Q45 help, will start but it wont rev

[drifterdevin]

Hello my buddy is having problems with his Q45, it will start up but you got to floor it to get any revs out of it, and it still won't rev very high, so what could be wrong with it?

[maxnix]

With no maintenance history, very difficult for us to discern one cause over another potential problem.

[Haitian_King]

With no maintenance history, very difficult for us to discern one cause over another potential problem.

Agreed. I don't know where to start with this problem.

How long has this been going on?

Is the engine idling rough?

I've checked Google and nothing helpful is coming up...

Please give us more info.

[unknown007]

Check the throttle cables and stuff.That's a first.If they all look in place DO NOT ADJUST!!!If one looks lose just try to adjust that one.Other than that like the rest said it could be anything.

[drifterdevin]

The engine is idling rough, so I’m thinking is a fuel or spark issue, the fuel pump has been changed, is a struggle to get it to start and when you do it bogs out. Could this bed caused by a bad injector or igniter chip?

[qship96]

It could be one or more of a dozen things- why not invest the 1 hour labor cost at your nearest dealer to have a trainrd technician diagnose the problem???? Guessing and throwing parts at it trying to figure it out yourself gets frustrating and real expensive,quick.

[Q45tech]

A competent trained technican who has worked on these for the past 19 years would tell you that he has never seen a failed ignitor chip [unless destroyed by owner or mechanic].

Just proves guessing will be time consuming and expensive.

Our average ticket on an early Q is 2 hours ~~ $170 and an equivalent in parts for a single defect.

[maxnix]

Check the throttle cables and stuff.That's a first.If they all look in place DO NOT ADJUST!!!If one looks lose just try to adjust that one.

The throttle cable has some slack designed in.

[drifterdevin]

The only problem with taking it to an infinity dealer I would have to tow it 4 hours away from here

[Infinitiguy19]

Check the Fuel pump and the control unit.

Also check the throttle body to see that it opens all the way up.

[drifterdevin]

It’s a new fuel pump,I have changed the ecu on it, the throttle butter fly dose open all the way; could a stuck injector or a bad fuel pressure regulator be causing these problems?

[maxnix]

The only problem with taking it to an infinity dealer

First, you will have to find an infinity (sic) car dealer.

[drifterdevin]

The only problem with taking it to an infinity dealer I would have to tow it 4 hours away from here

[northt]

Rent a trailer.

[Denver90Q]

Check fuel pressure, I had same thing recently.

zer...0-rpm

[Infinitiguy19]

Your can try checking the ECU codes too, even if the light is not on.

Do the A/T CHECK too.

Could be a MAF sensor too so check the board on that too.

[drifterdevin]

I have tried a new maf on it that was not the problem

[Infinitiguy19]

Hey you wern't the guy that got this car for your daughter and needed some interior parts are you?

But any ways it sound then its more like a fuel problem. You can try grounding the fuel pump to rule out the fuel pump controller, unless you replaced that when you said "I have changed the ecu on it".

[Q45tech]

An associates degree in automotive technology requires ~ 20 x 3 x 20 or 1200 hours of class room + home work.Then Nissan sends it's techs to another 160 hours of specialaization training to become the Master Technican. Each year another 40 hours on new model launch training is required.

The point is very few members here have that much education on a Q45 and as such sometimes you must bite the bullet and pay for on site expertise even if it requires a 4 hour trip to reach it.

[qship96]

I have tried a new maf on it that was not the problem

Awe, I see the 'throwing parts at it" has begun!!!! Get it into the hands of a trained professional before you waste even more money and time.

[drifterdevin]

the only reasion I'm thowing parts at for my friend is becouse I'm selling him the parts off of my Q45 that I'm parting out

[drifterdevin]

where is the fuel pump controller?

[Infinitiguy19]

Its in the trunk, but what parts is your friend buying that you need to know they work?

[drifterdevin]

my Q45 was running fine before i removed the motor to put it in my 240sx, so i'm using those parts to help him fix his Q45

[drifterdevin]

Dose the fuel pump controller look like an ecu that’s attached to the bottom of the rear deck lid?

[Infinitiguy19]

Then that just make it that much harder to diagnose, but I suggest you find some one that can do a swap right. No offence.

Yes thats the FPCU unless you have a Q45a or Q45t or something else that resembles a computer.

Look in the FSM: http://nicoclub.com/FSM/Q45

[drifterdevin]

We are not talking about my 245sx, it's a Q45 that is having these problems

[Infinitiguy19]

my Q45 was running fine before i removed the motor to put it in my 240sx, so i'm using those parts to help him fix his Q45

I thought you said you removed the motor?

If you did remove the motor then A TON CAN GO WRONG.

But if you did'nt remove the motor yet then you really need test the fuel pressure.

[drifterdevin]

no what I said is that my friend's q45 will start but wont rev up,i'm helping him out by using the parts i striped off of my Q45 that was running fine, for my 245sx swap to help him fix his Q45
Modified by drifterdevin at 12:02 AM 5/5/2009

[Infinitiguy19]

I don't know what else it could be.

I sugest you do some basic things like check the fuel pressure and ECU codes...