Intermittent Start Problem - Help!

[ndxturbo]

Hi there, this is my first post so if this is in the wrong section then apologies. Also please excuse my poor terminology lol

Anyway, last month I purchased a GTi '99, however, since owning it, on a couple of occasions the engine has taken longer to start than I would expect it to. For example, I could leave the car for 5 hours, come back, turn the key to start the engine and it will struggle for a couple of seconds before roaring to life. Sometimes I've turned the key to fire the engine, let the key spring back to the position it is when the engine is started and its struggled for a few seconds before not starting all together. Although, when this happens, if I go to start it again straight away it will just fire up with no problem at all. Last week I left the car for about 3 days and when I went to start it I had to hold the key (in the position when you start the engine) for about 3-4 seconds before the engine fired up, and again, when I went to start the engine again after that it fired up no problem. Took it to a garage last week and he said it was the starter motor, so got that replaced. He also recommended that the spark plugs should be changed.

But when I went to drive home from work the other day I noticed it hesitated to start again (only for a split second longer than I feel it should, fuel light was on this time if that would make a difference). I've taken it to another garage this week, he checked the battery and said it was fine. I've left it with them for a few days to see if this problem happens when they go to start it. I will also get them to change the spark plugs before I get it back off them.

Just wondering if anyone has any idea what might be causing this rather annoying problem?? Like I said, if it hesitates for a few seconds or doesn't start as "cleanly" as it should first time, when I got to start it immediately after it will fire up like it should.

Any help is much appreciated!!

Cheers

[barrym381]

have it scanned for fault codes before spending money on it 

[matty james]

sounds like a problem i had a while ago,then my engine started to spluttter on idle in traffic ,then it wouldnt start at all soon after .was fuel pump gradually giving up .when your fuel lite is on the pump has to work that bit harder as well .will not throw up a fault code if its the pump ,  pumps are easy to change though .hope this helps a little maybe 

[ndxturbo]

I forgot to mention that once the engine is running it runs completely fine, no strange noises or splutters etc the problem only occurs on start up. Most of the research I have done seems to points towards something fuel related if the battery, starter etc is fine. Inevitably I think I will have to get it scanned though but thats not cheap either lol

Thanks for quick reply guys, anyone else with suggests would be great!!

[barrym381]

see if there is a member near you that will scan it  my guess would be temp sensor

[matty james]

engine didnt start spluttering until a good week after the poor start up problems started . do you get a constant whinig noise from your pump ?

[MoMartin]

When you say that it doesn't start properly for a few seconds then it worked, are you sure that it isn't just because the fuel pump hadn't primed? Because I have turn the ignition on before I fully turn the car on otherwise it struggles to start. If not I would try cleaning the throttle body if I was you.

[ndxturbo]

When you say that it doesn't start properly for a few seconds then it worked, are you sure that it isn't just because the fuel pump hadn't primed? Because I have turn the ignition on before I fully turn the car on otherwise it struggles to start. If not I would try cleaning the throttle body if I was you.

When I turn the ignition I hear a noise coming from the driver side which I'm guessing is the fuel pump priming? waiting for this noise to happen or putting the key in and trying to start it immediately seems to make no difference as whether it will start sluggish or not.

engine didnt start spluttering until a good week after the poor start up problems started . do you get a constant whinig noise from your pump ?

the engine only "spluttters" once I turn the key to start the engine, then it runs perfectly to my knowledge. As I said before, when I let the car sit for 3 days last week I had to hold the key in the "start" position for about 3-4 seconds before the car started. I drove it to the gym, came back to the car in an hours time and it started perfectly.

see if there is a member near you that will scan it  my guess would be temp sensor

Funny you mention that actually, near where the starter motor is, there is a bunch of wires and one of them had completely broken. When I took it to the first garage he said it might be affecting the temperature readings. He supposedly fixed this wire along with replacing the starter motor.

I'm going to go back and pick the car up tomorrow from the garage i've left it for the last two days and see if the problem has repeated on him. If it hasn't, then I'm going to have to try get it on video to show them what it's actually doing.....

Thank you for all your suggestions so far!

