190E intermittent starting problem

[E2.3]

Hello,
My 91 190E starts on the first twist of the key. Lately, sometimes it will crank normally, but will not start. After a couple of attempts it will start normally. I ruled out the neutral safety switch. I hear the fuel pump "priming" as normal. Any ideas? Thanks.

[Mike Murrell]

Does this problem occur:

a. Always
b. Only when motor is cold
c. Only when motor is warmed up

[E2.3]

It happens sometimes, it could be two days between no starts or two hours. It happens when cold or hot.

[sbourg]

Could be fuel pump problems - sticky check valve or such - but symptoms seem to indicate ignition. Look for spark, smell of raw fuel.

Steve

[Stephan Taylor]

I have the same prob with my 1986 8V. It happens cold and hot, it is not spark because when I spay start fluid it starts. Sometimes it keeps running after start fluid, sometimes it quits when it runs out of start fluid!!!! Resistance at temp sensor was 2880 at 25 degrees Celcius but I havent checked at other temps. I checked what I believe to be the overvoltage protection relay and there are 2 ea units under the cover just forward of the fuse box. One of them has two fuses directly pinned to the base and the other is a relay without fuses. I searched the part # on the relay and the replacement has the fuses on top of the relay!!! I just bought this car and don't know much about it but I have seemed to rule out ignition problems with the starting fluid, If anyone can help us I would really appreciate it!!!!
Steve

[GVB]

Sounds like you need to go find a reputable shop that specializes, or at least has experience with a Mercedes CIS-E system. It sounds like to me you have a eventually accumulator. Don't be concerned about spark if it does eventually start up, those EZL systems are great, bulletproof. You need to have a shop, or if you have some equipment, hook gauges up to the fuel distributor. After shutdown, hot, should stay above 2.5 BAR's. After about 15 min or so may drop down to as far as 1.2-1.6 BAR's. if it goes any lower you have a bad fuel accumulator. They absorb the shock of the fuel pumps on start up, and they eventually leak though and a line goes back to the fuel tank. Hopes this helps.
GVB

[Stephan Taylor]

Could you tell me how to acces the accumulator and the fuel pump and filter?
I really appreciate your response, Steve

[mctwin2kman]

The accumulator and pump and filter are above a panel under the car under the drivers side rear seat. Two little plastic nuts, 10mm I believe, hold the little panel under the car. Once you drop the cover you will see thepump suspended above it attached to the car.

[Stephan Taylor]

Thank you for the assistance, I was able to find them. I really appreciate the help!!! Steve

[Stephan Taylor]

Thanks for the help guys, I checked to see that I had power to the cold start injector and I did, so I took it to a friends shop and he will check the valve itself and the accumulator!!!! I have had it up there 3 times and he could not get it to fail!!! He scoped the fuel pump and it is good!!!