dddzoomzoom

Anyone else having an issue with starting on the first try from a cold start? More often than not, I have to give it more than one try to start the car after sitting over night.

engine will turn but won’t start immediately. Sometimes will start for 2 seconds and then shut off. It always starts on the next try.

changed spark plugs and coil packs recently. new engine air filters installed also.

This improved the issue a bit.

what else to look at? Fuel pump?

JW911

Yes my first thought if also fuel pump.

AdamSanta85

Could be the high pressure fuel pump. How long has it been going on? Usually they fail quick once they start going.

Does it run fine once started?

A quality scanner should be able to see the lower pressure psi, the high pressure pump ps, and their target psi. If reference is below target, that’s likely the issue

JimEb

This was my first hunch as well. What happens is the pump motor hangs up and can't get spinning. Once it's spinning it's fine. The old trick when you suspect this is while someone's cranking the engine someone else is beating on the fuel tank with a rubber mallet. Not sure that procedure is doable on a 911, however.

dddzoomzoom

it’s been doing this since I got the car almost half year ago.

it runs fine once it starts.

However, I did notice that sometimes at slow speeds, like going through a drive through or parking lot, the car jerks a little. Not always.

Is this a DIY? I’m pretty handy and do most things myself if there’s a tutorial or guide.

I can see if my Icarsoft scanner can read out any of that information.

AdamSanta85

Yes check your Icarsoft for High Pressure Actual, and Target and same for low.

Our cars have two pumps, a low pressure in tank that feeds the high pressure, 60-80psi, and an engine driven high pressure that boosts pressure to 3000ish to feed the injectors.

When mine failed on my Land Rover, high pressure target was like 3000, and actual was same reading as low pressure target/actual, basically saying the high pressure wasn’t doing anything

If those check out, maybe try a bottle of BG 44k injector cleaner. Surprisingly, it can be pretty effective.

dddzoomzoom

thanks for the tips. I’ll check and report back. I’ll also try the fuel injector cleaner just to see if it improves. On my other cars, i usually use Techtron.

dddzoomzoom

It was the high pressure fuel pump. My Indy shop replaced it. $1200 for the pump! Sheesh. Car starts up with no hesitation now.