103 firing order
 

I was in a hurry yesterday replacing the rotor and distributor cap.

i know the firing order..... but is the the Number 1 plug by the firewall or the radiator.

I am guessing the radiator since my car won't fire up.

i should know better

Lee, No. 1 is at the front of the engine toward the radiator. The Bosch distributor cap terminals are labeled. Cylinders are numbered 1 thru 6, front to back.

yes.... i now know that....

here's where i screwed up: the long black plastic piece that fits over the wires on the valve cover lists the order of the plugs back wards... the firing order is correct... but it shows number 1 at the rear.

of course i wore the battery out... trying to fire it.

still no start after getting the wiring correct..

anybody have a wiring diagram for a coil? it seems intuitive with one post large and the other thinner in diameter..... i tried switching out with a spare coil and no luck.... so i am wondering if i have the wiring wrong for the coil...

one side is marked 15, which i am guess is positive... the other side I think is marked 0 for negative..
...
it's been too many years since i had car towed for a stupid dyi mistake.... i would like to avoid that embarrassment


********shoot.... i still think i have the firing order messed up..... i mis-read fred's post.... the cylinders go in order 1-6, front to rear....... i will report back later....


lee

finally got the firing order correct.... still have an idle that isn't quite perfect...must be a small vacuum leak somewhere..

i am going to put some new plugs in...but i doubt if that has anything to do with the idle.

i hope you are jesting.... i have owned a good 7 or 8 mercedes in the last 10 years..and i think i have given the pros less than 600 dollars in that time....

i just have a lot going on right now and am trying to do too much..

.....actually it's the people on this board who keep me afloat.... seriously

Lee, what is the condition of the distributor cap, rotor and ignition wires? I replace the distributor cap & rotor every 30,000 miles. If the ignition wires are original a new set of Beru wires may improve engine performance.

fred my original problem was/is tougher than normal start when cold...and a persistent idle that isn't quite right.

in the past couple of months the rpms at idle were going down to the point the car would stall out (below 500 rpms) at red lights if i did not feather the gas while keeping my foot on the brake.

...so i changed the rotor and distributor cap...because it had been 50000 miles or so.... now the car rpm level is back to normal--- 650 or so.. but it still has the idle problem

i have to check my records, but i think i have wires that are less than 4 years old....

i am going to change the plugs...but i don't think that will fix an idle problem


other than that....the car runs great on the open road...

...oh it's still a little balky at cold start up... but it can't be the cold start injector... it's 75 here in South Florida...

seems to me...more and more like the hoses buried under the fuel distributor..

can't find any leak source

Enough Said . :rolleyes5

smiling
 

Maska...you ought to ride in the w140 that we have.....it's a real grown ups car

.....and once again...I am truly grateful for all of the grown ups on this board for the last 9 years I have been here

I have an 88 300CE and have experienced the low idle (500rpm or less) and hard start. Replaced the OVP relay and it solved it. The fix lasts about 2 years, then replace it again.

thanks...i keep a spare in the trunk and i will switch it out....actually, i will switch it back.....

i appreciate the positive input.

Lee, when was the Oxygen sensor replaced last? I have experienced balky acceleration and weak idle with an old Oxygen sensor.

Oops ... my mistake asking about the distributor cap and rotor ... that's what started this thread.

thanks fred...i replaced the o2 at about 100k...two years ago... it now has 123k....

we will get there... i will switch out the ovp today with my spare