Cold start probs (560 SEL)
 

Hi,

It's been around -5 to 0 degrees Fahrenheit the past few evenings.

When my wife leaves the hospital late at night (parked in an unheated ramp for 9-10 hrs.) it takes 3-6 cranks to get it started. Once running, it runs smooth as usual. No smoke or drama.

It starts fine at home in our 45-degree garage.

I asked her to imitate the sound and it doesn't sound like a dying battery, so I was thinking that it's a possibly a failing cold start valve? Probably not the OVP, since the car runs like a champ after it turns over. Smooth revs, no smoke etc.

It's going to warm up later this week, so I'll try to simulate the conditions early tomorrow morning by parking it outside.

Thanks for any ideas.

Does Mercedes use a cold start valve? If so thats where I would start. I often had this same trouble. Thanks

Hi w126,
do a search on cold start or cold start valve.
There is a lot to read. You can also see how a cold start valve looks on Fastlane under the fuel injection heading.
Good luck and dress warm tomorrow...
Reinhard Kreutzer

maybe its time for a good tune up .....after this, ...it will be easy to troubleshoot.

It did it again last night and my wife doesn't give me a good description of what it does, so I said screw it-- the tank is going into the shop Monday.

It's hard to diagnose something when you rarely drive it. I started it this AM in the 43 degree garage and everything was A-OK.

I think it's the battery and my first hunch is usually right. ;)

Well, it's in the shop, but they are having a tough time duplicating the problem and the car *did* sit outside of his shop for 8 hours in -1 F weather -- it started on the first "twist" early this frigid morning.

Odd...

He said the OVP is really "hot" to the touch, so that maybe something to go with. :confused:

OVP replaced, will see what happens. (talking to myself again ;) )

nope I'm still watching the thread

Thanks Dan,

Well it was cold last night, around 8 F and she started right up after sitting in the ramp for 9 hrs (per my wife).

First "issue" I've had with the car in a few years of ownership, not too bad.

I had similar problems, when eventually the hard starting got so bad that it refused to start. I checked the OVP (which seemed fine), checked out the Cold start valve (checked OK), replaced the feul pump check valves, changed the plugs and plug wires, replaced the fuel pump relay, and the problem keeps coming back to haunt me. Now I am thinking of changing the fuel injectors, and if it still has problems I am gonna take it to a shop and have them diagnose it for $250.

Sohaib

89 420SEL

Sohaib,

I was just about to mention the fuel pump relays, but then re-read your post. Hmm... scratching my head here.

When you say you checked the OVP, what did you do. Mine was quite hot to the touch, so it was replaced. Not exactly expert troubleshooting, but it seemed to do the trick.

Makes sense to replace the injectors, but how many miles are on the car and how cold does it have to get to cause trouble?

This may sound overly simplistic, but did you test the battery and check the condition of the cables? Are the terminals clean etc??

hey at least you got it figured out :D

Hey Ted!

Long time, no talk!! Saw your post, and I'm glad to hear that the ol' 560 is starting the way it should again!!

My 190e is out of commission right now - hit a deer on 12/29, and the body shop is fixing the $7k worth of damages! Unbelieveable.

Hope all is well in Madtown!

Take care-
Michael.

Hey Michael,

Sorry to hear about your 190! :( Did that happen in WI or IL?

Don't fret, you'll be back on the road soon!!

Argh, is this a Jaguar in disguise?
 

Problem not solved. Car sat for 11 hrs. last night at the wife's work. Temp was 12 degrees, took about 6 cranks to start. (these are the details she gave me)

Odd thing is that I let it sit outside for about 8 hrs, in colder weather and it started no prob. pre new OVP 2 wks ago.

Battery, connections checked out OK and has a new OVP.

Maybe I should get the '69 Caddy out of storage and she can drive that! :rolleyes: