it glows, then it doesnt glow, then it glows... what the heck!!!!
 

so half the time i try to start my car the filiment in the salt shaker glows, then half the time it doesnt. i went out just today, i let it glow for a while, and then tried to start it; its started and then just turned off a second later. so i tried to glow it again, but it failed to glow. the odd thing is i still tried to start it and it started right up. with the inconsistancy of glowing though, i dont dare to drive it anywhere too far where it might sit for a while in the cold. i dont know what to do. i am having my dad go and get a filiment from another 240D that we know works. could that be the sole problem?

rachelle

I'm assuming the "filament in the salt shaker" means the glow plug. New glow plugs are certainly essential for start-up, however it sounds like your relay may be faulty - or at least the wiring.

well, we just did a glow plug change not too long ago. we put the new pencil style glow plugs in. so that should be ok, we did have some difficulties wiring things up at first, but they are all good now. thats why its so confusing. :silly: how can i check the relay?

The relay on your '75 should be under the steering column - probably silver in color. If the plugs are inconsistent in glowing, or the glow light doesn't always come on, you might as well just buy a new relay. A lot of people like to putz around and test each individual component, or each individual wire, but believe me the $100 you spend on the relay for this car will be well worth it.

should i wait and see what happens with the new filament? i dont know for sure if i want to just jump in on another $100 purchase. i dont have that money right now

I understand about the money thing. I would see how things go once you install the new plug. I had a faulty relay in my '77 300D one time that showed the same symptoms. The plugs would glow sometimes, and sometimes they didn't. If the glow light didn't go on when I first tried to glow the plugs, I just kept trying until the light went on. You could also try a junkyard where you may get lucky and find one for cheap.

If you ever get desperate or get stuck somewhere becasue the relay failed, it's always a good idea to keep a piece of 8ga wire in the car. You'll be able to glow the plugs by placing one end on Plug #4 and the other on the positve battery terminal. It's a pain, but could get you through until a new relay can be purchased.

the wire deal is great to know. here is what i have observed so far. it will glow the firrt time, but if i try to glow it right after i will be out of luck.

I had a similar problem with my turn signals. i was pretty sure I had it fixed. I had a friend watch from the back as I activated the signal lever. "OK, it works, now it doesn't! now it works, now it doesn't! now it works, now it doesn't! now it works, now it doesn't!":rolleyes: :D

Does this mean the car won't start after glowing the first time? If that's the case it could be a bad plug. But you're saying that when you try to glow again that the plugs don't glow. That would be a relay issue of not turning the plugs on. Like I said, if the plugs don't glow the second time, keep trying until they do. For example if they start glowing after four tries, then it's definately the relay.

yeah one time i was following my bf who happened to be driving my car, and i saw the tail light wasnt working at all, then after about 10 minutes it slowly came on and got brighter and brighter, but very very slowly until it worked regularly.

i am going to drive it tomorrow to school... we will have to see if it starts after... could be very intersted :P

Rachelle,
I seem to remember you saying you had changed the glow plugs to the pencil type. If I am correct, did you add a relay or install a "fast glow" kit?
I don't think your car had a relay originally and the filiment (in the salt shaker)only glowed after the loop type glow plugs got current in a series system.
I believe you had to change the entire wiring to use pencil type glow plugs and should have changed the filiment.
If you used the fast glow kit they should have sent you a relay for the wiring and a light bulb to replace the filiment with.
If you installed a relay and made up your own pencil type system then you should have designed a different way to power the filliment.
I may be confused but I think you have something wired incorrectly.

well, we didnt install the fast glowing kit. i ordered it, but we didnt install it. we figured we would just do it later when we had time. so currently, we just have the new gp's wired up. we think they are wired correctly now, but you are correct in saying at one point they werent. and i dont think we got a bulb or anything with the new kit. i will check on that and let you know if that is any different

oh my god!!! i found the little light. we didnt know what it was because it had an orange cover over it... we asked i think, but no one gave us a response... i am going to run out to my car right now and install it. should that really make a difference? thanks you SOOO much:D

well, no success... it didnt light up. i am kinda frusterated with it.