40 psi but not starting

Discussion in '94-95 5.0 - Specific' started by jwhisl, May 7, 2016.

  1. jwhisl

    jwhisl Active Member

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    Anybody know what sensors could cause a 94 gt not to start? I get a solid 40psi when cranking bur it will only start if i put gas or starting fluid in the intake tube. Also my fan wont come on and my temp gauge isnt reading a temp. I have a brand new professional products fpr installed today and dialed in at 40psi at idle.
     
  2. 07GtS197

    07GtS197 Well-Known Member

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    Sounds like a bad crank position sensor or you somehow tripped your fuel pump cutoff in your trunk but I think that'll turn the fuel pump itself off so it wont turn on at all.
     
  3. Frank.JD.Perez

    Frank.JD.Perez Well-Known Member

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    +1

    is it trying to turn over or is it cranking but not starting? the CPS could be faulty or it could be unplugged. luckily a new one from autozone is like 20 bucks though so start there
     
  4. jwhisl

    jwhisl Active Member

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    It cranks but wont start. I can get it to run if I spray starting fluid into the intake tube then hold down the gas pedal while cranking. I even drove it a short distance today after forcing it to start. I adjusted the fpr to 40psi at idle and it pulled pretty good even without a tune. This engine was originally in a fox body. Where should that sensor be?
     
  5. Rob04Mach1

    Rob04Mach1 New Member

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    Did you have this problem before this ?
     
  6. RichV

    RichV Well-Known Member

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    94/95 GT does NOT have a crank sensor.

    I would have to say either the injectors are bad/not firing, wrong firing order set on the distributor, general timing is off, fuel in the tank is bad or something related.

    If you unplug the coil and crank it for 10 seconds, stop for 30, crank for 10, do this a couple of times. Pull a plug, does it have fuel on it? Possibly rule out the injectors. How do you know you have 40psi of rail pressure?
     
  7. jwhisl

    jwhisl Active Member

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    The car was built from a shell. I thought it might have a bad fpr so I replaced it first with a stock replacement then with the adjustable. I bought a pressure tester and put it on the schrader valve. I get a solid 40 psi while cranking and at idle after I force it to start. I will try pulling spark plugs to check for fuel. I put 4 gallons in it a couple weeks ago. There was probably 2 or 3 gallons in it already that had been there for a year.
     
  8. jwhisl

    jwhisl Active Member

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    Dont know if any of this matters but I am running procomp 210cc heads, 24lb injectors, b303 cam, typhoon port matched intake, 75mm tb, msd coil, and a cobra ecu
     
  9. stingracer

    stingracer Member

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    Try reseating your ccrm. Disconnect and reconnect. Takes a minute to do.

    Sent from my Nexus 5 using Tapatalk
     
  10. jwhisl

    jwhisl Active Member

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    Ill try that. Thanks
     
  11. ttocs

    ttocs Legend

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    have we started as simple as checking fuses? If not you might wish later you did. Takes 2 mins to pull/inspect each fuse, don't forget the box under the hood.
     
  12. jwhisl

    jwhisl Active Member

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    I did check all the fuses a while back but it couldnt hurt to go back through it and double check. The car has been sitting for about a year now and I'm just getting to where I can work on it again.
     
  13. Rob04Mach1

    Rob04Mach1 New Member

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    Ok so your saying the car was totally rebuilt, hasn't ran for a yr, has heads, inj's cam, intake, tb, a cobra ecm, and you thought it had a bad fpr...
    Has it ever been running correct with this exact set up ? OR is this the initial start up with new mods (and what were those new mods) ?
    Have you re-installed your custom tune ? What are you using for a tune, is the tuned for this exact set up and mods ?
     
  14. jwhisl

    jwhisl Active Member

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    This car has never fired right up with this setup. Ive been slowly replacing things as I went along but the car sat a year untouched. First I was only getting 9v at the pump and I fixed that. Before that I thought it was a bad pump. This is the 3rd pump. I plan on replacing all the sensors one by one since I have no idea how old sone of them are. I do not jave a tune yet, just a J4J1 ecu. I know it will need a tune to run perfectly but my biggest thing is to get it to start and run without a can. Ill be taking it to kansas for a dyno tune.
     
  15. jwhisl

    jwhisl Active Member

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    I know this is an old thread but I found my issue and thought this may help others as I have seen similar posts o numerous forums. First, my throttle position sensor was bad. at the time I didn't know how to test voltage from the sensor but once I did I found I was getting the wrong voltage. I read that a bad TPS can cause the ecu to think the engine is flooded and cut voltage to the injectors. That's why I could build pressure but lose it after a few seconds. I hope this helps anyone that may have the same issue.