Changed out humming fuel pump less than a year ago car ran fine up untill tonight when i went to start here nothing but her crancking no fire after a few attempts a noticed i didnt even hear fuel pump prime cranked fast fine wont catch do still have my old pump will try tommorrowi know someones gonna ask no its not o/e its an airtex.anyway 1994 q45 new plugs water pump fuel pump #8 injector tps dont think its on right valvecover gaskets 150000miles oh and i took my (may pop now may pop later tires off)in reference to a members post about my low pro tires on my trip to texas forgot my user name then think it was omarblackq45 sorry caps n periods not here tired thanks
does the fpcu give warning before it goes
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Q45tech
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- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Re: does the fpcu give warning before it goes (omarb45)
When you don't care enough about posting form why should some of us care to answer you.
Since you are new I'll make an exception this one time.
Electronics don't usually warn you when you grossly overdraw and exceed their rated capacity............pop......dead.
At the shop we just substitute a spare or jumper the pump to ground to crank and drive into shop. Bad pumps and fpcu along with flooding are the most common reasons to be flatbedded to a shop. This was true 15 years ago and is still true today.
Infiniti dealers always insist upon replacing pump and fpcu as a set since they have learned over the years that the one they don't change will fail soon from previous stress. A come back within 12 months is something they want to avoid.
I always carry a spare pump, oring, and fpcu when I travel out of cheap tow range. Not wanting to get stuck in podunk waiting on UPS or paying retail. I carry lots of spares: injectors, ecu, tcu.
Since you are new I'll make an exception this one time.
Electronics don't usually warn you when you grossly overdraw and exceed their rated capacity............pop......dead.
At the shop we just substitute a spare or jumper the pump to ground to crank and drive into shop. Bad pumps and fpcu along with flooding are the most common reasons to be flatbedded to a shop. This was true 15 years ago and is still true today.
Infiniti dealers always insist upon replacing pump and fpcu as a set since they have learned over the years that the one they don't change will fail soon from previous stress. A come back within 12 months is something they want to avoid.
I always carry a spare pump, oring, and fpcu when I travel out of cheap tow range. Not wanting to get stuck in podunk waiting on UPS or paying retail. I carry lots of spares: injectors, ecu, tcu.
Re: does the fpcu give warning before it goes (Q45tech)
could you read the post?then I did care anyway,fuel cap was still under pressure new fuel pump.was asking if anyone thought it was fpcu or now maybe fpr.not many g50 where im at I think ones in yard in maryland have to check.There was another post about car moving sideways over joints in the road.car does do that also now that I put on o/e tires didnt when I had 235/40/18
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yodawill2000
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- Location: Grand Prairie TEXAS
Re: does the fpcu give warning before it goes (Q45tech)
this is a forum for cars not typing.anyway car ran fine.now wont start..no hum from new fuel pump..ssssssooooooowas asking anythoughts on fpcu,or fpr?idle dropped to almost zero then picked right back up once in texas.other than water pump,fuel pump no real problems.my girl says I treat the car better than her.just want input before buying new one.can fix mechanical things not electronic.
Re: does the fpcu give warning before it goes (omarb45)
jumpered fuel pump still wont start.no burn marks on connectors,any help?lotta grazn on post no takers.dont want to scrap her,but she isnt playing fair.
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elwesso
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2007 BMW M Coupe
2007 Infiniti G35 S 6MT - Location: Indiana
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Re: does the fpcu give warning before it goes (omarb45)
when you jumped the fuel pump (grounded white wire from FPCU connector), did the fuel pump kick on?? You should have heard it much more audible since the pump was at high speed..
Its kinda tough to find a good ground back there since everything is painted, I used an alligator clip hooked to one of the screws on the speaker to jump a customers car...
Its kinda tough to find a good ground back there since everything is painted, I used an alligator clip hooked to one of the screws on the speaker to jump a customers car...
Re: does the fpcu give warning before it goes (elwesso)
Touched every piece of metal I could find pump never made a sound.Yesterday I loosened gas cap had pressure, today did same thing cap had pressure bought fuel pump from oreillys auto parts in Texas but the closest one to Delaware is in Virginia.Its not o/e could that be y its not comn on while being jumpered?(airtex).Its a shame she is a nice car,no tears on leather no dents resprayed hood (Texas) sun.My girl finally came clean and said she drove it to store and it hesited when pulling off from stop signs.could a failing fpcu take out a fuel pump?Had plans to takle driver side exaust leak but dont know now.
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Q451990
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Re: does the fpcu give warning before it goes (omarb45)
The high current draw from a worn pump kills the FPCU, not the other way around. I would replace both. New OEM pump, and a known good controller. There's no telling what you got with the O'Reilly fuel pump. Hopefully they will give you a refund.
Getting pressure when you remove the gas cap doesn't tell you much. The tank builds pressure just sitting in the sun. I had a couple of gallons spill down my driveway during my first injector/plenum job because I didn't leave the cap loose.
Now that you mention it - I recall a little hesitation/bucking before my controller failed. It was under light to moderate uphill acceleration the night before it failed. Luckily it died when I tried to start the car the next morning - not on the road.
Heath
Getting pressure when you remove the gas cap doesn't tell you much. The tank builds pressure just sitting in the sun. I had a couple of gallons spill down my driveway during my first injector/plenum job because I didn't leave the cap loose.
Now that you mention it - I recall a little hesitation/bucking before my controller failed. It was under light to moderate uphill acceleration the night before it failed. Luckily it died when I tried to start the car the next morning - not on the road.
Heath
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Q45tech
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- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Re: does the fpcu give warning before it goes (Q451990)
Every electric motor on earth slows down and draws more current WITH AGE. The commutator gets worn and oxidizes [creating more than new resistance] between the carbon brush and the copper commutator.
The carbon brush wears filling the space with carbon and copper dust which adds friction to the system and acts as a drag on the shaft. Thus the rpm drops. This drop in rpm brings the motor noise into the human hearing range [in the case of a fuel pump].
The snap and crackle you hear are tiny sparks and minature explosions from the arcing occuring!
I am very worried about US educational system when these simple facts are not understood and allow HS graduation without some minor knowledge in science.
As to advance warning one would measure [ammeter] the fuel pump fuse currrent draw and watch as it increases year over year. Normally the 15 ampere fuse sees much less than 1/2 the rating or < 7 amperes.
The carbon brush wears filling the space with carbon and copper dust which adds friction to the system and acts as a drag on the shaft. Thus the rpm drops. This drop in rpm brings the motor noise into the human hearing range [in the case of a fuel pump].
The snap and crackle you hear are tiny sparks and minature explosions from the arcing occuring!
I am very worried about US educational system when these simple facts are not understood and allow HS graduation without some minor knowledge in science.
As to advance warning one would measure [ammeter] the fuel pump fuse currrent draw and watch as it increases year over year. Normally the 15 ampere fuse sees much less than 1/2 the rating or < 7 amperes.