5.0 won\t start April 29, 2006, 03:05:21 PM I have a 88 t-bird with a 5.0 and I can't get it to start. Here is what I have done so far...Its a fuel delivery issue...when I spray starter fluid into the intake, it will run for 5-10 seconds...Checked the inertia switchChecked fuel pump relay and associated wiringJumpered fuel pump to make sure to ran (also checked flow at this point too, I didn't check the pressure which could be suspect)Replaced the fuel filterChecked the voltage on one of the injector leads (it read 2-3 volts, which I assumed was alright because my multimeter would have been giving me a RMS number)Anyone have any ideas? Any help would be great. I'm new to these cars, so I don't know much about the electronics that control the fuel delivery so I'm wondering if that is my problem...Thanks for the help and space...Scott Quote Selected
5.0 won\t start Reply #1 – April 29, 2006, 03:43:15 PM Bad fuel pressure regulator? I'd check that as well. It's on the passenger side right below those "salt and peper shakers" on the upper intake manifold. Quote Selected
5.0 won\t start Reply #2 – April 29, 2006, 10:07:07 PM Welcome. Your fuel pressure should read 40psi. Possibly your injectors are clogged.Check your pressure regulator for sure. Also, I know it's a stupid question, but is there gas in the car? There was a member on another board who after days of searching realized they didn't have gas in the car. Quote Selected
5.0 won\t start Reply #3 – April 30, 2006, 12:09:58 PM Voltage on the injectors should be 12v, iginition on engine off(both terminals)... You'll get lower reading on the red wire while cranking(8-10v) and the other should be pulsing with engine cranking.A bad TPS can also put the engine in dechoke mode and shut off the injectors... Make sure the green wire doesn't have 4-5v on it, should be less than 1v... When in doubt just unplug it, should start if that is your problem... Quote Selected
5.0 won\t start Reply #4 – May 01, 2006, 03:45:11 PM Thanks for the info fellas...I will check those things and get back with the status... Quote Selected
5.0 won\t start Reply #5 – May 28, 2006, 07:43:10 AM alright...just fyi...the previous owner had driven the car maybe 100 miles over the past 4 or 5 years, and hadn't started or driven the car for a year. therefore, the gas seperated and became corrosive, and destroyed the rubber line in the gas tank. that is why the fuel pump would run and I could drain the tank with the fuel pump, but it couldn't build up enough pressure to feed the injectors.Bad gas also eats injector orings:mad: its running now though;) Quote Selected
5.0 won\t start Reply #6 – May 28, 2006, 07:48:55 AM Quote from: TurboCoupe50Voltage on the injectors should be 12v, iginition on engine off(both terminals)... You'll get lower reading on the red wire while cranking(8-10v) and the other should be pulsing with engine cranking.A bad TPS can also put the engine in dechoke mode and shut off the injectors... Make sure the green wire doesn't have 4-5v on it, should be less than 1v... When in doubt just unplug it, should start if that is your problem...I was having a partial throttle misfiring problem, so I unplugged the tps and that problem went away. Can you give me a little more information the tps and checking it? Do I check the green wire when the car is running? Is the green wire the output of the sensor, so I need to check it while the other wires are plugged in?Thanks for the help:) Scott Quote Selected
5.0 won\t start Reply #7 – May 28, 2006, 10:11:31 AM yes and no,, either waywith the car not running..............ground your black meter lead to the intake or somewhere.prob with a stick pin the green wireconnect red meter lead to green wireturn key on onlymanually move the trottle linkage slowwwwwwwlywatch the voltage output on the green wire it willl smoothly move from less than 1vdc to 4.5vdc there about**the best meter to use on this is an buttstuffog (needle) type meterthe tps is a variable resistor so it has a wipper arm moviing against the inside of the tps that has a plastic film with carbon that creates the internal resistance.with the tps unplugged or on the work bench.......hook up black meter lead to the black tps leadhook up red meter lead to the green wireset meter to ohms and you will see the same results as voltage except proportionally speaking your numbers are displayed as resistance.less than a volt or an ohm on the green wire is important and a must have. Without it being less than a volt, you will have a symtom of high idle for starters.the tps is mounted by two screws and if you cant achieve less than a volt on the green, you can use a round file to egg shape the mounting holes of the tps. Once you do this, mount the tps but leave the mounting screws loose. hook up your meter to the green wire and ground you black lead.if your voltage is greater than a volt, rotate the tps CCW (cause you filed it out to allow for this), and when you get it set to less than a volt , snug down the screws and your done.good luck,,,,,,,,scottbtw, if the rubber line you speak of is on the fule pump in the tank, then yeah a new pump would not be a bad idea. I would suggest the super charged 3.8L cougar fuel pump. It mounts right in and puts out better liters per hour than your bosch stock pumpl. Quote Selected
5.0 won\t start Reply #8 – May 30, 2006, 04:21:06 PM Thanks for the response. I have figured out that I'm getting too much fuel to the engine (I put 19 lb injectors in place of 14 lb injectors, opps). But I'm still going to check the tps tonight because it does run better with the tps unplugged.As far as the fuel pump, I did replace it with a 255 lph walbro for a dsm...I happened to have one laying around.Thanks... Quote Selected
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