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Engine will not start,fuel pressure ok,no spark and no injection pulse.sensors check out ok.problem appeared few weeks ago after aborted start.after disconnecting battery and reconnecting after a while engine will start and will be ok for a few day's and the problem will return.

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Try first checking all the connections, then if you can try to use a different battery just to make sure that the battery is still working fine and check also the starter ,becase this can be a problem also with the starter solenoid that may need repair or replacement...

Hope that helps.........

Posted on Sep 19, 2008

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2 Answers

Engine ran roughly then after shutdown wont start. I suspect fuel pump. filter good. And where is pump located?


How long since a tune-up? Check applicable trouble codes? What led you to the fuel pump as being your problem?
Usually if it cranks good but won't start, have a helper crank it, while you visually check for spark at the spark plugs. If spark everywhere, use a gage and check proper fuel pressure and fuel injector pulse.
Only crank the starter motor for a few seconds at a time, let it cool off, a little.
I do realize, sometimes visually checking for spark, can be a pain. Also, checking fuel pressure can be a pain if no Schrader valve, but, not impossible.
I'm not saying the pump can't be your problem, it could be, just check the other issues, also. The fuel pump is in the gas tank.

Apr 03, 2016 | 2001 Saturn L-Series

1 Answer

2003 kia floods..no start hot


How do you know it floods? Fuel injected vehicles should not over fuel the engine unless an injector/fuel pressure regulator is leaking internally or the computer commands a high injector pulse rate based on sensor information. Does it have spark and fuel pressure when the no start condition presents itself?

Dec 19, 2015 | 2003 Kia Sedona

1 Answer

What generates fuel injection pulse on a 1994 geo metro base model? I have replaced alternator, TBI injector, and ECU. Checked relays, fuel pump and filter. Feed and return line are clear. On startup I get...


The PCM (ECU does that) its part of what is called EFI, electronic fuel injection, it's a computer, that gets inputs, and uses those inputs to injector perfectly at ALL times.
what engine? 3cy. or 4? is it TBI injected or MPI injected
1 injector or 4? we need to know that first.
does it run on test fuel for 3 seconds.
when was last time it run perfect, last week last year. what?
first off stop guessing, you can go broke that way.
want to diagnosis it? the steps are easy. if fuel is good..
  1. fuses good.?
  2. CEL lamp glow keyon, if not ECU is bad. or bulb , it must glow.
  3. compression over 150PSI on all cyl. (w.o.t = wide open throttle)
  4. do a 60k, mile tune up yet, filters, spark,. and cam timing belt.?
  5. if not, why wait?
  6. 6: is spark good tall cylinders not just 1? is the timing way off if yes, the cam belt did slip, do not fiddle tiiming, fix the belt. first.
  7. ok it now magically runs on test fuel for 3 seconds and sounds great. so we do fueling last.
  8. fuel pressure tests are next. takes $20 gauge got one?
  9. ill stop here, as fueling tests are long play.l..... ask. if you can get to step 9,

I think all 94 metors are TBI engines, one injector
up to 1997 inclusive.
then the 1998 offered 4cyl, MPI injected engine.


have you learned how to use flash codes (DTC) yet?
insert jumper , key on, see CEL lamp glow and flash 12s'
the crank for 5seconds, see if the flashes go to 41 or 42?
bingo if yes.
the TBI allows the mech to watch injection, at the TB.
with top hose off. you can watch it inject as person 2 cranks.
does it?
the ECU brain cuts fuel at the first sign of:
  1. lost spark (to stop fires)
  2. lost Cmp sensor, same .
  3. TPS ground wire busted and ecu things foot is W.O.T (super secret unflood mode) (or TPS cracked in half inside)
or total loss of fuel pressure.

Mar 27, 2015 | 1994 Geo Metro

1 Answer

Car cranks but will not start


This could go several ways #1 engine mechanical check cranking compression should have 125 psi or greater in all cylinders if low but even squirt oil (1/2 oz.) in 1 cylinder and retest goes higher then rings sealing has been lost. if uneven check timing belt for jumped or misalignment. #2 electrical does it have electrical spark to plugs crank engine with a spark plug connected to spark plug wire laying plug on engine can you see spark? No test ignition coil wires with a logic probe both terminals will be red with key on one will flash red/green when engine cranking does not the primary ignition needs repair Ignition module? or pick-up coil/ crank sensor. #3 fuel system pressure and injection pulse. injection pulse can be tested with logic probe DONOT USE A TEST LIGHT YOU CAN RUIN THE ECU .

