Cadillac Deville 1992 (Crank, No Start when Hot)

Cadillac Deville 1992 4.1lt V8 PFI

Customer complain:

-Crank, Start and it runs just fine when it's Cold

-There is a slightly hesitation when he crank the engine like the battery is bad and sometimes It's hard even to notice this hesitation.
(he has put a new battery and starter in order to fix this but it didn't)

-Crank, No Start when it's Hot.
(If he let it cool down, it starts just fine.)

I don't have Scope or Scanner or Wiring Diagrams.
I only have a test light.

I would appreciate it so much if you can help and advise me
as to what I should check.

I moved this topic to the correct location.
You will need to tell us what you are missing when it does not start. These have a fuel pressure test port and you can rent a psi gauge from your local parts store.
A spark test can be done with your test light as long as it is an incandescent style bulb. Pull one plug wire off the distributor cap, ground your test light, then hold it a 1/4 inch to 1/2 inch away from the cap electrode. It should jump a 1/2 inch gap.
We have to know if you are missing spark or fuel pressure first, then we can focus on injection pulse.

Hi

I have No Spark, No Fuel Pressure when it's Hot

I found a Wiring Diagram on Google for the Distributor.
It's from 1995 Cadillac Deville, not 1992 but it looks the same.

Could you tell me if I can do some checks on it with my Test Light?

The 430 PPL/WHT B5 Reference should be power, 5v?
The 453 BLK/RED B3 Reference Low should be ground, 0v?

Is it possible to check my Pick-Up Coil and Primary Coil with just a Test Light?

Hi

I have No Spark, No Fuel Pressure when it's Hot

I found a Wiring Diagram on Google for the Distributor.
It's from 1995 Cadillac Deville, not 1992 but it looks the same.

Could you tell me if I can do some checks on it with my Test Light?

The 430 PPL/WHT B5 Reference should be power, 5v?
The 453 BLK/RED B3 Reference Low should be ground, 0v?

Is it possible to check my Pick-Up Coil and Primary Coil with just a Test Light?

Hi bobby,

Is not possible to check in a conclusive way with test light. You can check some voltages, byut nothing else.

It's better perform basic tests like Paul suggested you.

We need to figure out what exactly you are lossing (spark, fuel, air reading) we need to know where to focus on.

FUEL PUMP CONTROL


When the key is first turned "ON" (key in "RUN" position with engine "OFF"), the PCM will turn the fuel pump relay "ON" for two seconds. This build up the fuel pressure for cranking. If the engine is not started within two seconds, the PCM will shut the fuel pump "OFF" and wait until distributor reference pulses are present. As soon as the engine is cranked, the PCM will turn the relay "ON" and "RUN" the fuel pump. The Oil pressure switch is provided as a backup to the fuel pump relay.