1983 Chrysler Imperial: starting problems (Long read)

[RWestra@xxxxxxx]

Joel:

 

I have an 81 Imperial and have gone through many of the same experiences you have.  For the past two years the car has worked quiet well.  I use it as my daily driver and it always starts whether it is 10 below zero or 90 degrees.  I am determined to keep the EFI and keep it as original as possible.  When these cars work they are really a nice car but reliability is not their strong suit.

 

I don't have pat answers to your specific problem.  It is intermittent and you would drive yourself up the wall trying to chase it down.  Since it only did it once I would assume it was a fluke and dismiss it.  You may be a little ucomfortable each time you go to start it but that is the way it is with these intermittent problems. 

 

If you are up to the challenge of keeping a great car running like it was intended it can be very rewarding.

 

I would have the following advice:

1.  You are on the right track to obtain the service manuals.   They will be less valuable in troubleshooting than you would like but they go a long way in helping you understand the system and the function of each component. 

2.  I would try to acquire some spare parts.  Some that are known to be good if possible.  They are around but not easy to find.  There are still some out there at a reasonable price.  Particularly pick up a computer, a power module (inside the Hydraulic support plate) and probably a water temperature sensing unit.  Other components would be helpful but not essential. 

Make your appeal to the IML folks.  They are very helpful. 

3.   Check the archives of IML.  There is a lot already written about these EFI systems and they will help you understand the system and analyze what might be the problem. 

4.  Unless you are steeped in electronics I would not get into repairing the specific components.  They are complex and difficult to diagnose.  Change out components to find the culprit.  If you want to repair the suspected component Dick Benjamin (the IML resident expert ) is an extremely valuable resource. 

5.  The electronics seem to me to be sensitive to moisture and humidity.  If your starting problem occured under these conditions the problem will probably repeat under those conditions.  When it is damp out make sure the car is completely warmed up and dried out when you shut it off. 

6.  It has been my experience that these cars start with less cranking in the winter than they do in the summer.  Long cranking cycles are usually associated with high ambient temperatures.  I would expect this is due to fuel vaporaziation and the inability of the system to quickly purge itself of fuel vapor.  I don't know what can be done about this. 

7.  Even though it might seem so, the problem is not always in the EFI.  Make sure the ignition system is in good condition.  This includes spark plugs, plug wires, ignition coil, ballast resistor, and the hall pick up coil in the distributor. 

8.  A common problem is the failure of the air cleaner/hydraulic support plate to seal sufficiently to make sure all the air for the engine is passing the air flow meter.  Check all seals and gaskets from the throttle base to the air horn to minimize leakage.  Also make sure all vacuum hoses are tight and not weathered to the point they are leaking. 

 

This is a lot of what my seat of the pants experience has taught me.  I don't have all the answers but I have a car that is used almost daily for relatively short drives and runs and strarts good.  Mine has just over 93,000 miles on it. 

I have replaced several of the EFI components over the years and have found the computer and power module to be the most troublesome.  I did implement the service fix of grounding the Automatic Shut Down Model to the engine. 

 

Converting to a carbureted set up was an option for me at one time.  My son was parting out a Dodge Mirada and all the components were available to me at no cost, including the fuel tank and intake manifold.  I decided to give the EFI one more shot and I have never regretted it.  A clean conversion that was not done by the factory is extremely hard to find.  I have seen many that are real butcher jobs even though they do start and run. 

 

Good luck on keeping your car running.  It is a real challenge at times but if you enjoy a challenge and a nice running car it is worth it.

 

Use the IML as a resource.

 

                                                                                Rolland Westra

                                                                                Near original 81