Help 996 shut down while driving

[911mike99]

I had little less then 1/4 tank of gas. I down shifted from 4 to 3rd gear & it stalled. Try to start & stalls after running for second. 1 hour later try to start & same thing. Runs for second & shuts down. I thought maybe a vapor lock because gas was kind of low. I did add a little gas from my Lawnmower can. Any ideals?

[SimonP5150]

When was your fuel filter last replaced? I'd start there.

[911mike99]

Not sure when filter was changed. I had the car for over 3 years & never changed it. But it ran fine up that point.

[911mike99]

I did install a cold air intake about a month ago. Could it be mass air flow sensor?

[911mike99]

Help Loren!

[texanz71]

Did you try starting it up with the MAF disconnected? That is a way to test for a bad MAF. Are you getting any OBDii codes?

[911mike99]

Did you try starting it up with the MAF disconnected? That is a way to test for a bad MAF. Are you getting any OBDii codes?

No I havnt. Should I try to? No lights came on that I seen.

[texanz71]

Yes, my first suggestion is to diagnose the MAF by unplugging the connector from the air intake and starting up the car to see how it runs.

Second, If you have an OBDii reader I would also suggest seeing if there are any fault codes present.

[911mike99]

Yes, my first suggestion is to diagnose the MAF by unplugging the connector from the air intake and starting up the car to see how it runs.

Second, If you have an OBDii reader I would also suggest seeing if there are any fault codes present.

Will it start without MAF unplugged?

[Loren]

I did install a cold air intake about a month ago. Could it be mass air flow sensor?

The car does not need the MAF to idle or run well below 4000 RPM. The MAF tells the DME the airflow at higher RPMs.

I would say step one is hook Durametric, or PST2, PIWIS to the car and see if there are faults.

[911mike99]

I do not have a code reader. Where can I pick one up?

[Loren]

Durametric.com

[wross996TT]

Sounds fuel related to me....fuel pump, fuel hose, etc... Of course if you have any faults that would be nice to know.

[RFM]

It is not very clear about what type of 996 it is, if it is a C4, fill with approx. 20 liters of fuel, i suspect that the fuel gauge is upset by several refillings with small amounts of gas. Let the fuel gauge calibrated afterwards.

[911mike99]

It is not very clear about what type of 996 it is, if it is a C4, fill with approx. 20 liters of fuel, i suspect that the fuel gauge is upset by several refillings with small amounts of gas. Let the fuel gauge calibrated afterwards.

It is a C4. And I do put small amounts of fuel in. I also hear fuel pump running when I turn the key on.

[wross996TT]

It is a C4. And I do put small amounts of fuel in. I also hear fuel pump running when I turn the key on.

If the fuel line is ruptured or came off inside the tank doesn't matter if the fuel pump is working.

[911mike99]

Unpluged MAF sensor & still no start. Cranked over for a while & started to smell gas. No what!

[Loren]

Read the codes... could be crank sensor (or many others).

[911mike99]

Can I get a code reader at Advance Autos or a similar auto part store?

[fpb111]

Before you start ripping into the car fill the tank at least 1/2 full to rule out gauge or fuel pickup problems.

If you have disconnected the battery, or had it go flat, when there was around ~1/4 tank of fuel your gauge may not be accurate.

This is because Porsche used a saddle tank in the C4 that straddles the front dif to get enough fuel capacity. The amount of fuel in the isolated section is not directly measured. It is calculated by monitoring the fuel use/mpg from the first ~3/4 tank.

[911mike99]

Before you start ripping into the car fill the tank at least 1/2 full to rule out gauge or fuel pickup problems.

If you have disconnected the battery, or had it go flat, when there was around ~1/4 tank of fuel your gauge may not be accurate.

This is because Porsche used a saddle tank in the C4 that straddles the front dif to get enough fuel capacity. The amount of fuel in the isolated section is not directly measured. It is calculated by monitoring the fuel use/mpg from the first ~3/4 tank.

Ok. I will try the gas thing when I get home today. Thanks it's worth a try

[911mike99]

Before you start ripping into the car fill the tank at least 1/2 full to rule out gauge or fuel pickup problems.

If you have disconnected the battery, or had it go flat, when there was around ~1/4 tank of fuel your gauge may not be accurate.

This is because Porsche used a saddle tank in the C4 that straddles the front dif to get enough fuel capacity. The amount of fuel in the isolated section is not directly measured. It is calculated by monitoring the fuel use/mpg from the first ~3/4 tank.

. The more I think about what you saying. You might be right. I did disconnect the battery when I put the cai on. Can't wait to get home & put gas in.

[Makulu]

Not sure if this applys with the 996 but I had this happen on my old S4, was a crank sensor

[911mike99]

And crank sensor it was! Thank You