M103 1992 300e spark problem anyone know??
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2001 CLK w208 200 kompressor. 1992 w124 300E
M103 1992 300e spark problem anyone know??
Hi my 300e suddenly won't start, it ran just fine and suddenly it stopped. i have been browsing forums but i dont find anything that is just like this.
i have checked injectors they are fine and the fuel relay is fine and the fuel pump is fine and the ovp relay is fine.
The spark plug wires is new and distributor is new. I checked coil and ezl and cps and they ar all good on ohms. but the thing is that my spark plugs only spark once. the have a good blue bright spark but all cylinders spark once. i dont understand why.
Another thing i noticed is when i crank the engine the rpm needle goes up and down between 500rpm to 1500rpm even tho the engine spins at same rpm. Is this the cps that is faulty?
Thanks for reply sorry for my rubbish english
i have checked injectors they are fine and the fuel relay is fine and the fuel pump is fine and the ovp relay is fine.
The spark plug wires is new and distributor is new. I checked coil and ezl and cps and they ar all good on ohms. but the thing is that my spark plugs only spark once. the have a good blue bright spark but all cylinders spark once. i dont understand why.
Another thing i noticed is when i crank the engine the rpm needle goes up and down between 500rpm to 1500rpm even tho the engine spins at same rpm. Is this the cps that is faulty?
Thanks for reply sorry for my rubbish english
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2001 CLK w208 200 kompressor. 1992 w124 300E
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2001 CLK w208 200 kompressor. 1992 w124 300E
If that is the case i have checkt it. I made one of those pulse counters and i got 13 flashes and 33 flashes. I may have counted wrong on 33. Mabye it was 34 flashed. And again sorry for my bad english :P hope its understandable
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2001 CLK w208 200 kompressor. 1992 w124 300E
Not gone yet :P just long shifts at work so havent had time. But i did look a bit at it today and it suddenly fired on 1 mabye 2 cylinders. It is a real pain to figure out. But i wil run the diagnostic test again. But as i remeber there was only 2 plugs in the contact beside the battery. Is it soposed to be like that, not more plugs for diffrent parts of the car?
And sorry for bad english.
And sorry for bad english.
Last edited by Jorode02; Apr 23, 2016 at 06:17 PM.
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From: Hong Kong
'90 300CE M103 Manual '93 Alfa 164 QV24 '05 Jaguar X350
I experienced no-start situations in my M103 before and each time they had a different cause. The CPS, fuel pumps (not the relay, there are two at the back of the car), and ignition coil.
The first thing to check in any vehicle with a no-start situation is normally the CPS. If a new part (about $40 maybe) is not expensive, or a good used part is available, try replacing the existing one and see if it cures your problem. But before throwing any money into this, back track a little and ask yourself why did you replace the spark plug wire and distributor, and did you replace them both at the same time? My lesson learned is always change these thing one at a time so if there is a problem you know which one is the likely misfit. If you still have the old parts and they still worked before you replaced them, put them back and see what happens. As regards spark plugs, are they also new ones and are they the right ones? Also, before the non-start happened, did your engine bay ever got wet by any chance?
The first thing to check in any vehicle with a no-start situation is normally the CPS. If a new part (about $40 maybe) is not expensive, or a good used part is available, try replacing the existing one and see if it cures your problem. But before throwing any money into this, back track a little and ask yourself why did you replace the spark plug wire and distributor, and did you replace them both at the same time? My lesson learned is always change these thing one at a time so if there is a problem you know which one is the likely misfit. If you still have the old parts and they still worked before you replaced them, put them back and see what happens. As regards spark plugs, are they also new ones and are they the right ones? Also, before the non-start happened, did your engine bay ever got wet by any chance?
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From: Worcestershire UK
W124 260E
Jorode do a check on your crank possition sensor [ CPS ] remove the cps leed that plugs in to the EZL this is the box on the inner fender . Find the cps wire that comes from the flywheel bell housing . Pull it off from the EZL , and check ohms it should be 650 ohms to 1200 ohms ,anything under 650 ohms then its no good.
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From: Hong Kong
'90 300CE M103 Manual '93 Alfa 164 QV24 '05 Jaguar X350
There are several versions of the M103 engine which may have different idling range. The factory idling guide is normally printed on a decal found on the front dam above the radiator. Mine is M103.983, in-line-six 3.0L, 12V, for which the normal idling speed according to the factory guide is 600 - 750 rpm. I rebuilt my engine a few years ago. At normal operational temperature, it now idles steadily around 625 rpm.
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2001 CLK w208 200 kompressor. 1992 w124 300E
The 300 is alive again! It was the new rotor from bosch that was faulty. I was at the junkyard today and found a replacement rotor and it fired right up!
That straight6 is music in my ears!
That straight6 is music in my ears!
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From: Hong Kong
'90 300CE M103 Manual '93 Alfa 164 QV24 '05 Jaguar X350
Congratulations on reviving your 300E! Yes, sometimes the engine is hyper sensitive to minor or inexpensive parts. Using genuine or OEM parts sometimes help resolve or isolate certain problems.
