Author Topic: would the car die this way due to alternator? (Read 7459 times)

backwoodsvw · « **on:** March 15, 2009, 05:12:14 pm »

First a thanks for the forum, it has helped me troubleshoot no glow plugs contributing to a no-start condition already.. .however the car runs for a few minutes and dies.

car is a 95 golf, with what I believe to be a '89 1.6 n/a engine

I'll read more tonight to locate the proper markings to confirm..

If the alternator is not charging the battery.. would it run fine, until the battery drops below 12V, then cut out due to the fuel shut off solenoid not having enough voltage to stay open?

I intend to charge the battery overnight with my trickle charger, and have the g/f start it while I confirm inadequate voltage.

When I tested the battery after it died tonight, it was 11.98V..

Vincent Waldon · « **Reply #1 on:** March 15, 2009, 06:57:08 pm »

The fuel solenoid will run at quite a bit below 11v... I know one person who ran it on a 9V battery as a test... so I suspect something else is going on.

jtanguay · « **Reply #2 on:** March 15, 2009, 07:04:25 pm »

could be some corrosion. clean the contacts with WD-40 or something similar (wire brushing helps too)

to identify the 1.6 vs 1.9 simply look at the valve cover. the 1.9 has 3 mounts on the top that are clearly visible, and the 1.6 has them on the outer edge.

zyewdall · « **Reply #3 on:** March 15, 2009, 09:05:11 pm »

Yeah, the fuel solenoid should engage with quite a bit less than 12 volts. I think I read around 6 to 7, but I can't find that post any more -- it was a long time ago I saw it. The voltage that goes to the solenoid when it's cranking is a bit lower than 12 volts due to the heavy draw from the starter motor. Have you testing the voltage while its running? It should be 13.5 to 14.5 volts. One odd thing with the VW alternators is that they need to be revved to start charging -- if you start the engine and let it idle, sometimes they won't charge. But if you rev it up to 2500, then it will start, and keep charging even at idle. I'm not sure if that's stock, or just ones with kludged wiring harnesses (both the diesel VW's that had that behaviour, we made our own harness feeding the alternator exciter signal from a line tapped into the fuel solenoid feed, with a resistor in line to prevent it from backfeeding the solenoid enough to keep it from being able to be turned off).

backwoodsvw · « **Reply #4 on:** March 16, 2009, 08:45:26 am »

TY very much ... you are all correct.

Car started no problem again this morning..

volts across the battery were into the 13's.. so alternator is OK

I do have quite a few bubbles flowing from the fuel filter to the IP.

It makes sense to me now... she is pulling air to the point of stalling.. then is tough to start till it blows free....running the battery down.

I'll read up for my next steps.. I'm so close I can taste it, she starts and runs fine.. if I can nip this problem we might actually get this car on the road.

thanks again

jtanguay · « **Reply #5 on:** March 16, 2009, 09:53:32 am »

have you changed the fuel filter? its a very good idea. i eliminated my fuel pre-heater because it was leaking air into the system...

zyewdall · « **Reply #6 on:** March 16, 2009, 11:19:57 am »

You might try putting a separate lift pump back by the fuel tank. I've done that (just a $12 fuel pump designed for a carbureated gas gar) and it self primes the fuel system up to the IP pretty nicely, after changing hoses or filters or such. Seems like it should be less chance of having bubbles in the system that way too.

Smokey Eddy · « **Reply #7 on:** March 16, 2009, 12:07:01 pm »

new hoses or even just good strong hose clamps fixed my air leaks.
And a new shaft seal on the IP. But that's quite a bit bigger of a job than just changing the lines to the pump.

I've never needed a pre IP fuel pump (lift pump). Mine primes with the injector lines cracked (or off) from sitting for months in about 15 seconds.

I also STRONGLY recommend a new fuel filter. I change mine every 6-7,000km or so. (give or take a couple thousand of course)

jtanguay · « **Reply #8 on:** March 16, 2009, 12:13:44 pm »

lift pumps do extend the life of a filter... and aren't a bad idea. i would only use a solid state 4-7 psi one though.

backwoodsvw · « **Reply #9 on:** March 16, 2009, 12:20:29 pm »

fired up the 98 chev 2500 6.5L TD to head into town for the new fuel filter this afternoon, at least I"ll know its new, and can work from there.

I simply bolted it up.. w/o priming it, somewhat against my better judgment, but it ran on the fuel in the lines.. started to sputter died a few times, and now my battery is below 12V again. It was pulling bubbles, but I"d expect it to...

off to read the best way to get em out.. while I wait for it to charge.

