This has been a long term issue with my Q. Starting hot or cold is ok. However, if I start the car cold and then only let it run for a minute and then shut it down, the next time I start the car, it is hard to start and when it does fire it is obviously flooded and runs as a rich stumble. Is there a service bulletin that address's this? All I can think is that the injectors leak fuel from the previous cold start and when you start cold again the engine is getting way too much fuel.
Tim
94' Q engine flooding
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Q45tech
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1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Re: (DAEDALUS)
Designed to punish you for ABUSIVE unhealthy habits, [automotive child abuse].....why would anyone crank a cold [cold coolant] engine and not allow it to warm up?
Re: (DAEDALUS)
Any idea how difficult it is and how many shop hours I would spend to do a rail leak down check?
As for abusing my ride, I only subject the car to a quick start and shut down when I'm moving the car after my wife has parked it in a vulnerable location. I guess with new struts I should just go and enjoy a quick drive.
Tim
As for abusing my ride, I only subject the car to a quick start and shut down when I'm moving the car after my wife has parked it in a vulnerable location. I guess with new struts I should just go and enjoy a quick drive.
Tim
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Q45tech
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1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Re: (TViking)
"quick start and shut down when I'm moving the car after my wife has parked it in a vulnerable location."
My point exactly - this proceedure is EXACTLY what causes the engine to react as you described.
A no no that was warned about beginning in 1990 with the first Q. All new owners were warned not to operate in this manner!
A function of having very large capacity injectors and the batch fire [all injectors open simultaneously] at cold crank.
This type of ABUSE washes the oil from the piston rings and removes any compression from the cylinders.........dilutes oil with gasoline and seriously increases ring wear when the compression comes back.
Important to understand how the ecu uses WOT SIGNAL [at crank] to stop the batch fire process with cold coolant.
Explain to wife how her actions are destroying engine! Where she parks and the need to move then YOU not waiting for the coolant to warm up.
My point exactly - this proceedure is EXACTLY what causes the engine to react as you described.
A no no that was warned about beginning in 1990 with the first Q. All new owners were warned not to operate in this manner!
A function of having very large capacity injectors and the batch fire [all injectors open simultaneously] at cold crank.
This type of ABUSE washes the oil from the piston rings and removes any compression from the cylinders.........dilutes oil with gasoline and seriously increases ring wear when the compression comes back.
Important to understand how the ecu uses WOT SIGNAL [at crank] to stop the batch fire process with cold coolant.
Explain to wife how her actions are destroying engine! Where she parks and the need to move then YOU not waiting for the coolant to warm up.
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maxnix
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1995 Infiniti Q45t
2000 Infiniti Q45
Laying Down the Law of Cold Starts (Q45tech)
What a great public service message for the married man!
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elwesso
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Re: (911/Q45)
It clearly states in the owners manual that whenever the car is started to allow it to run for at least 2 minutes.....
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JedCoop
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Re: (elwesso)
Usually its only my wife that reads the owners manualelwesso wrote:It clearly states in the owners manual that whenever the car is started to allow it to run for at least 2 minutes.....
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Q45tech
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1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Re: (JedCoop)
Should be a 100 question test before members are allowed their first post and a 500 page mandatory to read/study tutorial to prep for it [each page with a yes no [fully read] click! Then you get a screen name! Plus your score gets posted for 6 months.
Re: (Q45tech)
I was just asking a simple question about some cold start characteristic that I have never observed in any other car. I appreciate the tech feedback but could do without the admonishments. I'm one of you...you know someone who cares about their Q. I may not know all the ins and outs of my Q and that's why I'm here. I'm a newbie..I admit it. I'm here to learn from every poster and I'm always willing to be wrong.
