MY NEW 412LE PROBLEMS

Just for 411 and 412 stuff.
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Adrian
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Joined: 31st October 2004 - 12:24pm
Location: Lancashire

MY NEW 412LE PROBLEMS

Post by Adrian » 31st May 2011 - 10:15pm

As some of you may be aware, just purchased this 412le variant and love it. Only took delivery last night so after work tonight i thought i'd take her for her first spin out around the local countryside, really wish i never bothered.
Firstly, she started great tonight and ideled great. Drove about half a mile up the road and then she started developing flat spots and really struggled in the lower gears to accelerate. Pulled up, revved her a little, set off again and was much better although with plenty of flat spots in the lower gears. After a quick brew, set off back home, once more started great and ideled fine but, again not wanting to accelerate and then suddenly improves and away she went; then twice when i stopped she just died on me but did start up again straight away. Once she is in forth gear and built up speed it seems fine, just really when trying to drive slowly in the lower gears. Any ideas would be greatfully appreciated, just wish there were more aircooled fans in this area ????????????
Anyway here are some pics i took whilst i was out.
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Editor
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Joined: 10th October 2004 - 8:52pm
Location: Pensford, Bristol
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Re: MY NEW 412LE PROBLEMS

Post by Editor » 1st June 2011 - 12:01am

That's disappointing, but if it ran well when it was running well (!), it's probably nothing too major. Most likely something electrical (and there's quite a bit of that in FI) is a bit loose.

OK, a couple of likely problems that fit the symptoms.

The injector plugs (I assume it's FI) can get loose wires. This gives intermittent problems like this. The wire ends can be removed from the plug with a thin very small screwdriver to depress the tang that holds them in. Remove and slightly squeeze them to make a better connection. If you've had 2 or 3 injectors working some of the time, you would have noticed just such a problem. You could get it idling and wiggle them in turn to find if any cause it to idle worse or better - that might save a bit of time, but if one is loose, they may all be a bit that way. Don't strain the wires - some of the looms are getting a bit weak mechanically.

The other thing to suggest at this stage (keeping it simple for now!) is to check the voltage when the engine is running - I may be barking up the wrong tree as I'm not sure what sort of regulator problems you can get with an alternator, but the FI Type 3 with its generator can run badly and miss when the voltage regulator isn't allowing the voltage to rise to somewhere between 13.5V - 14V or so at medium rpm. Since yours seemed to run well at higher rpm if you could get there, that might fit the facts.
If you've a voltmeter, it's not hard to quickly check this. Use the coil 15 lead if you like, so you can manually move the acceleratot cable.
Dave.

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Lahti411
Posts: 59
Joined: 30th July 2007 - 9:34pm
Location: Lahti, Finland

Re: MY NEW 412LE PROBLEMS

Post by Lahti411 » 1st June 2011 - 7:47am

I'm not too familiar with the D-jet yet, as the car i've had for longer has twin carburetors. But i've read a lot about these as my new project has the D-jet.
I've understood that vacuum leaks can cause a lot of problems too as they will disturb the D-jets function. Change the injector seals, all vacuum hoses, head cover seals and breather cover seal.
My cars: 1972 VW 411 Variant, 1973 412 4-door sedan, 1976 Saab 99 Combi Coupé

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Adrian
Posts: 78
Joined: 31st October 2004 - 12:24pm
Location: Lancashire

Re: MY NEW 412LE PROBLEMS

Post by Adrian » 1st June 2011 - 7:50am

Editor wrote:That's disappointing, but if it ran well when it was running well (!), it's probably nothing too major. Most likely something electrical (and there's quite a bit of that in FI) is a bit loose.

OK, a couple of likely problems that fit the symptoms.

The injector plugs (I assume it's FI) can get loose wires. This gives intermittent problems like this. The wire ends can be removed from the plug with a thin very small screwdriver to depress the tang that holds them in. Remove and slightly squeeze them to make a better connection. If you've had 2 or 3 injectors working some of the time, you would have noticed just such a problem. You could get it idling and wiggle them in turn to find if any cause it to idle worse or better - that might save a bit of time, but if one is loose, they may all be a bit that way. Don't strain the wires - some of the looms are getting a bit weak mechanically.

The other thing to suggest at this stage (keeping it simple for now!) is to check the voltage when the engine is running - I may be barking up the wrong tree as I'm not sure what sort of regulator problems you can get with an alternator, but the FI Type 3 with its generator can run badly and miss when the voltage regulator isn't allowing the voltage to rise to somewhere between 13.5V - 14V or so at medium rpm. Since yours seemed to run well at higher rpm if you could get there, that might fit the facts.
If you've a voltmeter, it's not hard to quickly check this. Use the coil 15 lead if you like, so you can manually move the acceleratot cable.
Thanks, really appreciate those comments, will post the results over next few days, cheers Adrian

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davidoft
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Joined: 11th April 2012 - 1:32am

Re: MY NEW 412LE PROBLEMS

Post by davidoft » 28th February 2013 - 5:04pm

try the fuel filter

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Boardpaul
Posts: 47
Joined: 21st February 2013 - 1:42pm
Location: Mirfield

Re: MY NEW 412LE PROBLEMS

Post by Boardpaul » 2nd March 2013 - 5:00am

Btw whereabouts in lancashire?

pmacs49
Posts: 115
Joined: 24th February 2014 - 6:58pm

Re: MY NEW 412LE PROBLEMS

Post by pmacs49 » 8th May 2014 - 8:50pm

Fit a new condenser, check the points, I put the timing light on mine, no 1lead was duff and no 3, so I put a new set of leads on, change the condenser, set the points, she runs a lot quieter, responds, and starts straight away, so much for so called professional restoration companies, or qualified mechanics, this is old school stuff, you either grew up with it, or you learn fast,
Just need to get a decent fuel line from the pump, to the carbs now, and hello Mr mot man.

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Paul Hayward
Posts: 373
Joined: 24th October 2006 - 1:01am
Location: Southampton

Re: MY NEW 412LE PROBLEMS

Post by Paul Hayward » 4th October 2014 - 1:33am

really nice looking 412 that 8) ....one day if ever i get a vw again ( Just time n money)...should never of sold em all :roll: i think it will be a 412 again :D ...hope she is running well and your enjoying ;)
Paul and Kat

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