not done would prevent the engine from starting and running. The only things that require programming (mileage reading for example) do not prevent the engine from running. They only cause a coded fault number to be put into the memory of the computer.
So I believe the 'programming' is an excuse. How much does he want to charge for that? Has he checked for fault codes in the computer memory that may explain why it won't start and run?
Let me know what you learn.
Please read the PS below and respond to it.
Thanks,
Roland

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

QUESTION: The engine does not look different from the previous one; the old computer box showed showed that the memory got erased when the engine was overhaul. The key itself is flat;its just a normal flat key.

Answer
Hi Lala,
One possible cause would be that the plug for the camshaft position sensor and the plug for the crankshaft position sensor are switched. Both are identical in shape and black in color.
The cam sensor has a tan/yellow wire while the crank sensor has a gray/black wire. The other wires are identical.
The memory (of any fault codes that were stored there) is erased just by removing the battery cables. The rest of the computer should not be damaged by that. I have never heard of a computer being damaged in its memory from being disconnected, only the fault codes are erased. Good that you don't have a sentry key system.
So there is really nothing preventing the engine from starting and running based upon the computer. I would compare the part numbers of the old and new computers to be sure that they are the same. If the old computer is bad then when you try to start it there would appear a new fault code in its memory. See if that happens. Same thing with the new computer. See what 4-digit fault codes appear in the memory. You access the codes by turning the ignition key:"on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time.
Then watch the odometer to see the mileage replaced by a 4-digit number(s) preceded by a P.
Let me know what those are and we'll go from there.
So it is either there will be a fault code, or the engine still is not hooked up properly. There are a couple of plugs that look the same which could have been interchanged. The shop should keep trying to get this running. No more 'programming' is needed if you have a proper working computer (could be the old one!).
Please read the PS below and respond to it.
Thanks,
Roland