96 Mercedes c280: advice to start?
#1
96 Mercedes c280: advice to start?
MIL's c280 has sat idle for maybe 6 weeks, and now it won't start. The battery turns over but the engine won't catch.
Being out of my element at best (because an engine is involved) and having no better ideas I sprayed engine starter fluid into an air intake. The engine *almost* catches but still will not start.
Any ideas or DIY things I can try?
Thanks~
Being out of my element at best (because an engine is involved) and having no better ideas I sprayed engine starter fluid into an air intake. The engine *almost* catches but still will not start.
Any ideas or DIY things I can try?
Thanks~
#2
Basics; spark and fuel. Pull a plug wire and lay near a ground source; check for strong consistent spark while cranking. Since it "almost" tries to start with starting fluid, I'm inclined to think it's a fuel delivery problem. Could be anything from a blown fuse/dead pump relay to a clogged filter to a dead fuel pump. When you turn the key on, have someone listen at the fuel filler to see if the pump can be heard to run for a few seconds before cranking. This will show that you at least have power to the pump. Next step would be to check fuel pressure; this will require a pressure gauge if you can beg/borrow/steal/rent one.

#3
TG is right.
here's a wild thought.
1. car set for longer time - no fuel in fuel lines.
2. attempting to start now - allow some time for fuel pump to build up fuel pressure.
3. if that was not done - as a result, you try starting flooded engine now, as it did not catch right away, then plugs got sprayed with unburnt fuel, wet, and flooded
4. as a result, you either start engine in "flooded" manner, or remove spark plugs, crank engine with starter few turns, and let fuel evaporate through plug holes. In between, take propane torch and burn plugs clean. reinstall, let pump prime the engine, and try restarting.
Even several plugs cleaned that way may start the engine, and then the rest picks up.
"Flooded" engine starting is: have fully charged battery; press alll the way down on the gas pedal and HOLD, while cranking engine with starter; HOLD; it should, normally, crank, crank, then start sputtering - HOLD- then start catching; the very moment it starts catching, you should start SLOWLY releasing gas pedal; it's totally intuition thing, as you should allow a lot of air inside (held gas pedal) but reducing it as engine starts picking up. Should smoke some, but then it will all clear.
As I do not quite believe it worked fine 6 weeks ago, and then fuses blew from sitting. Or pump went bad.
here's a wild thought.
1. car set for longer time - no fuel in fuel lines.
2. attempting to start now - allow some time for fuel pump to build up fuel pressure.
3. if that was not done - as a result, you try starting flooded engine now, as it did not catch right away, then plugs got sprayed with unburnt fuel, wet, and flooded
4. as a result, you either start engine in "flooded" manner, or remove spark plugs, crank engine with starter few turns, and let fuel evaporate through plug holes. In between, take propane torch and burn plugs clean. reinstall, let pump prime the engine, and try restarting.
Even several plugs cleaned that way may start the engine, and then the rest picks up.
"Flooded" engine starting is: have fully charged battery; press alll the way down on the gas pedal and HOLD, while cranking engine with starter; HOLD; it should, normally, crank, crank, then start sputtering - HOLD- then start catching; the very moment it starts catching, you should start SLOWLY releasing gas pedal; it's totally intuition thing, as you should allow a lot of air inside (held gas pedal) but reducing it as engine starts picking up. Should smoke some, but then it will all clear.
As I do not quite believe it worked fine 6 weeks ago, and then fuses blew from sitting. Or pump went bad.
#5
The engine *almost* catches but still will not start.
Read more: http://www.doityourself.com/forum/pa...#ixzz1sLr6vyul
he prolly has at least some.
Read more: http://www.doityourself.com/forum/pa...#ixzz1sLr6vyul
he prolly has at least some.
#7
Sorry for a delayed response- I got real busy at work this week and just forgot to check in here.
Some other reading I've done makes me think it may be a clogged fuel filter- at least it will be a cheap first thing to check. Not a TON of help, though, since I'm not sure where to start LOOKING for the filter!
Interesting idea about accidentally causing a flooded engine...
Some other reading I've done makes me think it may be a clogged fuel filter- at least it will be a cheap first thing to check. Not a TON of help, though, since I'm not sure where to start LOOKING for the filter!
Interesting idea about accidentally causing a flooded engine...
#8
well, in the time you typed this post, you could have tried my method... Always curious, why folks ask for help, get at least some recommendation/-s, then keep posting speculations, instead of trying them.
#9
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The overvoltage protection relay (OVP) is a weak point for these cars. They cause all kinds of problems, including starting problems. Check your OVP for the known bad part number, 000-540-52-45. If that is the part number on you OVP, get the new updated OVP - replacement number 000-540-67-45. The OVP is behind the black plastic cover on the firewall side of the battery. You shouldn't be able to see it unless you remove the plastic cover. It is silver (aluminum), has a clear plastic flip top on it, and has a tab on the both side of the canister for securing it to the mounting hole.