300 es auto hard starting

1994 300 es auto not fly by wire edc. Sounded like battery on its last legs but always started. One day needed to jump start,fired first time,so changed battery.Now it churns over and rarely starts,jump leaded off wifes car ,started first revolution.Heater plugs work ,will only start when i
jump it. Starter sounds ok,problem only when vehicle is cold,ok when warm.Heard obout fuel line pourosity,is there an access panel in the boot floor to check them out.I have posted on other forums as this is driving me mad having to carry a spare battery and jump it when i go to and from work,always in the rain or snow.

If it starts ok when you jump start it, there can't be a fuel problem.

I reckon it's related to the replacement battery - did you fully charge it before installation?

No,it seemed alright,i will put it on overnight,it gives the impression of a failed cold start sensor,but i take it mine does not have one,or does it.If it is not edc,then would it?

If it starts ok with a jump start, your fault must be battery / connection related.
When you jump start it where exactly do you connect the jump leads on your car.

bishen67 said:

No,it seemed alright,i will put it on overnight,it gives the impression of a failed cold start sensor,but i take it mine does not have one,or does it.If it is not edc,then would it?

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Iirc a non-EDC car doesn't have sensors but the pump will have a cold start mechanism.

But as I said before, if it starts ok with jump start, it's battery or connections. Don't honestly think it can be anything else?

Spare battery to the car battery.Or wifes car battery to my pile of s**t battery. I presume you mean this.

I will give it an overnight chrge and see. Thanks

bishen67 said:

I will give it an overnight chrge and see. Thanks

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Before you start to charge the battery, disconnect the negative terminal (assuming you have the radio code??). It will protect the car electrics whilst charging the battery.

bishen67 said:

Spare battery to the car battery.Or wifes car battery to my pile of s**t battery. I presume you mean this.

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Try cleaning the battery terminals and the inside surfaces of the battery clamps to shiny metal.
By connecting the jump leads as above you are bye-passing your own battery connections.
Also, have you ever cleaned the chassis connections on the two engine earth straps, if not they will be corroded by now and due.
If you need details let me know.

Cleaned the battery earth on the chassis and the one on the starter,and the bunch including the glow plug relay by the battery. are there any more ?

bishen67 said:

Cleaned the battery earth on the chassis and the one on the starter,and the bunch including the glow plug relay by the battery. are there any more ?

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If you've done the two connections to the chassis thats all you need for starting.
If you need to, the main body earth is behind the battery on to the inner wing top but that won't affect starting.
If you've also done battery terminals and no better starting you're only left with the battery.

If you need to check for air leaks into the fuel lines have a look under the access panel in the rear of the boot floor. The two elbows on the top of the fuel sender corrode. If ok clean and paint and cover with a lot of grease.
If corroded badly they perforate and let in air so usually need repaired or replaced.