Author Topic: HELP!!! MISFIRE/STALL  (Read 979 times)

s class

  • W116 Addict
  • ****
  • Posts: 4,174
  • I'll keep the 116's, the rest can go
  • Location: Squeezing 3 W116's into a double garage
Re: HELP!!! MISFIRE/STALL
« Reply #15 on: 30 January 2021, 12:13 AM »
I suspect you may have throttle position switch calibration issues, that the idle contact switch is not working correctly
  PM me your email address and I'll send you the procedure to set it up.

Have you played with the idle air/fuel ratio setting potentiometer on the side of the engine ECU in the foot well?

'76 6.9 Euro, '78 6.9 AMG, '80 280SE, '74 350SE, '82 500SEL euro full hydro, '83 500SEL euro full hydro , '81 500SL

AceWolff

  • Enthusiast
  • *
  • Posts: 27
  • W116 Newbie, W123 Enthusiast
  • Location: Western New York
Re: HELP!!! MISFIRE/STALL
« Reply #16 on: 31 January 2021, 08:17 AM »
I didn't know I had to gap the points. I've never had to deal with them before.

How do you change points properly, because I just put them in with no extra steps.


No I have not, I'm fairly new to this car. And before this I've pretty much only run diesels

You can reach me at

Guywithphone@gmail.com
~Ace

AceWolff

  • Enthusiast
  • *
  • Posts: 27
  • W116 Newbie, W123 Enthusiast
  • Location: Western New York
Re: HELP!!! MISFIRE/STALL
« Reply #17 on: 01 February 2021, 05:20 AM »
Does this car have the OVP?

I have a hard time finding info on the SE in particular.

But I am also having some other electrical issues and I've read that this can cause both problems I'm having.
~Ace

celberg

  • Enthusiast
  • *
  • Posts: 19
  • W116 Enthusiast
  • Location: Lund, Sweden
Re: HELP!!! MISFIRE/STALL
« Reply #18 on: 02 February 2021, 09:49 AM »
First thing first. Your car went well for a 6 hours drive and suddenly not at all?

No ovp in d-jet.

Do you have the rotor with rpm-limiter? Even if it's new it can malfunction. I had to put another rotor in a year ago. This time i took the one without rpm-limiter.

You might have dirty triggerpoints for the injection valves. Lift the ignition distributor, take the triggerpoints out and clean them. Make sure you put the distributor back with the rotor at the same place.

If you haven't played with the throttle position switch, don't do it.

The idle air/fuel ratio setting potentiometer on the side of the engine ECU does not affect the fuel/air ration when you drive, it only affects on idle. Therefore You can leave that.

350SL 1973
350SE 1975
SL500 1996

Alec300SD

  • Classic
  • **
  • Posts: 177
  • W116 Enthusiast
  • Location: San Mateo, CA
Re: HELP!!! MISFIRE/STALL
« Reply #19 on: 02 February 2021, 10:00 AM »
Did you change the fuel filter after you ran out of gas?

1974 450SE California emissions

Long story short, bought car sight unseen, drove ⁶ hours home (drove like a dream)

Now the car will not stay running unless I'm on the gas, shakes misses and stalls.

Just finished putting on new points/wires/plugs/cap/rotor/cool


P.S. car ran out of fuel prior to this

New fuel line from tank to pump.

I can't figure it out, the throttle response is great but it won't stop misfireing.

79 W116 300SD 'Stormcloud' new as of 10/22/2017
78 W116 300SD 'Desert Rose' new as of 01/26/2014
83 W126 300SD 'Rena 2.0' with engine from 82 W126 300SD Rena' (SOLD and crushed 11-20-2017)

AceWolff

  • Enthusiast
  • *
  • Posts: 27
  • W116 Newbie, W123 Enthusiast
  • Location: Western New York
Re: HELP!!! MISFIRE/STALL
« Reply #20 on: 04 February 2021, 07:34 AM »
First thing first. Your car went well for a 6 hours drive and suddenly not at all?

No ovp in d-jet.

Do you have the rotor with rpm-limiter? Even if it's new it can malfunction. I had to put another rotor in a year ago. This time i took the one without rpm-limiter.

You might have dirty triggerpoints for the injection valves. Lift the ignition distributor, take the triggerpoints out and clean them. Make sure you put the distributor back with the rotor at the same place.

If you haven't played with the throttle position switch, don't do it.

The idle air/fuel ratio setting potentiometer on the side of the engine ECU does not affect the fuel/air ration when you drive, it only affects on idle. Therefore You can leave that.


I replaced the points on the top half, does this also have the horseshoe shaped trigger points?

I don't know how to tell if it has an rpm limiter.

I have not changed the fuel filter. For some reason it still hasn't arrived at my house yet.
~Ace

AceWolff

  • Enthusiast
  • *
  • Posts: 27
  • W116 Newbie, W123 Enthusiast
  • Location: Western New York
Re: HELP!!! MISFIRE/STALL
« Reply #21 on: 04 February 2021, 07:35 AM »
I will also note, someone cut all the wires for the condenser out
~Ace

celberg

  • Enthusiast
  • *
  • Posts: 19
  • W116 Enthusiast
  • Location: Lund, Sweden
Re: HELP!!! MISFIRE/STALL
« Reply #22 on: 04 February 2021, 10:47 AM »
First thing first. Your car went well for a 6 hours drive and suddenly not at all?