I fly and teach behind a number of different aircraft engines, both piston (radial) and jet and fully understand how important a proper warm up is. I recall some radials would actually have a way of diluting the engine oil with gas before a cold start to help the viscocity. The gas in the oil quickly burns off after engine start with no harm to the engine. For normal starts, most small aircraft engines have primers that inject raw fuel into the cylinder for starting. Early oil pressure is what is important. Certainly if you wash the cylinders of any oil coating that was on them from the previous run and then store the engine, you can develop corrosion because the oil coating is washed off. Lycoming cams are problematic in this regard.
So...I'm plane smart and Q stupid. I admit that it's been a few years since I read my owners manual and it does offer some tips that I had forgotten. However, I cannot find any specific reference to a "2 minute" warmup.
Tim94 Q45t
I fly and teach behind a number of different aircraft engines, both piston (radial) and jet and fully understand how important a proper warm up is. I recall some radials would actually have a way of diluting the engine oil with gas before a cold start to help the viscocity. The gas in the oil quickly burns off after engine start with no harm to the engine. For normal starts, most small aircraft engines have primers that inject raw fuel into the cylinder for starting. Early oil pressure is what is important. Certainly if you wash the cylinders of any oil coating that was on them from the previous run and then store the engine, you can develop corrosion because the oil coating is washed off. Lycoming cams are problematic in this regard.
So...I'm plane smart and Q stupid. I admit that it's been a few years since I read my owners manual and it does offer some tips that I had forgotten. However, I cannot find any specific reference to a "2 minute" warmup.
Tim94 Q45t
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Q45tech
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1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Re: (TViking)
The Q uses batch fire [all injectors open simultaneously] to preload the cylinders with fuel.........this is switched to sequential after 3-15 seconds depending on coolant temperature and a safety software timer.
When you cold crank and move a short distance, then turn off the software timer resets so the next time you crank cold the cylinders see a double shot of fuel on the already wet spark plugs.........the oil has washed from rings yielding zero compression thus no start until the rings get reoiled......unfortunately the double squirts keep coming as the ecu assumes not enough fuel to crank.......as rpm don't rise above 300 to signal the fuel normalization process.
Why you floor the accelerator with the key on but before starting [position]to set the electronic software choke which kills all fuel flow from injectors......and start the process on yesterdays fuel aready in the cylinders. You hold the accelerator WOT until the engine starts........ABSOLUTELY no pumping of pedal just WOT. It may still take a minute or 2 for the cold oil to reoil the rings [depends on oil type and viscosity and temperature].
They get towed in all the time in winter for this........flooded by a new owner [of an old 90-95Q] who was never warned by dealer to do this proceedure outlined very well in service manual.
Lexus has a similar problem [90-95] as the cold start separate injector was controlled by coolant temp and timer until 350 rpm.........but it dumps into plenum farther from cylinders and puddles there. So you may get a stall after it cranks.
Simple.
When you cold crank and move a short distance, then turn off the software timer resets so the next time you crank cold the cylinders see a double shot of fuel on the already wet spark plugs.........the oil has washed from rings yielding zero compression thus no start until the rings get reoiled......unfortunately the double squirts keep coming as the ecu assumes not enough fuel to crank.......as rpm don't rise above 300 to signal the fuel normalization process.
Why you floor the accelerator with the key on but before starting [position]to set the electronic software choke which kills all fuel flow from injectors......and start the process on yesterdays fuel aready in the cylinders. You hold the accelerator WOT until the engine starts........ABSOLUTELY no pumping of pedal just WOT. It may still take a minute or 2 for the cold oil to reoil the rings [depends on oil type and viscosity and temperature].
They get towed in all the time in winter for this........flooded by a new owner [of an old 90-95Q] who was never warned by dealer to do this proceedure outlined very well in service manual.
Lexus has a similar problem [90-95] as the cold start separate injector was controlled by coolant temp and timer until 350 rpm.........but it dumps into plenum farther from cylinders and puddles there. So you may get a stall after it cranks.
Simple.
Re: (Q45tech)
That's just the info I was looking for...thanks much for that.
Regards,Tim
Regards,Tim