car shuts down after start

370Fan2000

So sometimes my car turns off immediately after turning it on. Like it can't hold the revs. It has no problem starting. It starts and then when the revs are coming back down, they just go low, it sputters for less than a second, and then it shuts down.

This happens until i turn it on and give it gas, then it will stay on. Sometimes giving it gas doesn't work as in it stays on while I'm giving it gas, but as soon as I let go of the gas, it will turn off.

Any ideas? I've tried searching but no luck. I also have no mods.

DEpointfive0

You have an intake leak

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370Fan2000

How do I check/fix this? How could this happen with such a new car? Btw, there are no codes being thrown.

Thanks for the help

DEpointfive0

Vibration?
Are you the original owner? If not, maybe the guy before you had an intake and didn't tighten the stock system enough


To check, TECHNICALLY you'd have to get a smoke machine
Instead, open the hood, look at the intakes and jiggle to see if any vacuum lines or anything is loose, then tighten it

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370Fan2000

There is no vibration. I bought the car with 16 k miles. The other dude assured me there were no mods, however, I cant know for sure since it was stock when I got it.

I took a quick look and did not see anything weird.

I've had it until 29k miles and I had not had this problem until 2 weeks ago. I also have one of those odb scanners I can possibly get some intake info from there if anyone is willing to explain/guide me as to which sensors I should be looking at.

ChipsWithDips

Smoke tester is the best way to check for leaks. Another option if you don't have access to smoke tester is to take a propane torch with a small hose connected and with the gas flowing (don't light the torch ) pass the hose end over various potential leak points. If the idle changes then it is sucking in propane at that point. Can also use a can of starter fluid, but this is even less precise.

There are a lot of things that can cause a vacuum leak, assuming that is the issue.

If you have a vacuum gauge you can check what it when your car is idling and compare to whatever normal value (i think it should be 20 inHg or more, not sure exact value). Someone with a normal running car might be able to test for you.

Vacuum hose leaks: visually inspect all the vacuum lines attached to the intake manifold for damage: cuts, cracks, loose connections.
PCV valve could be malfunctioning
EGR valve could be stuck open
Brake booster: If pumping brakes affects idle then it could be a leak on the brake booster hose or brake booster diaphragm.
gaskets/mating points between throttle body and manifold, intake hoses

I think a faulty EVAP solenoid could also cause a leak.

With an OBD scanner you should be able to check what your fuel trims are, if there is a leak it should force more fuel to even out AFRs, so you will see positive fuel trim. You could also try taking a look at AFRs directly.

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370Fan2000

Thanks for the help.

I'll look into it when I get back from out of state and report back.

Cmike2780

Just throwing it out there, but it could also be the MAF sensor(s). I would assume it would throw a code though. The previous owner may have had mods on the car and returned it back to stock.

As a precaution, I'd double check the oil level. A few early Z's built before 5/10/2010 had oil consumption issues. It doesn't sound like this is the case, but it doesn't hurt to check.

Your car is still under warranty. I'd bring it to the dealer and let them figure it out. You shouldn't have to pay a dime out of pocket, especially if there are no mods to the car.

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370Fan2000

Thanks for the input. I did check the oil and there was no consumption. It's still good.

Do you know if this would be covered under the Powertrain warranty?
My car is a 2010 and was bought in November 2009, so I fear the full warranty is done.

fuct

i had the exact same symptoms. it was a bad fuel pump. covered under the bumper to bumper warranty.

best of luck!

370Fan2000

I'm so glad you chimed in!. However, I'm now afraid I'll have to pay or do the repairs myself.

I'll try and find to see if there is any way I can diagnose this for sure.

fuct

why would you have to pay? its covered under warranty. unless youve modified something fuel related.....

they hooked my car up to the dignostic consult machine (2 hr/$250) and it said the pump was broken......

DEpointfive0

Hey, have you seen my thread on the car starting?

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Cmike2780

It's 3 year/36k. The 5 year powertrain warranty is bit trickier with what is actually covered. I'd double check if the bumper to bumper is active. Some dealers are a little forgiving on the date and look at the mileage. In any case, I'd bring it in. It doesn't hurt to ask the dealership. I doubt a fuel pump is going to be covered under the power train warranty though.

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fuct

i took my 2010 in at 48k miles. bought car new june 30th 2010. fuel pump, work, and tow to dealership covered under warranty......

just sayin'


fuel pump went out