Starting

[Panthera]

I have had my injectors changed (OEM) and the inlet cleaned on my GTi and the improvements are night and day.  However, since this work was done at a VAG specialist, it is now struggling to start/catch - and the specialist now thinks its the low pressure fuel pump and fuel filter is to blame.

Anyone got any ideas why it now suddenly it is struggling to start?

[CalMac]

My ‘07 chugs into life a little bit but I expect that when I’ve got 99 in my fuel tank. Maybe 3 audible cranks before starting.

Depending on what fuel has been used throughout its life and how long since the fuel filter has been changed that might just be it.

Might be worth checking your air filter and spark plugs?

[Panthera]

I had a major service in November last year - plugs,  filters, oil and cam belt belt and water pump.  The fuel I use is Shells 99 Ron and have only used that in the 7 years of ownership apart from one tank of Shell 95 when I was in Wales a few years ago.

The car start fine when warm, just initial cold start like it’s sucking in too much air or fuel. Like it’s hunting to start.

[CalMac]

When I had my cam follower done recently at a specialist nearby, I asked if there is a problem with the way it starts and he said not really, his son’s was the same, even though it kind splutters for a second while it gets going but that seems to be pretty normal. If mine has been sat for say 5 days or so, it will *crank, crank, crank splutter, pause, splutter* then idle.

I very much doubt a worn cam follower would cause that either and replacing it on mine didn’t make for noticeably smoother cold starts.

Your specialist might be right about the lpfp being the problem but I really don’t know a sure fire way to prove it is without replacing it. A telltale sign will be it failing to prime. When you open the driver door you should be able to hear a gentle hum for about 3/4 seconds, it may do a little hum again when you turn the key to position 2.

You’ve got spark and air and idle no problem, I guess the next port of call would be the lpfp like you said.

I think a more experienced member should be able to help you out, I’m really not as familiar as I’d like to be with ea113 yet.

[GVK]

My starting has improved since I've had a few cans of Liqui moly injector cleaner through it.

Used to crank then kinda splutter into life before.

[brian_badonde]

I had the same issue for a while. Replacing the fuel filter sorted it. As the chap above said, when you open the driver's door or turn the key to position 2, you should hear the lpfp priming. Before I replaced the filter, I found priming the pump a couple of times always made it start on the first turn of the key so that I wasn't constantly cranking the starter and draining the battery.

[mjmallia]

The HPFP is a mechanical one, so needs the engine turning over to create the desired pressure....so the initial second or two it will feel a little lumpy until the engine has started......especially in the cold as fuel is obviously more combustible when hot.

Some say the LPFP can be a bit tired if the cranking goes on a little longer.

[Panthera]

I had the Cam follower done when I had the injectors and carbon clean.  What I can’t work out, why did it started fine before this work, but now it struggles. 

My original problem was at the beginning of the year with all of the old weather and just doing short journeys to work (10miles) my car was not cold starting properly - instead of idling at 1100-1200 it was 1000 rpm or Lower. Also I noticed it sounded rough - like misfiring. 

I booked the car into a VW main dealer ( opposite where I work and they found after keeping the car over night that that cylinder 1 misfired at 1000rpm and cylinder 2 at 1500-2000rpm when cold. Then when they retested it, it was fine.

And said I would need to replace injectors, coils and walnut clean. But did not advise doing any further work just yet. So I contacted the VAG specialist that I use for servicing and they said injectors and carbon clean.

The car now when started is fine, I just now have this problem. The few days after I had this work done the car struggled to start, but now even after 2.5 days of not being used it’s better, not not 100%.

  There is an Audi able hum when I open the drivers door. Not tried ignition 2 though and listened?

Would Vagcom display the values of the lpfp?

[colesey]

I had the same issue for a while. Replacing the fuel filter sorted it. As the chap above said, when you open the driver's door or turn the key to position 2, you should hear the lpfp priming. Before I replaced the filter, I found priming the pump a couple of times always made it start on the first turn of the key so that I wasn't constantly cranking the starter and draining the battery.

I, too, would recommend replacing the fuel filter with a new 6.6bar one.  It's a slightly off the radar part and pretty cheap.  Brian, thanks for evoking memories of starting my caterham!

[GreigC]

Your issue is the fuel pump (inside the tank) when you start the car it does not have enough PSI to start the car it splutters. If you turn it off and on again it will most likely start first time and run perfectly fine. When the car is left again the pressure drops in the return line causing rough start up.

[Panthera]

I think you might be right on that one GreigC.

[DurinsBane117]

Did you manage to sort this issue?

[pudding]

Your issue is the fuel pump (inside the tank) when you start the car it does not have enough PSI to start the car it splutters. If you turn it off and on again it will most likely start first time and run perfectly fine. When the car is left again the pressure drops in the return line causing rough start up.

Yup. Either that and/or the HPFP is not building pressure quickly enough from stone cold left overnight.

Fuel demands from stone cold are massive, and intake runner flap operation also needs be tip top to get a smooth start. Flap deletes need not apply.

Excessive carbon fouling can also affect cold starts as it disturbs the air flow so much, the stratified injection mode gets thrown completely out of whack.

Providing all of that and the injectors are in good order, it should start first crank and settle immediately to a smooth idle.

Mine did precisely that, even at 180K miles, because I kept on top of the maintenance  TFSIs need lots of love, back rubs, tickles and sweet nothings whispering into their ears, otherwise it's screw you pal, I'm in a grump.

[SANDEGTI]

I tend to turn the key over until it stops beeping, then start it. Not sure where I heard it from but it definitely helped. Either way, I've had pretty much everything done to mine and it will still struggle to start if it hasn't been driven for a while, primarily in the cold. I just got used to it to be honest but if it's becoming an annoyance, it could be any of these:

- Clogged Fuel Filter
- Low Fuel Pressure (FP not delivering the correct pressure to the fuel injectors)
- Fuel Injectors
- Engine Coolant Temperature Sensor (dead sensor/malfunctioning sensor will throw incorrect data to the ECU)
- Battery or Starter Motor
- Insufficient air intake

[probedb]

Thanks, also having the same issue, maintenance weekend this week unless it decides to pee it down again!