w124 problems Please help!

[the flower man]

hello all!i am new as a member hear but have read posts on hear for a long time and now i realy need help
i have a 1991 mercedes w124 230e saloon.i love my car but i cant fix this problem.she starts and then stops straight away(stalls) but this was out of the blue, stopping for a while after driving 30 miles.went to start her up.she fired as useral and then stalled.i had to get her recovered back to my mum and dads as it was closer.
so far i have changed.
fuel pressure regulator
ovp relay
fuel pump
fuel filter
fuel relay is opperating and i have 13v at the pin on the relay to the pump.the pump pulces when ignition is on and comes back on as she fires.
i have put a presher gage on the fuel meater head.she holds pressure at 2.8 bar for over 20 mins after attempt to start.turning the engine over shows 4.8 bar. the fuel pressure actuator is showing 17.8 oms accross the pins which is inside tollerance i beleve.im now worried that its an ecu fault.if anyone knows what i should do or test next and how please let me know.self employed and now very worried! btw, sorry for spelling mestakes,am quite dieslexic. thanks for reading.

 

[carat 3.6]

Welcome to the forum, are you getting a decent spark at the plugs?

 

[GP801]

Have had similar on a 300e-24. It was the distributor cap that had a small crack in it. might be worth checking it.

 

[boomtings]

Not sure if it helps you but on my 300-24 , I found that my fuel pump relay worked during cranking but would not run after, hence my car would start and then stall seconds later.

1. the relay is triggered for a second on ignition position 2. (pressurises the system?)
2. on engine crank.
3. on rpm signal between 400-cutoff rpm.

 

[the flower man]

thanks for the reply,dizzy and roter are 9 months old.i havent checked the spark as i had the initial fireing up but it is a good point,i may be loosing spark.
there is a wire to the coil from the ignition via the amp on the front wing.would this be anything to look at or is this on the same circuit as the cold start valve?

 

[the flower man]

thats interesting!i didnt know about the 3rd signal.is there any way of checking for this?

 

[the flower man]

forgot to say that when she fires up i can catch it with the throttle and keep her above 3500 rpm,she misses alot but will keep running.anything below that rpm she cuts out.do fuel presher actuators stick at all?would this be some where to start with?thanks for bearing with me.

 

[brigadier]

As you've already changed most of fuel delivery parts and the problem started out of blue, i would think that ignition is at fault.
maybe ignition module? Have you checked spark plugs?

 

[grober]

Sounds like the EZL ignition unit is on the way out. quite expensive to replace due to their rarity but you might be able to pick one up second hand- other possibility is that the HT coil insulation is breaking down.

 

[the flower man]

thanks grober and brigadier.i havent checked the spark.tbh i have no kit to do it with.i do need it so i will try and get one tomorrow.
funny you both mention the ignition module.about a year ago i had a strange fault,i would drive about 20 miles and she would start cutting out for no reason.if i left her for 10 mins or so,she started and ran like nothing had happened.it turned out that the copassitors in the ignition modual had over heated because the heat dispersant gell between the heatsink and the body had dried out.the ecu could no longer see the enginne pulce and would then shut the fuel pump down.i took it off and cleaned it then put computor heat sink jell back on and re mounted it.problem stopped as soon as i did this.22.000 miles last year and no probs till now.is there any way of telling by testing this itham?

 

[the flower man]

oh,do i need to look at the crankshalft position sencer or would these not do this type of problem?

 

[grober]

Your best bet is a small garage with an old oscilloscope type engine analyser and someone who knows how to use it- should pick up any ignition problems.

 

[brigadier]

also you could try and read if there are any fault codes present?

 

[the flower man]

ok,no one seems to know what they are doing in south london mate.i need to fine an enthusiast in my area.i have heard you can ground the ecu on one of the test point pins and it flashes the fault code through a 12v bulb attached to the earthed wire.is this true?

 

[carat 3.6]

ok,no one seems to know what they are doing in south london mate.i need to fine an enthusiast in my area.i have heard you can ground the ecu on one of the test point pins and it flashes the fault code through a 12v bulb attached to the earthed wire.is this true?

I think it has a return point built in to the test port. Have a look at this: Diagnostic code reader tool for Mercedes W 124 201 300E 190E E320 300TE 300CE | eBay

 

[grober]

this is a link to a download site for the 190 manual -- shares the same ignition electronics as your car. Modified Technologies, Inc | Enthusiast Gear


here's a comprehensive list of fault codes

http://www.mbslk.de/files/artikel/r170_fehlercodes.pdf


and here's the instructions about how to make a fault code reader [Home Brew DTC Tool] for yourself about 1/2 way down the page K6JRF Auto Page
__________________

 

[the flower man]

mr grober.that is amazing!its just what i needed!!i will download it as soon as im on a different computor as this one is right on the edge of self distruction(i know how it feels lol)i owe u one mate!

 

[gm255]

check you dont have a vacuum leak. I had a large leak one time on my 300CE and the car would run rough as a pig at low revs. If i could catch it, it would rev over 3500 fine!

Just another one to check.
Best regards
G

 

[nevilledoreen]

Hi flowerman I have similar problem with my 1993 ,300SL I have replaced all the parts you did .
How have you resolved this problem
Regards
Neville

 

[ray_hennig]

mr grober.that is amazing!its just what i needed!!i will download it as soon as im on a different computor as this one is right on the edge of self distruction(i know how it feels lol)i owe u one mate!

If you're stuck for help in S London, try Steve Redfearn in Wimbledon. He knows this vintage of vehicle and worked on my 450SLC, 300E, 500SL, 280TE etc. etc.

RayH