Hey. In the last week I have been having trouble starting the car. Doesn't matter how long it's been sitting (half an hour or overnight.) Doesn't matter how much gas is in the tank (full tank, half tank, almost empty.)

It turns over fine, but takes like two seconds to finally catch. I don't hear the fuel pump making any unusual noises (just the normal start-up whine.) But the hesitation makes me think it's a fuel delivery problem.

Could my fuel pump be secretly crapping out? FPR? Maybe some pressure valve that's not maintaining the fuel pressure when I shut it off?

Any help would be appreciated.
TOM

 

I would do this: One morning jump start the car, just so you know it's not an underpowered battery. Another morning take a hammer to the solenoid on the starter (it's brass looking) so it's not the starter. Next put some fuel cleaner in your tank to clean your jets. Then take out and replace your fuel filter. If that isn't it replace your plugs.

Very rarely it is anything else. Fuel pump goes your car wont start and all and you will just here the relay in the fuel tank when you try to start.

Most maximas with lots of miles have some problems starting cold. After it starts you should be good to go during the day. Meaning starts on first try.

 

Assuming you have a fairly fresh air filter,fuel filter and spark plugs, I'd clean the IACV (idle air control valve). This is an electronic valving assembly and metering block on the the throttle body that meters in idle air when the throttle plate is closed (normal starting position). The procedure is explained in the 4th Gen FAQs. I completely disassembled and cleaned mine, with carb cleaner last weekend and it made a world of difference for off idle performance and faster starting. Although I didn't have a hard starting problem before the cleaning. As mentioned I took mine completely apart and separated and cleaned all the valves and metering block which is much more thorough than the procedure on the FAQs page.You'll be surprised at how much carbon builds up in these components from PCV gasses and such. The cleaning assembly and reassembly took about an hour.

 

I'm at 73k right now. All of the normal maintenance items were resolved at the 60k service - plugs, wires, all the filters, PCV, flush & fill, etc. Previously I replaced the battery so I'm sure it's not a juice issue. I figured fuel delivery because the thing cranks like hell but just won't start - kind of how it acts when I'm down to zero on gas.

But maybe the IACV is the culprit. Also, I'm wondering if my PCV valve is junk. Right after the tune-up, I started having this occasional hesitation problem when my RPM's would dip to 400-500 as I was down-shifting or stopping at a light. Makes a smooth start almost impossible. If both of those issues are happening simultaneously, they could cause a hesitation at start-up.

I think I'll replace the PCV again and tear apart the IACV. It can only help. Might as well do the TB cleaning too. What did you use to get the build-up off all the IACV parts, carb cleaner?

Anyway, thanks for the suggestion. Welcome to the ORG.

Ciao,
TOM

 

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Originally Posted by sweetdaddy
Assuming you have a fairly fresh air filter,fuel filter and spark plugs, I'd clean the IACV (idle air control valve). This is an electronic valving assembly and metering block on the the throttle body that meters in idle air when the throttle plate is closed (normal starting position). The procedure is explained in the 4th Gen FAQs. I completely disassembled and cleaned mine, with carb cleaner last weekend and it made a world of difference for off idle performance and faster starting. Although I didn't have a hard starting problem before the cleaning. As mentioned I took mine completely apart and separated and cleaned all the valves and metering block which is much more thorough than the procedure on the FAQs page.You'll be surprised at how much carbon builds up in these components from PCV gasses and such. The cleaning assembly and reassembly took about an hour.
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I'm at 73k right now. All of the normal maintenance items were resolved at the 60k service - plugs, wires, all the filters, PCV, flush & fill, etc. Previously I replaced the battery so I'm sure it's not a juice issue. I figured fuel delivery because the thing cranks like hell but just won't start - kind of how it acts when I'm down to zero on gas.

But maybe the IACV is the culprit. Also, I'm wondering if my PCV valve is junk. Right after the tune-up, I started having this occasional hesitation problem when my RPM's would dip to 400-500 as I was down-shifting or stopping at a light. Makes a smooth start almost impossible. If both of those issues are happening simultaneously, they could cause a hesitation at start-up.

I think I'll replace the PCV again and tear apart the IACV. It can only help. Might as well do the TB cleaning too. What did you use to get the build-up off all the IACV parts, carb cleaner?

Anyway, thanks for the suggestion. Welcome to the ORG.

Ciao,


I used some super cheap carb cleaner from Wal Mart, think it was called Chem Tool or something like that. I've used Gumout and 3M carburetor cleaner in the past and don't really think there is a difference. The ingredients of the Chem Tool stuff listed Toluene and Xylene so I was satisfied it had crud cutting potential.

On another note, the main electronic component of the IACV, is some kind of motor or solenoid that has cone with a vortex pattern on it. This vortex patterning trapped carbon particles (small chunks!) that I carefully removed with a dental pick. Used a soft tooth brush and cotton Q-tips for the other parts.

Thnaks for the welcome to the forum.
SD