hey guys,

2000 max, auto, 190,000 KMS.

ive got a problem with starting my max (wouldnt you beleive it!)
i took it to a shop to have them look at it, the mechanic told me when key is turned on to acc for int. prime its losing fuel pressure. he blocked off the return line and it was still dropping in pressure. our first step was replacing the pump( got one for 90 bucks new figured what the hell) he was so sure it was the check valve which is built into the pump.. didnt work! im just curious on what i should look at first? blocking off the return line would eliminate the FPR wouldnt it? so injectors next? i do have a bit of hesitation at 1600 rpm (worse when cold) that is very very minor once warm but i feel thats related to my fuel issues. i know there are no fuel leaks, im not burning through gas.. im kinda stumped!

 

Here's a dumb question, did he/you replace the fuel filter?

Also, please explain your starting problem in more detail.

Not saying your mechanic is useless, but a lot of them are, and fuel system issues are not common in this car.

 

you may have a leaky injector.
if its losing pressure with the return line kinked then its NOT the pump

pull the line on the regulator and see if fuel comes out
my moneys on an injector though

 

well here is the scoop, i pulled the pump out befor repacing it orginally to check the strainer, it wasnt dirty at all but i still decided to change it anyways, when i called our local supplier ( lordco) i was told they only sold the strainer with the pump for some reason($140), which i thought was wierd.
because i thought the strainer was clean enough i ruled out that as a cause. i took it to the shop we sublet our mechanical work too (i work in a bodyshop) he t'd it off and hooked up his pressure gauge, pinched the return line and turned the key to acc. for initial prime. he said its bleeding off which brought him to the conclusion the that the check valve which is in the pump to prevent fuel from leaking back into the tank though the pump was bad . i got a new pump for 140 and he charged me 30 bucks to throw it in. thats the rundown on the strainer. so yes it was replaced.

the symptoms
key turned to acc., fuel pump primes, turn it over and it cranks for about 8 seconds befor spuddering to life. i can stop the cranking and try again if i dont let it go all 8 seconds and it starts up perfect on the second try. when its warm it will occasionally struggle as well, i also notice when my fuel is full its not as often it struggles to start. i read some other post on here where he said he could turn the key and right befor it starts cranking, his fuel pump kicks on and to wait a few seconds to finish turning the key and fires up perfectly. mine does this also. i hope this is understandable.

thanks.

 

i pulled the line off the regulator and no fuel was leaking out, so im assuming the diaphram is ok?

 

Here's where you need to go:

Stop thinking about fuel. Let it go.

Cool ? Ok great.

Now start over, and tell me precisely what is wrong with the car. does it do this intermittently or all the time, if intermittent, when cold/hot, etc.
And how long has this issue been present?

Also list recent repairs, especially anything pertaining to starting system. (battery/alt/cables/charger/head unit/amp install, etc)

 

I will try and explain this the best I can.

I bought this max back in 2011 with 140,000 KMS on her. I did not notice it in the beginning (because my gas was kept full). After a month of owning it I started to notice the struggle with starting noticing the struggling starts.

Cold starts were delayed, it would crank anywhere from 5-8 seconds then hiccup ( almost seems to be a very faint intake pop but thats a maybe) and start. idle seems to be fine once running( 1300-1400 iirc and lowers once warm). If its cold and i turn it over knowing its not going to start and stop, i hear the fuel pump prime again and it fires right up perfectly with no hiccup.

Warm starts are different, it will turn over alot faster but it will have low bouncing idle and run rough for 2-3 seconds then completley stop and run fine.

Starting it right after turning it off, hot or cold, it starts perfectly, cranks once and fires right up.

I notice that when my gas tank is fuller than 3/4 its less the often it will struggle to start. It happens almost every time cold if its less than the 3/4 full mark, and still happens when above 3/4 but not nearly as often. I dont know how this plays a role in the starting issue.

I can get it to start perfectly everytime cold or hot if I turn the key and right befor it cranks I hear my fuel pump run, give it two seconds befor I finish turning the key over it will fire right up.