I knew I shoulda syphoned a bit out of the truck to prime the filter at least.. duh... live and learn.

jtanguay · « **Reply #10 on:** March 16, 2009, 12:59:57 pm »

forgot to add that lift pumps reduce the chance of pump cavitation :wink:

backwoodsvw · « **Reply #11 on:** March 16, 2009, 04:34:25 pm »

She Lives!

only to reveal the next problem in the chain.. but she is running.

Boosted her with the truck until the air ran through and she coughed to life... only to die in the same fashion as before...however no more bubbles.

I had done a couple of rad hoses, and knocked off the fuel shut off solenoid wire, however when time came to hook it up, I had two choices. I obviously picked wrong... that wire must have been associated with glow plug system? or something else that shut off the 12V after running temps start coming up.

I think this, as now, my glow plug light isn't coming on, however she is warm enough to start.. and actually run up to temp.

Tried to move it a bit. .parking brake is stuck.. no biggie, and maybe much bigger problem.. I have fuel leaking from a fitting on the IP..

I'll post pics in the AM, with daylight...

I'm just enjoying the fact that she runs.. despite my ham handed mechanic abilities.

TY all.

backwoodsvw · « **Reply #12 on:** March 17, 2009, 09:58:14 pm »

freed the parking brake, by moving it back and forth..

she started fine this AM with just below 0C, block heater not plugged in, so encouraging to say the least.

seems to run hot to me, I'm so damn nervous of overheating from what I've read here...

not that the gauge goes over, or she boils the can over... just seems hot when I get back from very short scoots up and down the road..

crossing my fingers just an airlock in the hoses. I've read here to idle to temp, with the can cap off.. rev a bit should clear it I hope. squeezing hot hoses is no fun.

just a note.. jtanguay.. I am a 'shwa boy, was there today in fact to grab the kids over march break... small world and TY, your posts in other threads have helped me already.. a couple times over.

Rabbit TD · « **Reply #13 on:** March 17, 2009, 11:21:17 pm »

Quote from: "zyewdall"

Yeah, the fuel solenoid should engage with quite a bit less than 12 volts. I think I read around 6 to 7, but I can't find that post any more -- it was a long time ago I saw it. The voltage that goes to the solenoid when it's cranking is a bit lower than 12 volts due to the heavy draw from the starter motor. Have you testing the voltage while its running? It should be 13.5 to 14.5 volts. One odd thing with the VW alternators is that they need to be revved to start charging -- if you start the engine and let it idle, sometimes they won't charge. But if you rev it up to 2500, then it will start, and keep charging even at idle. I'm not sure if that's stock, or just ones with kludged wiring harnesses (both the diesel VW's that had that behaviour, we made our own harness feeding the alternator exciter signal from a line tapped into the fuel solenoid feed, with a resistor in line to prevent it from backfeeding the solenoid enough to keep it from being able to be turned off).

Everyone of my Rabbits, 3 of them over the years all did this even with new alternators, just tap the throttle and the light goes out . I guess it's just the design of the regulator and they areknown for failing too.

jtanguay · « **Reply #14 on:** March 17, 2009, 11:23:59 pm »

Quote from: "backwoodsvw"

freed the parking brake, by moving it back and forth..

she started fine this AM with just below 0C, block heater not plugged in, so encouraging to say the least.

seems to run hot to me, I'm so damn nervous of overheating from what I've read here...

not that the gauge goes over, or she boils the can over... just seems hot when I get back from very short scoots up and down the road..

crossing my fingers just an airlock in the hoses. I've read here to idle to temp, with the can cap off.. rev a bit should clear it I hope. squeezing hot hoses is no fun.

just a note.. jtanguay.. I am a 'shwa boy, was there today in fact to grab the kids over march break... small world and TY, your posts in other threads have helped me already.. a couple times over.

glad to hear! do you live far from the 'shwa? i could show you my mTDI when i fix the heater core and install the new transmission & clutch. the old mk2 trans just doesn't do the low torque justice! :twisted:

btw have you verified that the rad fan kicks on? i got really screwed when my rad fan quit on me. i was on the highway when we got to an accident (highway closed to one lane...yay :roll:), so i was idling and then steam coming from the hood :roll:

not the best time to find out that it quit... in this weather we currently have, the ambient temps should be enough to cool the engine while the car is moving, but not when stationary. just something to take into consideration. oh btw, my fan would work sometimes, and then not others... it was pretty pathetic, so keep an eye on it if you have A/C as those tend to fail... a lot