This is weird. Won't start... Sometimes w123 1982
 

I have a 1982 300td. Here's the problem: I went to fire her up the other day after my lunch break the other day, and nothin!! Crap! Seems like the starter, right? So I dropped a new starter in right there in the mall parking lot. Tons of fun.

Worked just fine. Way stronger starts than before.

Now here's the part I need help with. Sometimes the starting is not reliable. Generally, the longer I let the glow plugs heat, the worse my odds are. So I'll have to turn the key back, then go straight to firing her up. That doesn't always work though. The only other quick fix it seems is to throw the car down into drive, then pack into park. That seems to do the trick, even though yesterday I did that trick 3-4 times before she even wanted to engage.

Just FYI, when the problem is happening, the starter isn't engaging; there's no cranking. Just a simple "click!" before my heart starts sinking.

I love this car! I need to know how to diagnose this starting problem. Seems electrical. My relays are fairly new, I think they're okay. I don't know what else it could be.

PS - This forum is the best thing to happen to us DIYers.

Could be a neutral safety switch, if you are having to move the transmission selector around, also check the condition of your battery.

trans switch
 

Hold the key in the start position ( with your right hand ) and take the shifter in and out of park real fast (with your left hand) if this changes anything it could be; the little plastic bushings under the car on the trans linkage ($2), or the neutral safty switch ($?). J:cool:

Wouldn't the "click" show that the Neutral safety switch is working? The click sound is usually the solenoid engaging, but the starter does not have enough power to turn the engine. Doesn’t the NSS interrupt power to the solenoid?

How is your battery? Have you had it load tested?

I think there's a bad connection somewhere carrying enough current for the glow plugs but not enough for the starter. Clean all battery, starter and ground connections before digging deeper.

it's totally the neutral safety switch. around $55. i've had this happen on 2 different cars...above suggestion is best, holding the key in the 'start' position, move the shifter around. i can almost guarantee it'll start turning.

you replaced the starter in the mall parking lot? :confused: ouch, man, that's a lot of work...

I agree.

Ditto on checking the grounds. Especially the engine-chassis ground strap.

Changing starter in the parking lot, been there done that! Do-able but not fun. (BTW, this is the exact same thing I did before finding that the bracket the eng.-chassis ground attached to was loose.;) )

The only reason I might say it wasn't the connections was because it usually WILL start after moving the shifter around. The battery is less about 6 months old, and again, the car does start, after a little.... sweet lovin'

Seems like the neutral switch seems right.

You shouldn't hear a 'click' if it's the neutral safety switch.

I shouldn't hear the starter solenoid click, but you may hear other relay clicks from under the dash. How about trying to jump the starter from the contacts under the hood? AFAIK, that will bypass the NSS.

Ive gone through all the rituals - Pushing the car then putting it in park(thinking the starter might be stuck), went through all the gear selection, contemplated on changing the starter, added new ground wires all over the body. What cured mine was an original bosch alternator. Keeps the battery fully charged all the time to crank that engine of ours.

I'm quite sure it's the neutral saftey switch. The "moving the gear selector" trick works every time. But... It's a pain in the butt. Does anyone have any experience changing the thing out? I could use some pointers. I got under the car and checked it out, and it looks like a pain.


Chris

its easy, remove the 10mm bolt and nut from the lnkage, pop that off, then remove the two bolts holding the nss on and it comes right off. some have a clip that may or not break but its cheap so be sure to get that too if yours has it.

Do you have a picture or diagram? I'm not sure if i'm looking at the right thing.