Mar 21, 2014 | 1998 Mazda 626

2 Answers

I can smell that my jeep is not burning all the fuel it is consuming and my fuel milage is down. There are no engine codes and it seems to have a decent amount of power. I have been running some fuel...


First thing I'd do is to remove the spark plugs and see how they look. Black plugs will confirm that something is causing it to run rich. I'd also look at the exhaust and see if there is any black smoke.
also check the running temperature of the engine (should run at near 210 degrees (f))...too cold can cause the computer to richen up the fuel mixture. If you smell raw fuel, take a good look at the fuel lines etc to make sure you have no leaks. Your throttle position sensor and map sensor have a large influence on fuel consumption as do the O2 sensors. In fact, all the engine sensors work together as the computer takes in all that information in order to decide where to put engine timing and fuel pulse length and frequency. It is possible to have one or more sensors just out of range enough to alter the fuel mix without setting a code. To find a problem like that you'd need to do individual component tests as outlined in chilton or haynes manuals, writing down your test results and comparing those to expected values also listed in the same publications. I'd also check all vacuum lines and for leaks at the intake manifold a small leak can change what the sensors see.
Tests take time and patience. They are necessary though.

Dec 10, 2010 | 1998 Jeep Cherokee 4WD

1 Answer

1989 toyota land cruiser.driving on highway engine died.turns over good but wont start.has a full tank of gas.put in new battery and altenator a few weeks ago,been running fine.checked the fuses and found...


Hi.

Re:new battery and altenator
If engine turns over battery and altenator are OK.

Re:checked the fuses and found a few were blown.
Effectively those may be symptoms of a wiring problem. If a job had been carried recently, undoing and re-connecting the wires to access the part(eg. alternator) may have contributed to the problem.

Check all fuses, with attention to fuel pump fuse. Check the connectors to fuel pump, eventually read volts at pump and nsure that fuel is circulating
Check air intake and connectors to air intake sensors (MAF sensor), check connection to crank sensor and O2 sensors.

The blown fuses may also have been incidental. If you did not find anything, troubleshooting must proceed as usual, checking distribution, fuel pressure, and then factors that can affect the ignition.

Remember that after a prolonged and failed attempt to crank the vehicle, the cylinders will be flooded and the car will no start (wet plugs- no spark).

Check if there is spark on all cylinders. This can be done removing one by one the spark plugs wires and putting them near to the engine block while someone else try cranking. You will see the spark.
If there is no spark, then you have a coil/distribution problem. test coil by reading volts in and impedance (coil must not be open). I think this engine is not distributorless. Check distributor cap and wires. If you have disconnected spark plug wires after the problem, also ensure that wires are connected in right order.

Once you are sure that there is spark, check fuel delivery and engine control. This part will take longer.

I uploaded here engine control diagrams and other documents that may help.

Regards.

Sep 08, 2010 | 1989 Toyota Land Cruiser

2 Answers

I checked my spark plugs and have a spark going to each plug. I changed the fuel pump thinking I didn't have enough fuel pressure. I sprayed some starter fluid in the intake and it started for about 5...


If you are getting spark and the engine tries to run on starter fluid, then you have lost fuel. Check that you are getting injection pulses at the injectors and check the fuel pressure at the fuel rail at the injectors. Check for power to the fuel pump when the engine is cranking, If you get no power to the fuel pump when cranking the engine, check fuses and relays. If the pump is running but you have no fuel pressure, check the fuel filter and fuel pressure regulator and replace any that are faulty. If the injection pulses are missing, check the supply relay which supplies power to the injectors first ( the injectors are earthed by the ECU) Disconnect one of the injector plugs and using a test light (buy one from a auto parts store) clip the end to a good earth on the vehicle body, switch the ignition on but dont start the engine, then probe the two connections in the injector plug. One of these connections should be active all the time with the ignition switched on. If it is, you may have a sensor failure (crank sensor etc), if it is not, check fuses and supply relays. A word of warning, the wiring you are dealing with is connected directly to the engine control, if you make a mistake, you can cause irreparable damage so if you have any doubts, take the vehicle to a professional..

Jun 28, 2010 | 2002 Mitsubishi Lancer

2 Answers

Has all power and still wont start it has a spark it is a 2.5 4 cylinder 1996 the spark is wite i checked the timming could it be the crank positioner


Check the timing belt they are known to loose teeth and slip when old I've seen them be in perfect timing on the wrong cylinder! 80k /belt

Jan 14, 2010 | Jeep Wrangler Cars & Trucks

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