[Oblivion204]

The symptoms you're describing are identical to those of what's just happened to me.

I had my car in a garage for the past 3 days and he couldn't find a fault. The suggestion was to replace all 4 injectors and replace the wiring loom for an upgrade as the current one runs through the rocker cover. I looked into this and although it's a common problem I spoke with a specialist at the vw garage who states that if it was a problem with the injectors I would certainly know about it. They either work or don't, there is no in-between. To replace would cost £2200  .....yeah right,,,let me check the back of my sofa..not.

Specialist kindly looked into it for me for free and said my TDI along with all diesels often collect water from the tank. His suggestion I could fix myself turned up trumps.

1) replace the fuel filter. I got mine from Halfords for £18, took me 5 mins to replace.
2) replace the brake pedal switch to the new green upgraded version. Simple to replace, undo 3 screws housing cover to brake pedal, remove plastic surround. Turn the current switch counter clockwise and unplug. Plug in new one, no need to hold or press the pedal. The old ones are faulty on and off which when the engine is warm seems to drop the current flowing to the starter motor, it also turns off your brake lights when they die.

I did the above and my car runs so smooth now it's like I just got it from the forecourt brand new.
Costs £18 new fuel filter
£13 for new brake switch

Ideally with possible water still left in my tank I need to now syphone the fuel out, clean and replace. This can be done without the need for a new part.

You can't go wrong with trying the above. For the cost of what £31 total and maybe twenty minutes of your own labour to try this you may be surprised at the outcome. Just don't let the car fuel run too low until you can clean the tank (which lies behind the drivers seat in the rear passenger) if you have been hearing that low pitch noise coming from there when trying to start this is the pump trying its hardest to suck up the fuel. New fuel filter will resolve that straight away. Good luck as it worked perfectly for me

[ndxturbo]

The symptoms you're describing are identical to those of what's just happened to me.

I had my car in a garage for the past 3 days and he couldn't find a fault. The suggestion was to replace all 4 injectors and replace the wiring loom for an upgrade as the current one runs through the rocker cover. I looked into this and although it's a common problem I spoke with a specialist at the vw garage who states that if it was a problem with the injectors I would certainly know about it. They either work or don't, there is no in-between. To replace would cost £2200  .....yeah right,,,let me check the back of my sofa..not.

Specialist kindly looked into it for me for free and said my TDI along with all diesels often collect water from the tank. His suggestion I could fix myself turned up trumps.

1) replace the fuel filter. I got mine from Halfords for £18, took me 5 mins to replace.
2) replace the brake pedal switch to the new green upgraded version. Simple to replace, undo 3 screws housing cover to brake pedal, remove plastic surround. Turn the current switch counter clockwise and unplug. Plug in new one, no need to hold or press the pedal. The old ones are faulty on and off which when the engine is warm seems to drop the current flowing to the starter motor, it also turns off your brake lights when they die.

I did the above and my car runs so smooth now it's like I just got it from the forecourt brand new.
Costs £18 new fuel filter
£13 for new brake switch

Ideally with possible water still left in my tank I need to now syphone the fuel out, clean and replace. This can be done without the need for a new part.

You can't go wrong with trying the above. For the cost of what £31 total and maybe twenty minutes of your own labour to try this you may be surprised at the outcome. Just don't let the car fuel run too low until you can clean the tank (which lies behind the drivers seat in the rear passenger) if you have been hearing that low pitch noise coming from there when trying to start this is the pump trying its hardest to suck up the fuel. New fuel filter will resolve that straight away. Good luck as it worked perfectly for me

Thanks for the suggestion. Changing the fuel filter was definitely on the agenda because if it is a fuel problem then changing that can't do any harm, and fingers crossed it might even solve it.

However, on Saturday I took it to a garage and he plugged it into the machine (for free :O) and it gave him two fault codes. One of them he said was to do with the battery but he didn't seem too concerned by this, and the other was an ECU fault, which when he looked it up it was to do with the immobiliser. So, the next step he said was to  get it booked in and they'll get an auto electrician to come and investigate it further. I'm pretty sure this problem is directly related to how long the car has been sat for though, and I don't know if an immobilser would cause this?