95 Impala LT1 turns over but will not start replace fuel pump, distributor, plugs, wires,sensors. Was hard to start an to get it to stay running, now it won't start or if it does it cuts right off
it generally helps if you post your location (city/state) you may find you have an experienced local member willing to stop and help,
that being stated, pulling trouble codes is the first step, and yes as was mentioned check for the fuel pressure, oil pressure and ignition spark, as a way to, locate, isolate test and cure the issue,
it sounds like the oil pressure sensor is not allowing the fuel pump too run long enough to maintain fuel pressure or low oil pressure is preventing the ignition from firing, isolate test and find the cause.
whats the fuel rail pressure?,
how long does the fuel rail stay pressurized after the ignition keys turned off?whats the engine oil pressure?,
and what are the trouble codes ?
can you post clear pictures of the spark plugs?
what do the cylinders read on a compression test?
Id get out a multi meter and check all the fuses ,especially the injector, ignition, and sensor, related fuses, and Id check all the relays and grounds.
If your engine has a knock sensor ,check your crank position sensor , Id suggest replacing it and testing your fuel pressure regulator.
while it might seem intimidating , its simply a case of checking for consistent fuel pressure, compression, oil pressure, and properly timed ignition spark, and if you don,t have those, you need to find the reason and correct it.
btw lt1 have an opti spark ignition, not a distributor?
you'll want to have a few basic diagnostic tools and ideally a factory shop manual for your exact year make and model car, test the fuel pressure in the fuel rails, when you turn on the key the fuel pump will kick in and pressurize the fuel rails, once the keys turned the fuel rail should pressurize,it also should retain that fuel rail pressure for at least 5-10 minutes after the key is turned, if the pressure, in the fuel rails drops rapidly you have either have a defective fuel pressure regulator or leaking injectors, temporarily plug off the fuel pressure regulator,return line, as a test, too test /verify if its the fuel pressure regulator or the injectors, if the pressure remains high significantly longer with the fuel pressure return line plugged its defective, if it still drops rapidly it the injectors
obviously you'll need to know where the fuel pressure regulator is, so you can use a fuel pressure gauge to monitor the fuel rail pressure.
where the fuel rail shrader valve is where the return line is, how to temporarily block it off to test.
GET A SHOP MANUAL
http://repair.chiltondiy.com/Pub/DIY/Product.aspx?ca=Repair&b=3354
http://www.harborfreight.com/fuel-injection-pump-tester-92699.html
http://www.harborfreight.com/5-in-1-dig ... 98674.html
http://www.harborfreight.com/fuel-injec ... 92699.html
HERES A FEW USEFUL, related bit of info and LINKS YOU MIGHT WANT TO LOOK THRU
and yes they should all read very closely) then you need a noid kit for a G.M. fuel injection system, these are basically little lights that light as the injector pulse hits them that you plug into the injector harness,after you remove the harness from the injectors, they plug into the harness just like an injector, if you try to start the engine and they blink on and off the pulse is reaching the injectors thus proving that the injectors get the pulse, each injector should get a pulse and you should see each noid light flash, if you don,t theres an electrical or wiring issue, that must be addressed.
injectors normal state is CLOSED they open only with a electric pulse, the duration of the pulse controls the volume of fuel flow
carefully visually inspect your cars wire harness for corrosion ,loose or broken or shorting connectors or wiring, obviously getting the wrong electrical pulse, a grounded or shorted connector will cause problems.
a NOID light can be used to test, the pulse is intermittent if plugged into the cars wire harness and its more likely the injector needs cleaning
http://www.harborfreight.com/11-piece-n ... 97959.html
as much as it might seem like a waste of time,
carefully reading links and sub-links,
is very often the fastest way to solve issues
viewtopic.php?f=50&t=3110&p=12074&hilit=multi+meter#p12074
http://garage.grumpysperformance.co...-won-t-start-intermittently.14212/#post-72158
http://garage.grumpysperformance.co...p-after-running-out-of-fuel.11309/#post-51444
http://garage.grumpysperformance.co...le-shooting-flow-chart-info.11536/#post-71845
http://garage.grumpysperformance.com/index.php?threads/c4-c5-corvette-trouble-codes.2697/#post-69239
http://garage.grumpysperformance.com/index.php?threads/1990-corvette-no-spark.13857/#post-70888
http://garage.grumpysperformance.com/index.php?threads/optispark-ignition-info.628/#post-52417
http://garage.grumpysperformance.com/index.php?threads/fuel-pressure-regulators.635/
http://garage.grumpysperformance.co...ts-differences-useful-links.13141/#post-68543
http://garage.grumpysperformance.co...and-verify-each-possibility.11219/#post-50642
http://garage.grumpysperformance.co...shaft-position-sensor-p0336.10378/#post-42861
http://garage.grumpysperformance.com/index.php?threads/92lt1-runs-like-crap.10370/#post-42739
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