Please Help, Q45 Turned off while driving.

[knghtryde]

I've only had my Q45 for about 2 weeks now. Yesterday when I was coming home from the post office my car shut off on me on the road. It didn't just die. The RPMs slowly died down before it shut off.

It did turn on but then the RPMs slowly lowered and died again. Then it just cranked but wouldn't start. I had it towed to my appartment.

When I got the car I noticed that I could hear a really really load noise from behind the back seat as if it was coming from the Fuel Tank. So I'm guessing that It was the fuel pump. It made the noise when the ignition was on. And it was load.

The noise has completely disappeared now though.

The car is a 1990 and has the original fuel pump. I know that nissan has a problem with fuel pump failure, but I wanna know what you guys think. Could it be a bad fuel pump.

Oh and I've also only been getting about 13 mpg since I bought the car.

Please any and all imput is greatly welcome because I really need to get this car running again. Thanks.

[DAEDALUS]

I would agree it's a bad pump. Hopefully the controller didn't burn out too.

[knghtryde]

What is the controller and where do I find it?

[DAEDALUS]

http://www.nissaninfiniticlub....18148

[wlong]

Check some of the other postings on the subject. The "controller" operates the fuel pump at one of three speeds depending on the driving conditions. It is very expensive and can burn out when an aging fuel pump puts additional load on it.

Mine is located under the read deck next to the RR speaker and above the fuel tank.

Good luck

W. Long96 Q45

[Q451990]

The noise has completely disappeared now though.

That's a pretty good sign that it's dead. I'd go ahead and look for a controller.... when they die like that it typically fries the controller too.

Heath

[knghtryde]

Okay what about the fact that my car keeps turning on for about 2 or 3 seconds then slowly starts dying out.

Does that information tell me anything at all.

[Q451990]

It tells you that you're building up a little pressure from the sun warming up your gas tank... Mine did the same thing - started for two or three seconds, but no fuel. I had a Q torn down once for injector replacement and forgot to leave the gas cap loosened. The car sat in the sun for a while and pushed a gallon or two of gas down my driveway, just from the heating pressure.

Heath

[DAEDALUS]

Yeah, and if the unhooked fuel line is lower than the fuel tank, look out! It can siphon out the entire tank. I've heard stories of this happening at shops from my shop teacher. Kind of a funny thing (NEWBIE!) but dangerous too.

[Q451990]

Very true... I discovered that while replacing the fuel tubes on Q2 that were damaged by the shipper. Wasn't funny at the time, but I got a drip of gas in my eye, ran inside and rinsed it out - went back outside and immediately got another drop in the other eye!

Talk about being glad the neighbor's kids weren't nearby to expand their vocabulary.

Heath

[knghtryde]

Hey does anyone know if the 240sx Fuel Pump is compatible with the Q45 fuel pump. I have a couple brand new Walboro High Pressure Fuel pumps at home. (I build Turbo KA's on the side for extra cash) Would I be able to get one of them to fit in my Q45.

Anyone have any ideas.

[maxnix]

Anyone have any ideas.

Does buy OEM sound right?

Do the Walbros have the same mounting flange, deliver the same pressure and flow rate at the same voltages provided by the FPCU? Will they accommodate the fuel level sensor?

[knghtryde]

I don't know. That's why I asked.

[Q451990]

I've never heard of a successful aftermarket installation. I think you'd be better off just going with the OEM unit from Joe.

Heath

[QShip]

Hey does anyone know if the 240sx Fuel Pump is compatible with the Q45 fuel pump. I have a couple brand new Walboro High Pressure Fuel pumps at home. (I build Turbo KA's on the side for extra cash) Would I be able to get one of them to fit in my Q45.

Anyone have any ideas.

It can be done. You have to figure a way to bypass the fuel controller so that the pump will run at 12 volts all the time.

I was talking with 1qckser and someone else about Walboro pumps.

[Q45tech]

Then you are depending on the fuel pressure regulator to DO MORE WORK THAN DESIGNED.

What most don't consider is that there is also a fuel pulse damper in front of the rail [controlled by the air pulses in the area just after the MAF ........one of those 2 small air hoses.

The system was designed for perfection in acceleration as the 34>43.4 psi is 13% difference in flow.

Believe me they wouldn't have spent all the money for FPCU and other things if the oem method wasn't necessary........it probably added $250 to the cost of the car not an insignificant number considering it could have all been profit by just hooking the fuel pump negative terminal to the ground without the FPCU in between.

Plus I don't think you'll like the sound of the pump running wide open at idle not to mention the heat effect on the gasoline in summer from the always on 50 watt [pump] heater.

http://www.babcox.com/editorial/us/us50 ... au...pump/

The Walbro GSS341 model (also called the 255 lph HP) would be the best Walbro model for the 3000GT/Stealth................Q45! http://www.stealth316.com/2-fuelpumpguide.htm#j4

[knghtryde]

I put the oem fuel pump and found a used FPCU, just to find out once I start the car that my alternator is also fried and I need to get a new one. I'm guessing it isn't easy to replace.