Aboshi

Hi everyone,
Just cross posting into this thread because @ignorant had asked me to post here as well.
https://mbworld.org/forums/gl-class-...ml#post7595309
Hopefully one of us here can figure this issue out and get it nipped in the *** without pouring tons of money and time into things that don't work.
Just a refresh form my post:
Just got the truck the other day, took care of an oil leak that turned out to jut be a missing o-ring on the oil filler cap.
It leaked oil all over the exhaust manifold, alternator, and who knows where else down the side of the motor.
Cleaned it up as best as I could but this issue could very well be the cable linked in this thread.
Things I have tested so far:
Fuel pressure at the rail (52-60psi)
New BOSCH glass pack battery 1000 cranking amps
Ordered a new crankshaft position sensor (waiting for it to be delivered) but if this isn't needed I would rather not waste the time replacing it.
But if everyone suspects its the cable going form the alternator to the starter I might want to try that next. Has anyone run a test on the cable to make sure its pulling the correct amperage?

bhuter24

Hello guys,
I am having this issue as well. Also sometimes the burning rubber smell comes as well. Are they both related?

How hard is it to replace the positive cable?

Thanks

bhuter24

BTW i have 2008 GL450 with 85K on it.

Aboshi

I haven't changed the cable out yet because it got cold here fast! I need to move my half pipe in my garage to make room to work on the GL
I am definitely going to have to do this within the next week or so because trying to start the car today after a short trip it turned over very slow, paused and cranked again a few more times before giving up completely. I had to switch the car off and try again, and it started instantly. So I really hope it's just the positive lead cable. If there was more room at the starter I'd just hook up a meter and check the amperage

fkong777

My GL didnt start until I crank it 4 times or more. So I took my GL450 in to an indy, They took a lot of time to seek out the problem. He found that secondary air injection relay was broken and it was continually running when the car is on. it cause the wires under the relay block to overheat. So some of the wires are burned. Signals are not going thru to right places to start the car quickly. Tech say replacing the wire harness would be super expensive so he is replacing the burned wires under the block. it is going to cost $500 for labor and $40 for broken relays. Didn't get the car back yet. lets hope for the best.

fkong777

Update!!!!!: Changing relay and fixing burned wires didnt solve the problem.
Im still having starting issue intermittently.

Working on a couple things will update if it solve the problem

N_Jay

Does it always start on the 4th try.
Does it sometimes take less tries?
Any consistent theme? ( How long it sat, temperature, etc.?)
Does it crank at a normal speed?
Do you have a OBD tester with a start test feature?

Aboshi

@fkong777
Did you change out the positive lead cable to the starter?
Hopefully you narrow it down, I still haven't had time to change out the positive lead cable to test that theory yet

@N_Jay
For me its random, sometimes it will start the first crank, sometimes it will crank for at least 10 seconds, maybe a little less maybe a little more. So its totally random.
I highly doubt its the starter or by now it would have died by now. I also doubt its a fuel pressure issue because the starter just stops craning for a second before cranking hard again.
I guess I personally wont know until I change out this lead cable already. I just haven't even had time too see how involved of a process its going to be. I really hope its easy enough to just get my hand by the starter positive side without having to remove the exhaust.

N_Jay

Does it "stop cranking for a second before cranking hard again" by itself, or do you mean the next time you hit the key?

Aboshi

It starts by itself.

N_Jay

ECU, Stater relay, or maybe a loose/back starter cable, but just spit balling.

Sounds like a very wired problem.

ignorant

I wish you'd have tried the harness first.
A) Its not super expensive, probably a few hundred bucks more expensive than what you've paid for the relays.
B) Probably would solve your problem.

Please keep us updated on how you proceed. (The positive cable is 90 bucks or around that)

fkong777

Answering some questions.

* When it doesn't start... it can take up to 15 crank tries before it starts.
* I haven't changed out the cable which runs from the Jumper terminal junction box to the alternator then to starter. It is one cable that jumps the 3 locations.

