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General Information => Troubleshooting => Topic started by: burn_your_money on July 15, 2006, 01:57:03 pm

Title: Car won't start
Post by: burn_your_money on July 15, 2006, 01:57:03 pm
I can't get my 84 rabbit to start anymore. The problem is that when the car is cranking the stop solenoid is not getting any power. When the key is in the run position the stop solenoid gets 12v. Any idea what's wrong? The glow plug relay worked fine in the 92 jetta I took it out of.
Title: Car won't start
Post by: burn_your_money on July 15, 2006, 08:05:44 pm
It's from a 92 TD, so it should have slow glows just like the rabbit should.
Also, the glow plugs come on even when the engine is warm enough to be started without them. Could that be a bad sensor?
Title: Car won't start
Post by: jtanguay on July 15, 2006, 08:27:38 pm
Quote from: burn_your_money
It's from a 92 TD, so it should have slow glows just like the rabbit should.
Also, the glow plugs come on even when the engine is warm enough to be started without them. Could that be a bad sensor?


im sure all '92 TD's come with fast glowing systems.  You may need to swap a fast glow relay system.
Title: Car won't start
Post by: burn_your_money on July 16, 2006, 07:02:24 am
Quote from: jtanguay

im sure all '92 TD's come with fast glowing systems.  You may need to swap a fast glow relay system.


Hmm I was always under the impression that all TDs had slow glows to avoid smoke at startup or something like that.
What about one from a 86 NA? would that be fast or slow?
Title: Car won't start
Post by: Doug on July 16, 2006, 09:46:14 am
I had an 84 Rabbit nonturbo that I believe had fast glows in it. I would try placing a positive jumper from the battery to the solenoid and then start. Or you could back off the injector unions and look for fuel leakage. I have seen the solenoid seize in the closed position. Just repaired one recently. Try this before swapping relays. You may be chasing more problems if you start that. Chances are if the relay worked yesterday it is good today with the exception of the glow portion which can open circuit because of the large amount of current that it handles.
Title: Car won't start
Post by: burn_your_money on July 16, 2006, 11:42:56 am
The stop solenoid is good. I have it rigged up to constant power and a kill switch. I can drive the car just fine. I did crack open the injector unions to bleed the lines, which made no differance in anything. I'm thinking it is something wrong with the "15 series" wire that the glow plug relay is hooked up to. It seems like it's be ran through the x-relay which is why I'm not getting power during cranking.
The car is working great with this relay, the light goes off and the car starts beautifully, so whether it's fast or slow, I think it's the right relay.
Title: Car won't start
Post by: Doug on July 17, 2006, 04:17:37 am
So it sounds like you have beat the relay problem for the solenoid but now the glow cycle is not functioning. I have seen these engines be impossible to start without the glows. I think that then they are borderline as far as the compression goes. A diesel in warm weather that is in good shape generally will fire after sufficient compression cycles. I put a cheap ammeter in series with the glow bus. That way I can monitor any changes in the glow plug conditions ie. shorted/ open circuited, reduced capacity.

Aside from that, the windshields couldn't seem to keep the water out of the car and usally it is dripping down through the relay panel where trouble gets started.
Title: Car won't start
Post by: jtanguay on July 17, 2006, 10:32:50 pm
the slow glow plugs can take around 20 seconds, correct me if i'm wrong?
Title: Car won't start
Post by: Doug on July 18, 2006, 10:17:48 am
Jt:

      I took a look at the at the Bentley. There is a fast system on the NT and a slow sytem on the TD. Neither relays nor glows are interchangeable. Fast system is about 20 seconds but the slow is upwards of a minute. There is a procedure to check relay operation which involves jumpering out the relay. It is lengthy so I am not going into it here. Get a book or send me an email.
Title: Car won't start
Post by: jtanguay on July 19, 2006, 06:45:26 am
hmmm... my 86 jetta took about 5 seconds in summer + about 20 in winter.  Same with my 92... both 1.6TD's (one mech, new one is hyd)
Title: Car won't start
Post by: Doug on July 19, 2006, 09:55:54 am
Right! They are both fast systems. I am talking pre "85.
Title: Car won't start
Post by: regcheeseman on July 20, 2006, 01:44:09 am
Am I missing the point, or is everyone else?

Quote
The problem is that when the car is cranking the stop solenoid is not getting any power.


Surely this is the problem and it's nothing to do with the glows?

My T4 did this and would only start when the ignition key was returned from the 'crank' to the 'run' position.

It was a dodgy ignition switch and cost £15 for a new switch assembly

As a check, run a permanent live to the stop solenoid and if that dont cure it, jumper across to the glows, count to 7 slowly and then crank it
Title: Car won't start
Post by: Doug on July 20, 2006, 04:42:05 am
I think you answered your own question. We covered that earlier.
Title: Car won't start
Post by: burn_your_money on July 21, 2006, 01:30:36 pm
I haven't had a chance to work on the car lately due to a huge storm and some stitches in my foot but for some reason when my engine is really cold it won't use the glow plugs. I have to crank it for about 5-10 seconds and then it starts. That's at about +15C. But then in the afternoon after it's been sitting in the sun in +25C weather the glows go on for about 5 seconds. Any idea what this is?
I've got the relay/ stop solenoid figured out enough to deal with it for now.
Thanks for all the help everyone  :D
Title: Car won't start
Post by: Doug on July 21, 2006, 02:48:00 pm
Try cleaning all the external contacts on the glow relay system icluding the head temperature sensor. The glow relay may need to be replaced. You could always pry off the cover of the relay, check and clean the internal contacts. Chances are they are burned to a crisp and only making contact under certain conditions one of which might be temperature related. Just a thought. Last time I priced one of those it was about $40.00.
Title: Car won't start
Post by: burn_your_money on July 21, 2006, 03:32:40 pm
Thanks Doug, That's what I was planning on doing this weekend.