96 Crown Vic Police PKG Engine problem
I have a 1996 Crown Victoria Police Interceptor with 106k on the engine. I do understand these engines are put through hell especially ceing this was a state trooper's unit.
The problem I've been having is that when on a cold start, the car seems to run fine (other than the #3 misfire which i have no problem with right now) But after driving it say, around the block like just a minute ago, under heavy acceleration (and after a short while under ANY acceleration) the engine seems to want to stall. The more I press the gas, the harder it wants to stall. The engine however does NOT usually kill. only a few times has it killed after running for a few hours. When i force this condition, there is a deep thumping noise at about 500-600 bpm. At least I believe that's close. I'm going to try to attach an audio file I just record a few minutes ago for better diagnostics. Also when this condition is forced, every now and then there is a loud *POP* that comes from the intake. (i figure it's a backfire only coming from the intake rather than the exhaust).
When I first started having these problems, the car had actually died going down the road (fuel pump gave out). So I had the pump changed out and the tank flushed out (car sat up for 5 years). I drove it off the yard there and for the rest of the night it worked superbly. Then, the very next day, it starts up again, shortly after i noticed that there was a loud whining noise coming from the fuel pump location (This could be heard from the inside of the car while driving, and even more coming down the road, lol) The car then started to act as it did when the pump started going out the week before.
I did bring the car back to the mechanic and they said the pump was fine and there was nothing they could do without charging me more money to take my s**t apart and look at it that way. I know there's a better way to go about this than that. I don't like having to pay someone else to do something I can do myself.
These are the things I've researched about and tried so far:
Changed fuel pump.
Changed fuel filter.
Changed condenser sensor (separate problem)
Dissasembled and cleaned off wires on the Mass Airflow Sensor (no buildup found)
Ran injector cleaner through fuel system (no help)
Used a long screwdriver to confirm functionality of all 8 injectors (all good)
Checked Throttle Body for buildup, not much found so did not try to clean out.
Other possibilities not yet looked at:
Distributors (was told that the right one may be putting off less power then the left)
Electronic Ignition (Unsure if this model has that)
Clogged Injectors (Seems unlikely since car runs fine on cold start)
Clogged Fuel Lines
A few more sensors
As I stated before the #3 cylinder is dead. The oil ring is gone and there is a oil-burner (spark spacer) on the spark plug. #4 may also be starting to burn off. Spark plugs are NOT running recommended performance (plugs are too weak for cars) but this has not stopped it from running right on cold starts and when i first got the car. I've ruled out many possibilities and am now down to almost nothing. I need advice on what to look at next. I'm hoping this is just a simple fix, like it usually is for me when I have what seems to be a major running problem in a car. This car has not been driven other than today in almost 2 weeks now. I want my car back, lol.
That's all the information I can think of right now, I may post again updates on anything I've looked at or symptoms I've found before a reply is made. Will try to post the audio file now.
Thanks in advance!