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Engine wont start



I installed a 1990 Mustang 5.0 into my 1968 Ford Bronco back in 1994.  The car has always run very well.  It starts instantly.  Recently the car sat for a very long time.  Perhaps a full year without starting and probably 1.5 years on the fuel in the gas tank.  The gas tank is new since 2008 along with fuel filters and fuel lines.  Anyhow when I started using it again, it started just fine albeit a bit smoky and such but it started and drove for a few days.  Then it began to have a difficult time starting one day and once started it was running rough.  It did run, and I parked it in the garage when I was done that day.  The next day I could not get it to start.  It seemed to "catch" once in a while, but never run.  I figured a clogged fuel filter, so I purchased and installed a new filter.  No change.  I removed a spark plug and confirmed that there is spark.  I got a code reader out and it gave me: (81,82,85/66,95).  I saw mass air, which made some sense, so I purchased a new mass air sensor, and no luck.  I'm not sure what step to take next in troubleshooting.  The most recent code reading after the mass air had all the same codes but 95 is not on the list any longer.  Car still refuses to run, and just barely tries to "catch".  Just running the starter endlessly.

Could my injectors be completely clogged?  Could I have lost the processor?

Any advice and direction would be appreciated.  Thanks in advance.

I would suspect bad gas with alcohol in it led to a fuel pump failure.  Do you hear the fuel pump come on when you  turn the key to the run position?  If not check the relay for it and the fuse.  Also I would want to put a meter on the wiring and verify voltage is present when the key is on before I dropped the tank to replace the pump.

On the other hand it could be a hundred other things.

The fuel pump is definitely running. I can hear it run and the return goes into the filler neck and I can hear it draining into the tank for a few seconds after the pump stops. So that means fuel in fuel rail. I've not checked pressure. Looked for gauge at local auto store but they did not have one rated for fuel injection pressures.   Thanks

Here is a test procedure link that might help

ok, I found the problem and have fixed it!!!!!  I needed to rent a fuel pressure gauge from Oriley auto parts.  What a deal.  They sell one for $100 but you can rent it for 48 hours for free.  Anyhow when I hooked it up I noted a very low fuel pressure.  Next I disconnected the fuel line from the fuel rail where the incoming fuel comes and pointed it into a container to see how fast the fuel pumps when the key first turns on.  Almost nothing came out.  Given that I'd already changed the fuel filter last week, the next place to look is at the fuel pump.  Thank goodness I had cut a hole in the floor of my Bronco, and installed an access cover, when I installed the new tank.  I added this access cover for just this possible event.  Anyhow, I removed the access cover and then pulled the pump up out of the tank and at first everything looked normal, but then on closer examination I found that the short length of hose that runs from the pump to the flange on the top of the tank was crumbling.  On closer examination it shows signs of leaking.  So my pump was pumping in circles inside the tank with very little going out to the engine.  I replaced this hose, reassembled and the car instantly started and runs like a champ again.  Thanks for your help and I hope others might find this useful in the future.

Best Wishes,


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