progressively harder crank in 300E

[ShyJuan31]

hey all, I have an '87 300E and the crank is harder and harder to start. IF it starts the idle is super rough ang if i try to gas it it will stall but after about 10 minutes i put it in gear and srive it fine except the bad idle when i stop and the hesitation in accelleration.. but even that settles after 20 minutes of driving. plugs,wires,caps changed.... what could it be?

 

[paulcallender]

Does your ABS work too? (If it works, then it will light the ABS light before starting, but then go out once started).

If ABS isn't working, then this is almost certainly due to blowing the fuse in the Over Voltage Protection relay. Its located behind the battery, behind a little black plastic removable panel. 10A spade fuse, I think. When this blows, it reverts the fuel injection into a mechanical only mode, ie it doesn't include the (electrical) cold start functions.

 

[Jay a. nielsen]

hey all, I have an '87 300E and the crank is harder and harder to start. IF it starts the idle is super rough ang if i try to gas it it will stall but after about 10 minutes i put it in gear and srive it fine except the bad idle when i stop and the hesitation in accelleration.. but even that settles after 20 minutes of driving. plugs,wires,caps changed.... what could it be?

Wow, I habe the same year Benz, same model, and currently the same problem.
This is what I found out there tonight-

Question: 1988 Mercedes 560 SEL 5.6 mileage: 106. I really, really hope you can answer this one. Let me know if you need more details or if it is something that doesn't have a clear answer. My 560 sel periodically increases its idle while at the same time; the antilock brake light comes on. This behavior occurs at 10 or 15-minute intervals at times, or many times the car just idles fast with the ABS light on. Idle is as fast as 20,000 rpms. It has a new alternator and a new battery. I did notice there was no blow-by smoke seen when looking inside the breather with the motor running.

Answer: Check the ground wires, especially the ones around the computer area. Also, check for damage to the wiring looms.

- - - - -

Question: 1986 Mercedes 300 E mileage: 124000. My car ran fine until the Antilock light went on then the car started losing volts. Any idea where to start looking?

Answer: Check alternator output and also check for a bad diode in the alternator.



Please, keep me posted on your findings and I'll see what else I can uncover.

-Jay a. nielsen

 

[Jay a. nielsen]

ANTILOCK ABS light Rough Start

So, I drove my 300E across the state to my brothers house last night giving it a full battery charge, minus the headlight draw during the commute. This morning I "jumped it" with his Ford Explorer topping off the battery; just to be sure during the jump, I let the Benz charge for a few minutes before cranking over. It fired rite up! 8)
Usually my commutes are within the city. A stop here and a stop there isn't giving the battery the chance to charge as it takes a large draw to turn over the large 6.
At this point I believe it's an electrical issue. :idea: My guess is if the battery isn't completly up to par, it interrupt's the ABS, maybe even the fuel injection system?? making it start funky. I'll try a new battery and let you know.
Jay a.

 

[Jay a. nielsen]

Charging system

-No-go on the Battery, though it started better for a few days. I'm purchasing a new alternator this week.
-Jay a.

 

[landover]

Does your ABS work too? (If it works, then it will light the ABS light before starting, but then go out once started).

If ABS isn't working, then this is almost certainly due to blowing the fuse in the Over Voltage Protection relay. Its located behind the battery, behind a little black plastic removable panel. 10A spade fuse, I think. When this blows, it reverts the fuel injection into a mechanical only mode, ie it doesn't include the (electrical) cold start functions.

That sounds like the problem.I had one the other day with same problem The abs light was on and it run rough when started fuse was blown at relay behind battery .replaced fuse light went out and run ok .

Dont have to read all this mate just check the fuse

 

[Jay a. nielsen]

A fork in the road.....

Not a fuse problem. It's funny, I got a jumpstart from a buddy and it started perfect for 2 day after that, I somehow thought it fixed itself after that. Meanwhile, I didn't place the winning bid on an alternator on Ebay. About the time the auction was over it funked out again.... It's going in
9-25-04