No ovp in d-jet.

Do you have the rotor with rpm-limiter? Even if it's new it can malfunction. I had to put another rotor in a year ago. This time i took the one without rpm-limiter.

You might have dirty triggerpoints for the injection valves. Lift the ignition distributor, take the triggerpoints out and clean them. Make sure you put the distributor back with the rotor at the same place.

If you haven't played with the throttle position switch, don't do it.

The idle air/fuel ratio setting potentiometer on the side of the engine ECU does not affect the fuel/air ration when you drive, it only affects on idle. Therefore You can leave that.


I replaced the points on the top half, does this also have the horseshoe shaped trigger points?

I don't know how to tell if it has an rpm limiter.

I have not changed the fuel filter. For some reason it still hasn't arrived at my house yet.

A0001582331 is the OEM nr for the one without limiter and A0001582931 the one with. Google with picture and compare with your own.

The trigger points are below the single point for the timing. You see a cable attached to it. You have to take the distributor of the motor.

I don't have the condenser in my 1975 350SE and I'm not alone. You don't have to have it.

You have to set the points and timing correct. Use Youtube if You don't know how to do it.
350SL 1973
350SE 1975
SL500 1996

AceWolff

  • Enthusiast
  • *
  • Posts: 27
  • W116 Newbie, W123 Enthusiast
  • Location: Western New York
Re: HELP!!! MISFIRE/STALL
« Reply #23 on: 05 February 2021, 12:39 PM »
Okay cool,  I'll look into this,  if it doesn't help then it's too the shop.

It's too cold outside to troubleshoot.

Thankfully I have an inn with the shop I'm going to.
~Ace

AceWolff

  • Enthusiast
  • *
  • Posts: 27
  • W116 Newbie, W123 Enthusiast
  • Location: Western New York
Re: HELP!!! MISFIRE/STALL
« Reply #24 on: 08 February 2021, 06:06 PM »
Well,  it's going to the shop.

It was 4 degrees earlier and I just can't deal with it.
~Ace

beytan

  • Newbie
  • Posts: 3
  • 280se W116 D-Jet owner
  • Location: Hampshire UK
Re: HELP!!! MISFIRE/STALL
« Reply #25 on: 18 February 2021, 07:09 AM »
I had a similar problem with my 280se D-jet and it was the control unit ECU ( the big box of electronics that controls everything) I struggled with so many ideas but I now have 2 spares as the replacement sorted the problem immediately. The ECU is a mass of resistors,capacitors attenuators etc. My problem was that the car started and ran for about 10-15mins before it start playing up and misfiring. I only discovered this after replacing the entire ignition system from coil to sparks, aux air valve, all vaccum hoses, sensors and the MAP pressure unit. I found a used ECU for £80 and it worked fine immediately. The problem with the D-JEt is that it is wonderful when its running right but there's a reason why Mercedes opted to go for the mechanical K-Jet after running the D-jet for just  a few years.  I have an 83 280ce coupe on J-jet and never had a problem in 11 years of weekly use. But the D-jet is quicker and doesn't suffer from flat spots  in power.  Hope this helps
Beytan

AceWolff

  • Enthusiast
  • *
  • Posts: 27
  • W116 Newbie, W123 Enthusiast
  • Location: Western New York
Re: HELP!!! MISFIRE/STALL
« Reply #26 on: 20 February 2021, 10:21 PM »
So it's been at the shop for like 3 weeks and all they tell me is it needs to be retimed. They quoted me $900

Fuck that,  it's home now,  I'm going to be putting a canopy over the front with a little heater and get to work.
~Ace

AceWolff

  • Enthusiast
  • *
  • Posts: 27
  • W116 Newbie, W123 Enthusiast
  • Location: Western New York
Re: HELP!!! MISFIRE/STALL
« Reply #27 on: 20 February 2021, 10:22 PM »
Probably tomorrow though. It's 1:30am right now here in Western NewYork
~Ace

Alec300SD

  • Classic
  • **
  • Posts: 177
  • W116 Enthusiast
  • Location: San Mateo, CA
Re: HELP!!! MISFIRE/STALL
« Reply #28 on: 20 February 2021, 11:03 PM »
I used to have a K-Jet 79 Volvo 245DL wagon years ago, and  the site linked below was an invaluable reference guide.
Hopefully, it will help you to troubleshoot your D-Jet system

https://jetronic.org/en/
79 W116 300SD 'Stormcloud' new as of 10/22/2017
78 W116 300SD 'Desert Rose' new as of 01/26/2014
83 W126 300SD 'Rena 2.0' with engine from 82 W126 300SD Rena' (SOLD and crushed 11-20-2017)

AceWolff

  • Enthusiast
  • *
  • Posts: 27
  • W116 Newbie, W123 Enthusiast
  • Location: Western New York
Re: HELP!!! MISFIRE/STALL
« Reply #29 on: 22 February 2021, 04:20 PM »
So, try this on for size.

I retime the points, I bumped the starter until it was on cyl 1 then gapped points at .014.


So I go to start the car, and hear a pop noise, come to find out, the fuel hose from tank to pump (which I just changed because it was leaking like a siv) explodes.

Excuse me?

So I guess I'll be ordering a fuel pump maybe? I don't even know.
~Ace