Kiwi2turbo

Hi my 996 turbo been sitting for a while in storage. Last time I used it, it started fine and no problems. The car has done 30,000 miles and is a tiptronic. I tried to start it the other day and it wouldn’t start. The car turns over, but won’t start. Battery is good and the key works fine, although I have put a new battery in the fob. You can hear the fuel pump priming and also the throttle body when I try to start the car. I have taken 20 litres of fuel out of the car and replaced it with fresh fuel. I have taken the pill (transponder) out of the key and it won’t turn over with the transponder removed. I have had the car running on easy start. Could it be that the transponder has lost its code to the ECU? The key does allow it to turn over but it won’t start or do you think it is a fuel pressure problem. Any advice would be welcome. Cheers.

Carlo_Carrera

Have you scanned the ECU for codes via the OBD2 port?

Kiwi2turbo

Hi, yes I scanned it with my launch crp123 - no faults showing. I had a local vehicle key guy look at it, and he put his software on it and it showed no faults. I feel like it the transponder is letting the car turn over, but maybe the code has been lost to the ecu and that’s what stopping it from starting? Thanks for your reply.

Biovox

Hi, I had a similar problem with my 996 TTS with Tiptronic. Can you start the car if you move the selector from P to N? If so the Tiptronic is telling the ECU that it thinks it's in gear and thus the ECU inhibits starting. I believe all that is necessary is a small adjustment to the lever/switch sensor so the correct selection is sent to the ECU. HTH Bio

cdk4219

Probably the fuel pump or most likely in tank fuel pump hose may have ruptured. You can jump the fuel pump relay and see if you have fuel pressure at the rail. If you don’t , either the pump or hose is bad. The hose is a relatively common issue

Kiwi2turbo

Hi, just tried to start in Neutral, but made no difference. I’ve just been out looking at the car with another vehicle key expert and he thinks it’s definitely no an issue with the key. I notice when I turn the car on prior to cranking, I can hear the fuel pump prime, but also what sounds like liquid leaking coming from the fuel tank area. No visible leaks under the car or around fuel tank. So, could that be fuel coming from out of a possible broken in tank fuel hose? Thanks for your input. Cheers

Kiwi2turbo

Hi, by the way how do you jump the fuel pump relay? I was thinking about testing the pressure at the fuel filter with a fuel pressure gauge. I think, I’ve got one somewhere. The second key bloke who came, reckons the problem lies with the spark side, but I don’t think he’s right unless it’s a ecu problem, as I managed to get the car to run on easy start. The ECU is not showing any faults. Any further insight will be greatly appreciated. Cheers

s65e90

Not sure if the split hose would even throw a code. I'd check it.

Carlo_Carrera

Yes, it sounds like one of the internal feeder hoses on the fuel pump split open and is not supplying fuel down the fuel line.

How much fuel does the gauge show is in the tank? If you fill the tank to the very top it might overcome the split hose and the car will start.

theprf

The split hose happened to me - it will not throw codes. The engine just won't start.

Carlo_Carrera

Here is a thread on the hose failure.

https://rennlist.com/forums/996-gt2-...ml#post8738443

cdk4219

Filling it up won’t make any difference if it’s split, and if you can hear the pump prime, jumping the relay is useless, as the relay snd pump are doing their job.

Carlo_Carrera

Incorrect. If the split hose is submerged in fuel the pump will function well enough to pressurize the fuel lines and the car will start.

cdk4219

We are apparently not talking about the same fuel hose then. The one I am speaking of is the pressure line coming out of the top of the pump. If this one ruptures, then the fuel pump just pumps it.back into the tank causing no fuel pressure. The one I am speaking of is a rubber line with a green stripe.

Carlo_Carrera

We are talking about the same hose. If that hose is split yet submerged enough fuel can make it into the fuel line to start the car. I’ve seen it several times.