Mechanics

CRANKS BUT WON'T START - INTERMITTANTLY

Nissan Pathfinder

I have a 1999.5 pathfinder SE with 245,000 km, V6 3.3L and all of a sudden it wouldn't start, only intermittantly.

When I just turn the key. It cranks but won't start.
When I press the peddle down full and then try to start. It cranks and seems to want to start but then doesn't.

I checked:
- spark plugs and there is a good spark.
- for 2-3 seconds of whining of fuel pump when key is turned 3/4 prior to trying to start.
- fuel tank is full
- fuel lines seem to be pressurized?

Any idea what it could be?
Avatar
Pathfinderrs
May 22, 2007.



Check the coolant temperature sensor and do a fuel pressure check

Rasmataz
May 23, 2007.
It sounds like its your starter my was doing that for a while I would some times have to crank it like 20 times in order to get it to start so changed my starter and that seems to have done the trick

Tiny
Jayjay6888
May 29, 2007.
You might need try checking the compression in your cylinders. If you have good spark, good fuel/air, and it's cranking, then all you really have left is poor compression; or timing my be off.

Tiny
Datsunraised
Jun 2, 2007.
Its definitely NOT the starter as the engine turns over very good. Today I took it out a long drive and when I came back and stopped the truck, I was able to restart it a few times no problem. Even checked it an hour later and it started?

It wouldn't do this if the fuel pump wasn't working or the distributor wasn't working. Maybe the crank sensor? Or an injector(s) got stuck?

Tiny
Pathfinderrs
Jun 3, 2007.
It shouldn't be just one injector, because as soon as it hit a good one it would still turn over. But to make sure your getting fuel to all cylinders, disconnect your spark plugs, leaving the holes open. Then crank the car a couple of times. You should be able to smell gas coming out of all your cylinders. To then clear the gas out, reconnect your spark plugs and pull the fuse for your fuel pump. Crank again to get the gas out.

As for as the crank sensor goes, I have usually experience really rough idle also when those go out, but it's definately a viable option as well.

Tiny
Datsunraised
Jun 7, 2007.
If I hear the fuel pump and the fuel filter is ok. Then what could be the problem if fuel isn't getting to the engine?

I have still pull out the plugs and check for fuel.

I'll let you know. Thanks for the input.

Tiny
Pathfinderrs
Jun 8, 2007.
Let me take a shot at this...
spray heavy dose of starting fluid and see if the engine will turn over with combustion...if it does ..u can pretty much conclude is a fuel ctrl problem..
if it doesn't then it is a timing problem and i mean ignition,cam,injectors..whatever the hell that is not correctly timed....
okay i am gonna say something which is honest truth and repeatedly CONSTANTLY GIVING ME A HEADACHE HERE ON THIS SITE!!!!!
when u plug a wire out in open air to verify spark...IT ONLY MEAN THE MODULE/COMPUTER/POINTS WHATEVER THE HELL TURN THE IGNITION ON & OFF...DOES ANYBODY HERE KNOW THE COMPRESSURE PRESSURE REACH A FEW HUNDRED PSI INSIDE THE CHAMBER AT IDLE...SO HOW THE HELL U CAN RULE OUT THE SPARK IS NO GOOD ???? HUH HUH HUH HUH???
---NOW LISTEN!!!..ANYONE OF U OBD2 TECH HERE HEARD OF STARTER ENABLE SIGNAL ON UR OBD2 SCANNER??|?.... on a cold start if u put ur injector pulse thru a scope...ur computer get a signal as starting ..it lengenth at least 4 times on injector pulse to richen up the sytem in order to start...so if u don't have a signal and get extra fuel to kick start..guess what..it aint happening BRO!!!!!
if this is an intermediate problem on this guy..then we can pretty much rule out compression ..cuz if u have bad mechanical problem..it aint happening no matter what ...am I| right or am i right?|
service writer maybe right on coolant temp sensor ..which is another form of fuel ctrl...as a mechanic who makes a living on commission ..no time for that research and development ..spray and it don't work...then i don't have to pull scope,scanner and move on to something else ....what u think guys|?|???

heee hawwwwww


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Tiny
Kin chan
Jun 10, 2007.
Okay KC

NOW LISTEN. ANYONE OF U OBD2 TECH HERE HEARD OF STARTER ENABLE SIGNAL ON UR OBD2 SCANNER?|. On a cold start if u put ur injector pulse thru a scope. Ur computer get a signal as starting. It lengenth at least 4 times on injector pulse to richen up the sytem in order to start. So if u don't have a signal and get extra fuel to kick start. Guess what. It aint happening BRO.

Starter signal takes the place of the cold start valve to lengthen the pulse width for the initial enrichment especially in Toys. If the PCM don't see it, it will kill injectors-just like the Ne and G signals no fuel. Also the CTS will affect fuel delivery.

BTW Servicewiter was never in here

Rasmataz
Jun 10, 2007.
I changed the distributor cap, rotor, and plug wires and it started with good idle, the four times I tried. The next night I tried starting the truck and it would crank but not fire! After about 6-8 tries, I was able to start the truck. Took it for a ten minute drive, came back, turned off the engine and tried to start it and it wouldn't. I took out spark plug # 1 and it was dry, checked it for spark and there was. Did the same for spark plug #3 with the same results.

Does this sound like a fuel delivery problem now? What should I check? Senors? I have not " check engine light on" nor any codes coming up. What gives?

Tiny
Pathfinderrs
Jun 13, 2007.
In frustration brought it to the dealer, replaced the distributor also, changed the fuel pump relays around. And I still seem to have this intermittant start.

They checked everything. No codes, fuel pressure was good, sensors were fine. They weren't able to get the truck not to start. So it was hard to pinpoint. Then I get it home and it doesn't start $#%. Could any of the sensors, like coolant temperature, cranks position sensor, camshaft sensor. Work intermittantly.

When it doesn't crank and I check the plugs, their dry. So no fuel is getting to them. But why?

Thanks for any input. Boy I hope the next person can learn from my posts.

Tiny
Pathfinderrs
Jun 17, 2007.
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