[mintax]

Hello dear cadillac community, most sincere salutations from Turkey / Ankara

First of all i want you to know im soo desperate and hopeless about this particular issue of my Cadillac Seville STS 1994 model car. Manifold keeps exploding everytime we press the starter. It literaly exploded like a bomb..Till now this problem repeated itself 3 times. Technicians say its an electrical problem after trying too many ways to fix it. Another assumption is the brain. They assume the brain is not sending correct data. Do you guys have any further idea about thisproblem? Or do any of you have ever had a problem like this ? Technicians ask me to find schematic electrical diagram of this model which i couldnt find after a long search online. I need to find this diagram too. You have any idea where can i get it online...

pleease please help me ..

 

[Submariner409]

Good morning and welcome to CF !!! Retired U.S. Navy submariner - been to your lovely city many years ago. Incirlik airbase.

For the GM/Cadillac service manuals and all electrical diagrams for your car either find a paper service manual set on eBay or subscribe the car to the online service manuals - www.alldatadiy.com. You want the genuine manuals published by www.helminc.com.

Your car has its own built-in trouble code system. Use the correct model/year set of instructions (OBD1) in the below link. It comes from the thread (discussion) "How topull codes" up ^^ in the sticky threads at the top of this discussions page.

How to pull codes (DTC's), list of OBD1 &amp...

To check for Diagnostic Trouble Codes stored in the computer, turn the ignition on, then hold down the OFF and WARMER (for digital dash) or OFF and passenger-WARMER buttons (for analog dash) or OFF and "Info ^" buttons (if you have temperature dials) until all of the dash lights come on. The...

www.cadillacforums.com

I doubt there is anything wrong with the PCM - "brain". It's more likely an ignition timing sensor or fuel leak - maybe from the Fuel Pressure Regulator located inside the intake manifold.

1994 CADILLAC SEVILLE 4.6L V8 Fuel Injection Pressure Regulator | RockAuto

RockAuto ships auto parts and body parts from over 300 manufacturers to customers' doors worldwide, all at warehouse prices. Easy to use parts catalog.

www.rockauto.com

Here is the diagram for your waste spark ignition system.

 

[Ranger]

I'm leaning towards a leaky FPR or fuel line inside the manifold.

Remove the cover and turn the key on to energize the fuel pump and pressurize the fuel lines, but DO NOT crank the motor with the cover off. Any leaks should be pretty evident.

P.S.
When replacing the cover, do not torque them down too tight against the rubber grommets. The manifold cover is designed to lift and vent in the event of a manifold over pressurization (backfire). I forget the exact torque setting, but it is not too much more than finger tight. Maybe someone with the correct torque setting will chime in.