1990 300se No Cold Start
 

Purchased this car back in June. Drove appr.15 hours non stop to pick this car up and get home. We started driving this car and the first issue was no power. After a week in the garage and one gutted catalytic converter later ,everything seemed ok until the temp drops below 50. Then the car has no intension of starting and unfortunatly we did not intend on parking it for the winter. So being that I read some of the other threads on similar problem I tried changing the 4 pin controller on the far back driverside of the head. Ofcourse this didn't help. I see two more temp senders of some sort infront of the one I changed. My main Question is where is the best place to start in trying to figure this out. The car cranks real strong(new bat.). Also I am getting fuel to the cold start valve. I got enough fuel in it that after tring to start numerous times and the outside air warmed enough I blew the seem out of the back muffler. Good thing it was not a benz muffler. The ovp relay does not rattle, and it has spark. Help I am desperate the wife is hinting on bringing the car in and throwing me out:) . Thanks (1990 300se 3.0 I 6)

How cold is it where you are?
Do you have a multi-meter with duty cycle setting?
Anti-lock brake light on?
Can you spray ether in the intake and get it to turn once or twice?

It is only 30 outside right now, no anti lock light on, didnot try either yet. Was thinking about checking the boot under air intake valve, but that will wait till tommorrow. Do not have meter with duty cycles

Well if the ether works it's probably not electrical... if not then does it jump start... alternator and battery (how old is it...) test... Sears has a good cheap multi-meter with duty cycle that you can use to check lots of stuff with. Post your preliminary results and youll get more guidance... probably from someone who knows more than me. When you try stuff try and remember or write down and post as many specifics as seem they may have any relavance as this helps those who have 'seen it before' recognise it faster.
Good luck

I should have explained more. Added to first note. Cranks fine seems like plenty of fuel. It seems like there is no spark but when I pulled all the plugs. we cranked it to clean out residual fuel(it smelled flooded) the thing blew muffler apart