Help I have a w114 250ce 1971 the problem I have is that the car will start and run fine whene cold but as soon as it get up to temptature it splutters and runs like a bag of sh++t I have also just pute in new spark plugs,plug leads,dizzy cap,roter arm, no joy dont want to pute into a garage for some thing silly so please please all help needed regards Ray.
W114 250ce
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Help I have a w114 250ce 1971 the problem I have is that the car will start and run fine whene cold but as soon as it get up to temptature it splutters and runs like a bag of sh++t I have also just pute in new spark plugs,plug leads,dizzy cap,roter arm, no joy dont want to pute into a garage for some thing silly so please please all help needed regards Ray.
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Hello and welcome,,you do not mention the coil, these when hot can slowly reduce the spark to almost zero. lift a plug cover and use an insulated screwdriver with the blade in the cap, and hold it ½ inch away from any metal part of the engine, there should be a good fat spark. gauges to test this are cheap
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Yes injection D I think
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Thanks for the replys,should have said car is injection.and looks like a new coil has been fitted,only had the car 4weeks ran fine whene I viewed it drove it home to Liverpool about 50 miles no problems then a week after that its just went down hill from there and seems to have gon from bad to worse and Iam starting to lose all faith in the car now
Is it still on points?Worth replacing along with the condensor.
Along with the above,you should also check the diaphragm in the fuel pressure regulator.
Finally,the poor old thing is nearly 40 years old,surely it's allowed the odd senior moment.
Along with the above,you should also check the diaphragm in the fuel pressure regulator.
Finally,the poor old thing is nearly 40 years old,surely it's allowed the odd senior moment.
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Also check the green wire from the dizzy to the ignition module!!!
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If you find that the coil is OK then the next step would be to check the injection system. There are a few good books on D-Jet out there, which would allow you to diagnose any problems with the various sensors. I think one of the books is published by Bentley.
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popuptoaster
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they have a diagnostic port on as well if its the same as my 280, god knows if anyone can read em these days though. nice choice of car though.
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this might help http://www.scribd.com/doc/7303245/D-Jetronic good luck & post some photos when you get the chance
they have a diagnostic port on as well if its the same as my 280, god knows if anyone can read em these days though. nice choice of car though.
It was more of an information gathering point for the tuning variables,battery voltage etc.
I was hoping to go up the farm & take a look at mine last weekend,but I've got work coming out of my ears.So from memory,I think that there's a second set of points under the advance mechanism in the dizzy which send a firing signal to the injection ECU.As I recall they were of the cartridge type (ie;not adjustable).Would be worth a check.
Also,you say that it looks like a new coil-any other new parts been fitted before you got it?
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A igntion coil is only a primary with a few turns of wire, and a secondary with about 15k turns, one short turn and the thing will slowly heat up, to the point that in after about 5-10 mins the secondary high voltage will be almost nill.
You cant measure 1 short circuit turn on a meter.
The condenser plays an important part as well, when the points are open, it act as a gate apposing the induced voltage from the secondary. 12 volts coils need a 2.2 mfd cap, 9volt 3.3mfd and 6 volt 4.7mfd all 250volt dc and 500volt ac working
You cant measure 1 short circuit turn on a meter.
The condenser plays an important part as well, when the points are open, it act as a gate apposing the induced voltage from the secondary. 12 volts coils need a 2.2 mfd cap, 9volt 3.3mfd and 6 volt 4.7mfd all 250volt dc and 500volt ac working
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Hi again has new points and condenser my only problem is that I dont know much about the workings of an engine I know a little such as points and plugs but Iam afraid thats about it so I will plod on for now wiggling this and that might get lucky (but I dout it) I think I will have to end up selling her as its doing my head in?.Regards Raymond
The reason I asked about the points is as follows.
A frequent 'mistake' that is made when changing the points on the older cars is to replace the shouldered bolt (because it snapped,threads stripped etc) which goes through the dizzy body (for the 12v supply to the points) with any old bolt.This then gets tightened up a bit too much resulting in the low tension circuit making contact with the dizzy body.This can manifest itself in many ways;a plain old non start,missfires,cutting out when warm etc depending on how good a contact is being made with the distributor body.
Also whilst checking this,check the condition of the plastic insulator piece that this bolt runs through.They deteriorate with age giving similar problems.
A frequent 'mistake' that is made when changing the points on the older cars is to replace the shouldered bolt (because it snapped,threads stripped etc) which goes through the dizzy body (for the 12v supply to the points) with any old bolt.This then gets tightened up a bit too much resulting in the low tension circuit making contact with the dizzy body.This can manifest itself in many ways;a plain old non start,missfires,cutting out when warm etc depending on how good a contact is being made with the distributor body.
Also whilst checking this,check the condition of the plastic insulator piece that this bolt runs through.They deteriorate with age giving similar problems.
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Ok I give in with this car so if anyone wants to make me a sensible offer I think I will just sell her the body work is signal red front wings in very good condition as are the doors all in all good condition for age of car.
jibcl500
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Ray
where is the car and how much do you want.
jib
where is the car and how much do you want.
jib
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Hello again had someone come and have a look at the car today,had a play about with the pressure sensor big screw in a bit out a bit at did make a big differance but could not get it spot on faulty sensor? and if so where would I get one merc quoted £800.
