w201 wont start after sitting for year and half
 

My brother and I bought a non running 1992 190e last weekend. I was able to get it to get it to start, but shut it off to fix a loose belt. Well it wont start now. I drained the tank and fuel system and replaced the gas, New cap, rotor, spark plug wires and spark plugs. i have a spark tester and am getting great spark compared to how it was when it first started. I am getting fuel to the mechanical fuel distributor( cracked the lines while my brother by passed the fuel relay). I noticed that only one of the fuel pumps is making any noise and vibrating. Do these cars need both pumps to run? Also, it will back fire through the intake and exhaust after I crank on it for about 15 seconds. It gets super close to starting, but wont quite go all the way.

I'm really good with the old diesel benz's and the JDM motors, but this guy has alot going on under the hood. Any ideas would be a great help.

Thank you

What happens when you do not bypass fuel relay?

Did you replace fuel filter?

Vacuum leaks and lean fuel condition can also cause backfire.

Check ignition timing.

ej has it. Ignition components have been changed, and now there is spark at the wrong time. Time to call NASA; it's rocket science!

I didn't know the W201 had points & condensor

And that condition has not been rectified.

No points and condenser, but they do have cap and rotor. With new wires, it's possible that the firing order got mixed up, hence the calls to check timing and firing order.

Firing order possible

benzdude42, I am sure you realize that a Bosch distributor cap has the corresponding cylinder number on each terminal, so it shows the firing order. Cylinder No. 1 is in the front.

Does it start off of starting fluid. That narrows it down real easy. Yes, you do need both fuel pumps to run!

I don't believen you adjust the ignition timing on these motors after a quick Google search. I've checked the firing order a few times (1342) with no luck. I'll have to check it out for vacuume leaks next.

Did you check the vacuum hose under the intake going from the intake boot to the bottom of the Idle Control Valve? Make sure all of the ICV vacuum hoses, top and bottom, are in good shape and tightly connected.
I've owned my '93 since new, and the only time it failed to start was when the bottom ICV vacuum hose split at the connector. Replacing these hoses are routine maintenance.

Congrats on the new purchase! In case there are other systems that you're going to be restoring, take a look at the link below to our DIY articles. They should help you with maintenance and any other issues you may run into! Post a photo of the new ride man.

Mercedes-Benz 190 W201 (1984-1993) Technical Articles - Pelican Parts

In my experience a problem like this is usually fuel related. Do you have a pop tester from your diesel experiences? If so remove the injectors and see if you can get them to operate a bit better (!)

Modern fuel (over here anyway) has a fair amount of bio content in it these days which means the fuel separates after a while - the water content causes havoc with fuel components.

I wouldn't be surprised if you find you need to replace the injectors and all of the rubber parts.

Make sure that the start valve operates.

#######

Whilst you are fiddling with these KE II CIS systems make absolutely sure that the rubber hoses running from the underside of the mixture unit and the air idle control valve and the breathing parts from the crankcase are well seated and leak free. It is quite easy to know something loose and then spend the rest of your life wondering why it seemed like it was going to start and now won't...

...keep your battery well charged.

Sorry about the late reply. I've also decided it was fuel related, I am getting 90 psi at the fuel regulator, but no fuel coming from the fuel distributor. I took it apart to clean it and broke the diaphragm. Had the rebuild kit over nighted, Should be here tonight. Can the idle control valve control fuel flow to the injectors? I know the top hose I broken right now.

Stretch, I thought the same thing. I dug my pressure tester out of storage last week. I soaked the injectors in powerful clear for a few days, but haven't tested them.

I got the fuel distributor working! Fuel doesn't over flow unless i presses on the fuel plate. The car still wont start though, its supper close. Its still backfiring out the intake manifold pretty bad. Do i need to adjust the fuel air mixer using that screw with the ball bearing in it?

Do you have all of the Idle Control Valve vacuum hoses tightly connected....top and bottom? Be sure to check under the intake boot to make sure it's pushed in tight.

Good news if the ball bearing is still in the mixture adjustment, means it hasn't been messed with.

I wouldn't play with that screw just yet.

The fuel shouldn't come up when there is no air flow going across the plate.

As soon as the engine is cranked air gets drawn across this plate (because the engine behaves like an air pump) and the setting should be about right.

I think you are going to be better off testing the cold start valve before fiddling with that screw. (After doing the vacuum hose checks as mentioned above)

Well I looked under the intake and Judy bumping the hose caused it t fall off. I put a hose clamp on it until I an get a new one. After playing around I was able to get the car to start for half a second and it dies. I decided to check the light codes to see if it had any. I got a code 4 (the air sensor under the fuel injection unit, and a code 9 ( EHA) could either of these cause the csr to not run or change the timing to cause a back fire? Ive search and found that these can cause idle issues, but nothing on not starting. I really don't want to buy a new EHA if I csn avoid it. I don't plan to keep the mechanical injection system once I know the tranny works and the engine is solid

The ICV vacuum hoses have to be on and tight (no leaks) all the way to the intake.
Sounds like you're making some progress.

I got it to run! i started to move the spark plug wires around after reading on form that someone had a really weird ignition timing compared to the 1-3-4-2 that the book says. I dont know if its my cap that is wrong or something else, but its running well at 1-2-3-4. I'm just glad that its running, now to the fun stuff! Thank you for your guys help!

Hey?

1 - 2 - 3 - 4

Mad...

...are you sure? If so there's got to be a reason for this - let me think about it...

Not knowing the history of the car, i cant really say what the last owners did. I'm wondering if the cap is numbered wrong, everything i saw on line told me the firing order of the motor, but didnt compare it to distributor cap. Attachment 142208 I took this picture from a different thread, but thats how my cap is numbered also.

See posts #3 & #4.

Re: "1-2-3-4"
The words of Daniel Patrick Moynihan apply:
"We are all entitled to our own opinions; we are not entitled to our own facts".

If you look at the cap in your picture and think of the direction in which the rotor in the distributor rotates I can see 1 - 3 - 4 - 2