Im really leaning on it being a fuel issue because of that reason. the fuel pump isnt holding the pressure after priming, and if I do the above mentioned, im pushing pressure back into the fuel system. If its being started when cold, and i let the car turn over knowing its not going to start and let it crank once and stop, i hear the fuel pump re prime and it fires up perfectly on the second try.

Things i have done for this problem and what i felt was good to do for maint.

pump and strainer
motovac fuel system cleaner
intake plenum gasket and inspected for cracks
pcv valve
smoke test for any other leaks (none found)
replaced plugs with iridiums
new CTS
new MAF
new TPS and properly set
ecm is up to date
idle relearn
fuel mapping reset
inspected fuel lines for kinks
new battery
new TCM (y904)
on top of oil changes (use synthetic)
cleaned TB and IACV
cleaned CPS and CKPS ( BOTH) which actually made a difference for a week.

No codes at all, and I havent really had any major problems with this car, other than having the NATS antenna fail on me, I actually thought maybe that was the issue the whole time, something to do with the key and the NATS antenna, but it didnt fix the starting issue. 700 bucks later for a tow, new key, NATS antenna and reprogramming, still there..

 

Excellent follow up post!! You're on the right track, sorry to hear you've replaced so much without results though.

Just to verify, none of these parts/changes made any difference in starting? Correct?

There's a couple things that you should have done right off the hop. Starting issue always = a proper starting/charging system inspection.
This includes load testing battery, alternator output inspection with checks for voltage ripple, starter draw test, cranking voltage/amperage tests, and a full visual inspection of all components.

I understand thinking this is unrelated, but anytime you have a starting issue you need to check it. It seems unlikely at first, but this could be something as simple as a bad/loose connection.

In either case have you read through the FSM for this issue, followed the work charts, done the proper diagnostic procedures, etc?

http://www.nicoclub.com/FSM/maxima/2001/

First step is confirming the fuel pressure was checked properly and retesting




And don't rule out those CKPS/CPS sensors just because you cleaned them, that means squat. Though it's likely a CPS not a CKPS otherwise it would stall the engine out or not allow to start at all.

 

yes, none changed the issue even the slightest bit. lots of what was listed i was happy doing/replacing even though it didnt fix my issue. i have replaced the battery as stated and load tested the alt. i have visually inspected + and - leads, and even added a ground from the - battery post to trans. i will read over the fsm and in the next few days try and perform the fuel pressure check myself. i was leaning towards a cps as well if it isnt fuel related. im off on holidays for a few days and all my tools/guages/multimeters are at work.

thanks for pointing me in the right direction!

 

NP dude just beware pre-conceived ideas (fuel issue), stay focussed on proper diagnostic steps and don't jump around. Follow steps to precision and you'll find your problem. When you have something stuck in your head it's easy to disregard other potential issues, or make other things point to what you initially suspected.

 

so its definatley fuel related, took it to a friend who hooked up his FP guage. its bleeding back, i would think if it was a fuel pressure reg. it would not be bleeding back into the tank if the return line was blocked correct? but rather be a problem with the pump, or injectors and damper?what is the full function of a fuel damper? could the diaphram be stuck open? i do notice some pulsation (like hitting gentle waves in a boat) when its cold at low rpm that somewhat dissapears when warm, and it is supposed to prevent those "fuel waves" and could also be the reason why the fuel pressure seems ok when running, because the pump is constanly running rathern than building pressure for it to start then shutting off allowing bleed back?, maybe im feeling those because the diaphram isnt cushioning the pusles cuz its stuck open? being that 5.5 gens do not have a damper, but instead use a inline fuel filter that allows travel one way, im assuming a damper would only allow fuel to travel one way. if it was stuck open it could allow the fuel to travel back into the tank correct?

from what i just read about the fuel damper, it has a diaphram that is supposed to stop the pulsation of fuel that the injectors cause, its like a shock absorber.

i did read a post about a guy who had the exact same problems, turned out it was his FPR, but thats a 100 dollar gamble and im really leaning on a damper if my theory is correct.

thanks again

 

forgot to mention.. we allowed the pressure to build and blocked off the feeding and return line and pressure held, so i dont beleive its a bad injector. i really hope someone replys to this who can agree with my theory so i can go and get a new damper and be done with this lol, i looked online and they are pricey, but ill go to a wrecker and pick one up, if this is my problem, looking at the pictures the damper runs from the rail all the way to the firewall. there is a disconnect spot located right under the FPR regulator, would it be wise to remove the whole assembly or could i get away with un bolting it and just replacing that upper portion?