I was concern with running my battery dead. One strange thing I did notice was when I connect a battery charger to the jumper terminal it started. I'm working this angle right now. Possible Jumper terminal box issue. Will keep you all posted.

eric_in_sd

I lived with a sluggish starter for ~20k miles. Changing the starter is cheap once you get past the hurdles of how the exhaust cages it in. It was reluctant / slow to crank; recharging the battery made it better; it was worse when the motor was hot versus cold; it mimicked all kinds of other issues, like fuel pressure and so on. For whatever reason, that starter has a very gradual fail profile.

Aboshi

So did changing the starter work for you?

I had a 2011 C300 I bought brand new and the starter went out on me 4 months later! It wasn't a gradual thing. One day it would work perfect and the next it wouldn't, after 3 days of that the starter was fully dead and wouldn't even move. The issue with what were all having seems more insidious than a failing starter. Plus I don't like throwing $ at a problem, because if its not the starter that's a hell of lot of labor on a whim. I know I can change it myself but it's too cold in the north east now. Shops charge $129-179 an hour here and there's no way I'm parting with over $1000+ to change a starter especially when its not a guaranteed silver bullet.

eric_in_sd

lol I probably should have put that in. Yes, it worked like a charm. Basically instant starts now.

It caused me tremendous grief because it endlessly seemed like it was something else. Fuel starvation, weak battery, etc. Compounding the problem is that it leads to excessive battery draining. Even my indy mechanic didn't diagnose it. First they said nothing was wrong, then they seemed a little puzzled when I showed how it was sluggish. I guess I'm pretty sensitive, because I suddenly noticed it cranking slower one day, and it steadily degraded from there.

Looking at your symptoms again, it sure does seem like the starter is at fault. Sudden sluggishness followed by intermittent degradation.

Check out Mercedes Medic for tips on changing the starter without removing the exhaust.

Aboshi

Good to know a new starter worked for you
Guess I will have to get some heaters out in the driveway and do the remove the engine mount method ;(
I guess I wont have a choice but to try the starter first.
Thanks for the insight

ignorant

bhuter24

I would assume so. I had my vehicle on the lift and looked to replace the harness that is mentioned alternator to starter, I could not even see the harness that goes to the battery. to replace the starter it looked like you would have to remove the heat shield that runs next to the catalytic converter. I have not replaced either one yet and hoping would not have to do it either

ignorant

fkong777

Im at a lost...
so far I replaced battery, MAF sensor, sparkplugs. I replaced the Jumper junction box 2x100amp and 1x 40amp prefuses. My Indy replaced the Crank position sensor. Nothing helps. Its getting worse. But Now I get more of a consistency of after driving. I have to wait 5 hours before it will start. My indy didn,t think it is the starter because it cranks fine.

My Indy is thinking it is the engine ECU. which is a dealer part at about $2000.
I dont want to keep throwing in money to try - harness and starter.

This thing is falling apart after being 10 years old. Frustrated!!!!!

ignorant

I'm really sorry to be the first one to say this but:

You had to try the positive cable harness first.
This is not my opinion, it is the combined experience of this forum.
I will "try" that one first even though it costs 500-1000 dollars, that would still be my first bet.
I don't want to live with my disappointments after each "cheaper and worth-a-shot" fix effort.

The replacement part is 100 bucks, can you get a quote on labor for that part from your mechanic? Maybe it's not that expensive at the end.
You indy owes you a favor now, right?

eric_in_sd

Slow cranking when warm is a symptom of a failing starter. See my posts above. I don't get why people keep saying wiring, but - if you remove the engine mount, the starter is just not that hard to change.

My indy didn't recognize the weak starter either. It cranked at a reasonable speed, but I think the ECU avoids fuel delivery when the rotation isn't fast enough. Changed to a new starter and it jumps to life basically instantaneously.

N_Jay

What is "falling apart" or is that what you call one problem just because people can't figure it out?

fkong777

Actually 2 months ago. The A/C compressor & pulley just exploded. took out the belt and couple of other pulleys with it. That was a $1500 repair. So that's what I meant by failing apart.