g50 fuel pump question

Ok,for all you g50 owners. I have been reading up on q45.org and the vh45.org about the fuel pump hummin b4 it goes out. I dunno if mine is humming or if this is the normal whirring of the fuel pump. I'm use to cars with very audible pumps.

well i replaced mine yesterday. it was starting to fail. when we got it out we tested it wit some voltage tester or something and it hummed for like 3 times the foruth time it completely went out. so i would say the hummin is signs of it going out soon.

Yeah I've had the car only a few weeks,and been giving it the much needed attention it hasn't had. I'm just going to go ahead and replace the pump this payday to eliminate all possibilities.

Yea if you hear any audible hum from the trunk area thats a good sign to replace it before it fries your fuel pump controller when it decides to go out.

Yeah,I can barley hear a hum at a stop with the radio off so I didn't know if the pump is suppose to be completly silent or what,but I'll change it out and se what the new one sounds like,but after 180k I'm sure it's bout time to change it.

yea that fuel module thing is expensive like 500+ bucks. and pump was like 280, i just rigged up a titan one i had laying around:biggthumpup:

So the Titan one worked ok?

yea it worked fine...........but i should of listened to the infinti dealership bout the control module. this new pump went out. they had said if the pump messed up it could of messed up the module, and when puttin a new pump the messed up module would ruin the new pump in like 2 days. my car is now doin the same problems again. now i need another pump and module

Oh daym! So if the pump goes out completly,the fpcu needs to be replaced as well?

not necessarily but if it does go out you have a higher chance of ruining it.  I didn't change my pump till the hum was annoying loud (probably got lucky).  If it does go out just open up the module which is right near the pump and look for fried connections or desoldered circuits.  If anything is messed up be prepared to buy a new one from Infiniti for around $500.  Remember preventive maintainance will save your ass on such on old car.

Yeah,that's exactly what I'm doing now,a shizz load of preventative maintenance ang neglative maint. It's consuming my mod money,but I'd rather have a nice running q than a nice looking q that don't run.

Ok,here's the verdict. Put new pump in yuesterday and as fas as the noise from the trunk..............BIG differnce. Only hear a short wirr when the fuel system is being pressurized b4 startup and the complete silence after that. Drove to work this morning with noprobs at all but I got around the corner from my job coming home and it acted like it was choking and almost stalled 3 times. I finally limp home 20 miles and by that time all I could smell was melting solder. I pop out the fpcu to find the solder has melted on the ground pin. So I just finished up the NICO jumper and resolder fix and drove 30 miles and the fpcu didn't even get warm and no sputtering.

wow thats some bad luck!  glad you see an improvement!

Yeah,it seems like it'll do fine in the mornings now but act really shiddy when it's time to come home. Today it stumbled and acted like it didn't want to downshift or upshift so I did it manually and it drove fine once I got it over 40mph it was like a rocket. I did the fpcu by-pass just to see how it ran and no difference. Going to clean the plenum and tb tonite and see what happens. Prolly cut the tranny lines off the radiator and the filter looking thing and put external cooler to eliminate the posibility of fluid blockage somewhere.

oh yea tranny cooler is a MUST for these cars

Most deffinatley! I put aftremarket tranny coolers on every automagic vehicle I get. I have two on my track crx. One small one on each side of the bumpers in the fog light/brake duct holes.

Well I drove the Q to work this morning and acts like it was starving for fuel and ddid want to uppshift again. I know the only codes I'm gettin is bad number 5 injector. Can 1 bad injector cause this much trouble?:pat:

Yes, 1 injector will make for an irritating ride.

Off topic, I cleaned my MAF, intake tube, and throttle body ([URL="http://q45.org/techhelp.html"]Q45.org[/URL]) and it made a noticable difference in idle and light throttle response.  Before I sprayed the MAF, it looked really clean and I was already thinking, "Its still clean, the spray isn't gonna do anything".  After cleaning though, I'm a believer.  Next is the BG44K.

G/L with your fuel problem.

Yeah,everything that you did I have done also by reading up on q45.org. I have 2 MAFs that I have generously cleaned and on one soaked a q-tip in glead and removed more builup from the sensor element and te resistor in front of it. After that deteail I used cotton balls soaked in the clear to clean the screen and the rest of the housing inside and out. I did notice a good difference as well as emptying bout a can and half cleaning the throttle body and what I could reach inside the plenum,made a huge difference.

The fuel issue has been isolated to the fpcu and the car unwanting to shift is also tied into that. The diodes for acceleration are dying wich is causing fuel starvation under partial throttle untill I floor it and the the pump cathes up and normal driving is resumed. I did the fpcu by-pass to gound and it is a night and day differnece.

Does the g50 only have the fpcu with the 3 stage voltage outputs verses other q45s?

question how do you guys get the control module out??? i saw one at the junk yard and saw only way to get it out is too yank out the rear interior stuff and it seemed all broken i don't wanna do that.

That is the only way to remove it is by taking off the read deck cover and peeling away some of the sound damper material to expose the 2 10mm bolt heads the the unit can be romved from the trunk area.

Ok,so I got the fuel issue fixed after I ripped the band-aid off the situation. Now I have a completly new problem that causing the car not to shift. Occasional sticking brakes with super stiff pedal while driving,now WTF!