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Discussion Starter · #1 ·
Hi All!

A few weeks ago something changed on my '99 T4 2.5L petrol.:*

Now, instead of starting up immediately, it takes around 4 or 5 attempts to start up. The starter motor cranks over quite well but there is no sign of any ignition until the 4th or 5th attempt.

This only happens when the van has been sitting for 8 hours (overnight or while I am at work for example). If I try to start it within a couple of hours of stopping the engine then it will start straight away no worries.

I have replaced the fuel filter but this has made no difference.

Thanks as always!

Jeavon
 

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Was going to suggest the coil as cooler nights are moving in (had a coil once that worked as temp sensor, if sub 5degrees no way would it start, once the sun was on it all ok) but then saw you are a distance away.
 

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Discussion Starter · #4 ·
Update & New Information

I realize now that I have left out some critical information that, up until now, I thought was unrelated.

The first piece of critical information is that I actually have two problems and they are probably related. The first problem is that it takes 5 or 6 attempts to start up in the mornings or when I have left the car parked for 8 hours. It takes two or three attempts to start it if I have left the car parked for 2 hours. The second problem is that the car is sputtering and bouncing when during medium to hard acceleration. If I back off the acceleration a bit then it stops sputtering and bouncing.

The second piece of critical information is that I got an engine de-grease a couple of days before my problems started

The third piece of critical information is this. During the first two minutes after the engine is started it runs a little bit faster and I think this is some kind of automatic choke. During this time, while the automatic choke is on, I can accelerate hard and there is not bouncing or sputtering. During this time the engine seems to perform normally. I wish it continued to performed like after the first two minutes of running.

I have inspected the air intake, disconnected and reconnected the mass air flow sensor, and inspected the air filter box. I can advise that the air filter box seems to have two clips missing so the lid is only just sitting loosely on top of the filter. I'll have to find a way to clamp it down. Any suggestions?:

I'm hoping that with these new pieces of critical information some of you will have some more ideas for me?

Thank you all!

:*:*:*
 

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Discussion Starter · #5 ·
Update:

The problem has worsened over last few days with the onset of wet weather. The van now takes about 15 attempts to start before it fires up. The sputtering & bouncing occurs when I am accelerating, if I ease off the accelerator a bit the sputtering smooths out. The ignition also smooths out when I hit nearly 4000rpm also. Idling is pretty much fine.

A road side mechanic had a look this morning for me and he diagnosed that I have a week spark. He also says that this could explain why the engine is hard to start when cold, easy to start when hot, and harder to start when it's been raining. He said possible causes are coil (I had these problems on my old coil and on my new coil), distributor (I had these problems on old cap and new cap), rotor arm/button (I have not yet been able to replace my rotor button because the original one was factory glued).

Any tips on getting the factory glued rotor button out? Which tools to use? It seems that I will need to do it by feel, may need a mirror, and I probably need some decent lighting.

Any tips on other possible causes of "weak spark"?

Cheers!
 

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Discounting dirt/water in the fuel carb. float bowls (in the old days !) Its typical of coil , condenser , bad connection to coil , HT lead breaking down , or connection somewhere , I,ve even known the little screw caps on spark plugs vibrate loose under suppressor , if you have that type ... Is it fuel injected , or carb ?? (pardon my petrol ignorance !!)
 

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Discussion Starter · #7 ·
Hi Grey,n Grumpy,
It has electronic fuel injection.
I recently replaced coil, HT leads, plugs, petrol filter, distributor cap. Previously the fuel pump and mass air flow sensor had also been replaced. The problem has existed the whole time...more so when it's raining and especially after a engine de-grease.
The weak spark, do you think it could be caused by condenser?
Regards,
Jeavon
 

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Discussion Starter · #9 ·
Resolved!!! T:A::ILU:

I put my old coil back on and I knew straight away that that was the cause of the problems since the engine de-grease.

Now she starts immediately and hums along perfectly. One good thing about all of the troubleshooting is that I have replaced and number of parts (plugs, coil, dizzy cap, fuel filter, coil), put injector cleaner additives through, and 98 octane fuel, so it's probably running better then ever now.

So what I have learned is this. Ever since I got the van two years ago I have experiences difficult starting and sputtering when it rains. This is because my coil was getting wet! And when the mechanics did the de-grease a month or so ago they mustn't have covered the coil so guess what, it got real wet, and basically destroyed.

The main thing that I have learned is just how vulnerable the coil is in it's position on a shelf behind the left hand headlight. I think maybe water runs down the side of the bonnet and makes it's way to splash down on the coil. Plus water splashing up off the road too probably. This seems like a bad design. I would like to find out what other people have done to protect their coils. If I enclose it will it overheat?

Thanks everyone for your support while I was troubleshooting.
 
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