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Starts without MAF barely idles

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Old 10-16-2017, 09:42 PM
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kgorman
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Default Starts without MAF barely idles

Hoping y'all can help. I don't see this issue by searching. 2004 GT3.

- Haven't run the car in a while.
- new battery
- cranked and hard started and idled really horrible, barely running
- now won't start at al
- a couple pops from exhaust during cranking
- smells like fuel
- will start without MAF, idles horrible barely running.
- tried new MAF and let sit overnight, won't start
- tried removing O2 sensors, makes no difference
- no codes on Durametric

Any help would be awesome
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Old 10-16-2017, 11:42 PM
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jimmyrepasi
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How long since last start? Sounds like you could have some old fuel in the tank and fouled the plugs
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Old 10-16-2017, 11:44 PM
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kgorman
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Yeah, this thought did occur to me. 9 months.

Pump it out, replace filter and plugs? Anything else to test this theory?
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Old 10-17-2017, 08:48 AM
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DHI
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Originally Posted by kgorman View Post
Hoping y'all can help. I don't see this issue by searching. 2004 GT3.

- Haven't run the car in a while.
- new battery
- cranked and hard started and idled really horrible, barely running
- now won't start at al
- a couple pops from exhaust during cranking
- smells like fuel
- will start without MAF, idles horrible barely running.
- tried new MAF and let sit overnight, won't start
- tried removing O2 sensors, makes no difference
- no codes on Durametric

Any help would be awesome

I bet...
Hose on fuel pump has split open.

Pull the fuel pump and check.
This has happened to me and many others.
The fuel pump and all the hoses making up the original part has been updated.

See here and other threads as well...
https://rennlist.com/forums/996-gt2-...re-thread.html
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Old 10-17-2017, 08:53 AM
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AudiOn19s
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Originally Posted by DHI View Post
I bet...
Hose on fuel pump has split open.

Pull the fuel pump and check.
This has happened to me and many others.
The fuel pump and all the hoses making up the original part has been updated.

See here and other threads as well...
https://rennlist.com/forums/996-gt2-...re-thread.html
I thought this too except he said it smells like gas...maybe searching for something with the smell?

IF no CEL it's usually fuel related and usually this hose in question.
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Old 10-17-2017, 04:35 PM
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Default Check Fuel Pressure

Originally Posted by DHI View Post
I bet...
Hose on fuel pump has split open.

Pull the fuel pump and check....
Is it possible to check the fuel pressure externally, before going to the trouble of pulling the pump?
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Old 10-17-2017, 08:54 PM
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Macster
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Originally Posted by kgorman View Post
Yeah, this thought did occur to me. 9 months.

Pump it out, replace filter and plugs? Anything else to test this theory?
9 months is a long time for premium gas to sit around.

My limited experience is with a new (at the time 2012) Infiniti Fx35 that sat 6 months with some unknown brand of premium fuel in the tank.

After 6 months the engine started and ran ok but the engine felt flat. (I had run the engine in the 6 months it sat either by driving the car around or just letting engine idle a while with the car parked on the driveway to recharge the battery. But I never added fuel.)

Since I was not familiar with the car I just assumed the car was a dog.

Over a week or so I used the car enough to run the fuel level way down and at some point I filled the tank up with fresh premium. Afterwards the engine was transformed.

No longer a dog the car ran surprisingly well.

Maybe another 3 months of sitting would have had the engine behaving like the one in your car?

If you can't find any other explanation "bad" or old gas is a good theory.

Be sure you check the car over for any rodent damage. Too many times cars that sit for a long time and 9 months is plenty long enough make an attractive home to mice or worse. The critters gnaw wiring insulation, hoses, plastic. Scrape carpet fuzz to use for nesting.

I've seen cars with holes chewed through the radiator duct rubber, through gasoline tank vent tubes that run under the car from the tank to the engine compartment. The critter stops gnawing when it gets a face ful of gasoline fumes. I've see the engine wiring harness insulation chewed up and so on.

Look on top of the engine for rodent litter, droppings. Check on top of the under body plastic panels for litter. The critters love that area as it gives them plenty of room to move around without being exposed.

Bare patches of carpet comes from the carpet pile having been removed/plucked from the carpet backing to line the nest.
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Old 10-17-2017, 09:23 PM
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DHI
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Originally Posted by black04 View Post
Is it possible to check the fuel pressure externally, before going to the trouble of pulling the pump?

Not sure of that.
Dealer had diagnosed the problem after stumping a few in the paddock.

Pulling the pump is not difficult.
In fact maybe a flashlight can do the trick by looking down the tank porthole at the top of the track.

-David
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Old 10-17-2017, 10:20 PM
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kgorman
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Awesome replies, thx all!

I will pump out the gas, change plugs, and fuel filter. I'll first take a peek inside the tank and look for a split hose.

I'll report back!
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Old 10-17-2017, 10:21 PM
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Oh I also double triple checked the battery ground was good. No change.
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Old 10-23-2017, 10:47 PM
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Pelican delivered, hopefully will find some time this week to get at it
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Old 12-27-2017, 08:21 PM
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Update..

fuel host split in tank. Very common problem. Fixing per:
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Old 12-28-2017, 03:19 PM
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Do all 996 GT3 have the rubber hose from the factory or was there an update at some point during the production run ?
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Old 01-02-2018, 06:07 PM
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Wayne K
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I read through previous posts regarding the spilt hose. Also on 6speed online there was mention a Saab repair kit that included a u shaped hose that was a perfect fit but the link to the supplier was not good. Does anyone have the Saab part # for the correct kit?
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Old 01-08-2018, 05:29 PM
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There is a thread by nineguru (Lou) I believe. I replaced entire pump to upgraded version. Might be smarter- our cars are getting old
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