Hi,
03 Maxima 3.5 GL 110k miles. Spark plugs replaced at 90k.Once every 3 months or so, first thing in the morning car will crank but not start. Coughs and splutters and wants to fire. After 3-4 minutes of cranking will fire with smoke from exhaust and rough running. After a few minutes runs just fine. No starting problem when hot. No codes. Any suggestions. Al
Sounds as if the engine was flooding with fuel, as if there was a leaky injector.
Next time it happens, keep the gas pedal floored, while cranking. Doing so. will cut the injector signals, allowing for the engine to burn the already present fuel. If this improves the starting, it will confirm the leaky injector theory.
You could try the injector cleaner called SeaFoam, sold at most autoparts.
Good luck,
AS
Al Moodie wrote:
That makes a lot of sense as it felt like the engine was flooded. However most of my knowledge is from the days of carburetors, and I am familiar with flooding symtoms from carbs, lots of smooky fuel burn off after the engine fires. I didn't know an injector could leak in the on position. I will try the SeaFoam and see if that helps.
On the maxima.org forums I did a search for the problem, one poster recommended checking the the "Fuel Pressure Regulator and Pressure Dampener". Does that make any sense to you.
Thanks for your input.
Al Moodie.
If there is one leaky injector, would that flood all cylinders? If not then surely the engine would start on 5. What do you think.
Al
I had a Q45 with the same symptoms, and the problems was just the one injector.
During startup, in most vehicles, the pressure regulator is allowed to go to max pressure just to be able to suplly enough fuel to get the engine going.
In my opinion, if the pressure regulator and/or damper were defective, the problem would be there for every start up, not just once every now and then. I have been wrong before though.
Good luck,
AS
Al Moodie wrote:
Makes sense to me. I have also noticed of late that after intial cold start up in the morning the engine does not run smoothly, may be running on 5 cyl rather than 6, which would confirm our diagnosis. Once hot the engine runs smoothly.
Al.
Were the spark plugs gapped correctly? Were they torqued correctly with anti-seize applied properly?
Is the oil level too high? Does the failure occur after oil changes? after engine cleaning/washing?
Have you replaced the fuel filter?
Al Moodie wrote:
Yes they were I changed them myself at 90k miles
No.
Does the failure occur after oil changes? No
No.
No.
Al.
Typically the fuel filter being clogged manifests itself at high speed when the demand for fuel is the most.
In my Maxima, the clogged fuel filter was making the car harder to start especially in the morning; this car always starts on the first try after a very short crank. With the obstructed fuel filter, it would take a longer crank.
AS
Al Moodie wrote:
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