95 C280 wont start

[ScottyP]

Install a new EGR and EGR pipe to the newer one on my 95 C280. Once completed, I notice the idle was not as usual. During the process of removing/installing the EGR pipe, I had to pull the injector rail and loosen the Intake Mani. When reinstalling the injector rail, I noticed that the seals looked dry but just put some oil on them. Drove the car for a week without improvements.

Thinking the seals was causing my unsteady idle, I ordered a set of upper and lower injector seals. Replaced all the injector seals, let the system prime and attempted to start the car. Car would not start! Got out and looked under the hood to find gas everywhere. The upper seal on Cyl 4 was spilling gas everywhere and all over the garage floor. Cleaned up everything and changed the seal with an extra one purchased.

Now, the car starts for 2 seconds and then stops. Will not start again for 3-5 mins, but only runs for 2 secs. Pulled and tested the spark plugs; they are dry and have spark. Tested at the fuel pressure relief valve and it squirted across the room. Got spark, got fuel, got air = No Start!! What should I try next??

[Nelson Lago]

Check your EGR. If its open all the way it might be causing that problem.

[ScottyP]

Thanks Nelson for your reply..

I will attach the MightyVac and see if the EGR is opening & closing correctly.. Remember, I drove the car for a week between installing the EGR/EGR pipe and installing the new injector seals.

Im also pulling the injectors to check for good seals..

[ScottyP]

Update:

Checked the fuel relay & fuse = good.

Checked the OVP relay & fuse = good.

Checked EGR valve operation = good..

Lower Injector seals still looks new; engine hasnt reached operating temp since installed.

Still trying to find the source of the problem..

Anyone have other suggestions?? Please help..

[ScottyP]

Discovered that the fuel relay is clicking off when the car is started. Cant figure out why...

What would cause the fuel relay to turn off fuel?
Security system? short? what?

[ScottyP]

Installed new fuel pump relay.. No change

Any ideas anyone?

[Nelson Lago]

I think it's time to take it to the stealership

[ScottyP]

Waaay to broke for that!! Gotta fix myself or be without wheels for a few weeks... Tow, $150 analysis and whatever to fix it. Its at least $450 everytime I go in the stealership.. Min labor charge is $125.. Let not forget the shop supplies fee of $40.

Complete ripoff ! !

[V1Dreamer]

so you have fuel and spark for sure. but just because the engine is sucking in air, it doesnt mean that it knows how much air is being pulled in, and doesnt know how much fuel to inject to maintain the proper air fuel mixture.
from my understanding, your motor has the air intake pipe right where the secondary air/egr tube enters the intake manifold toward the rear of the motor close to the firewall.
check to see if the intake tube is still on its seat. removing the intake pipe that runs along the passenger side of your motor can easily pull it off of its clip. even that slight amout of un-metered air can cause your problems. oh and check if the mass air flow sensor is plugged in. if all of that is good. i would recomend getting a new mass air flow sensor. if your check engine light hasnt come on with a mass air flow sensor code. you should be able to go to your local auto parts store and get some maf cleaner. try that out before getting a new one. the price of those things have gone up quite a bit in the last few months.

[ScottyP]

Finally figured out what happened..

When the injector seal didnt hold and gas was sprewing out, the smart Mercedes system shutdown the ignition system by blowing the OVP relay which stopped the signal to the fuel relay... ... (note: the OVP fuse was still good)
Guess it kept me from Blowing Myself UP!!!

Once the OVP was replaced, the car started & runs without a problem.. :banana: This was a very painfull experience ! !

But now, Im on the road again! :D

A BIG Thanks to everyone here who assisted me thru this!!