 

I had a similar problem last week. on our 2002 it would start but sputter after 10 seconds. I thought I could chk the FP like other cars but Maxima is different.
On a hunch I just replaced the Pump and strainer but problem was still there with no codes. There is no "in line" fuel Filter, Pressure Regulator, or guage connector. The regulator and Filter are built in the pump assy. You can replace the filter with a Beck Arnley or a Nissan. Not to be confused with strainer. The regulator is not for sale in any Nissan parts books I have looked at.

For me it turned out to be MAF sensor.
http://forums.maxima.org/5th-generat...y-running.html.

I had same symptoms and if I unplugged the MAF it would now run but not over 2000 rpm.

I was able to hook up a pressure guage with a hose/Tyrap and a guage to the pump outlet while disconnected and got 43#. I also saw fuel rail adapters that you can use to check pump.

http://www.ebay.com/itm/160660531818...WAX:IT&vxp=mtr

A leaky injector would lose pressure and maybe make it hard to start but it would probably run ok.

 

you had different symptoms than me.

also the 5th gen and 5.5 gen are totally different, i am a bit confused because above you put 02 and your link says 01.

plus i replaced my MAF, and i know it isnt my injectors.

but thanks.

 

Did you do the procedure starting on EC-619 for checking fuel pump?

I know there is such a fuel damper but I have no info on it, do you? If so post/link it.

I can't find a scematic of the fuel system in this car via a quick search so if you found that also post/link it.

 

The link I added was from another guy with a 2001 with a MAF problem.

The only difference I know between 01 and 02 is the MAF sensor and you can use a 01 Maf sensor on a 02 with the 02 Thermistor.

OOps I take that back as I looked at a diagram for your 00. You have the pressure reg on the rail and a return hose.

That should be easier to diagnose that the later model. If you have a FP connector on the rail you should get a FP guage to watch what it does as you drive.

I would check FP but I would use the fuel rail adapter instead of cutting the fuel line and adding a T junction.

 

i dont get it.. fuel pump was replaced... but with the return line kinked its still bleeding back through the feed line..with the feed line and return line blocked its holding pressure... im stumped. there is no leak so its obviously losing pressure threw the feed line and i highly doubt the check valve in the new pump is also faulty.. but there is no where else for it to go...

 

Put a regulator on it.

Junkyard, maybe.

 

i can grab one from a junk yard.. 100 bucks though..i just dont get it.. ruturn line blocked, it still loses pressure.. both feed and return blocked its not.. do u think its a better idea to try and throw a inline check valve on the feed line? i can find something that works, im going to go that route then ill replace the FPR

 

replaced F.P.R. no go.... sigh

im thinking i should just drive it off a cliff..with me in it...

 

Regulator is the mechanical part so it made sense.

Did you ever find fuel schematic

And I'm still not convinced this is even a fuel issue because I haven't heard 1 test that proves there's anything wrong.

I understand what you're saying about 'bleed back' but who says that's not normal? Know what I'm saying?

 

User Name 001,

I have a 2002 that is acting almost exactly like yours. I have had it to the edge of the cliff, but realized I had somewhere to be...!

Did you ever figure this out? I was about to go out and try the Idle Relearn and a load of other ECU type reset sequences, but I think you saved me the trouble.

I was aiming at the fuel rail that has the FPR built in on my Max...thinking that is not the case based off of the thread.

If you have any ideas, I would appreciate...especially if you fixed yours.

Thansk,
JB

 

john: The fuel system on the 2002/2003 Maxima is different. The two cannot be compared.

 

Username:

Because this is bumped I'm not sure if you ever figured this out, but I'd put a couple pennies on your issue being a bad clamp/O-Ring at the pump.

This allows air to be pulled in from the feed line which would cause this problem