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Discussion Starter #1
Car Details: 300ce M103 Engine 12V Automatic.

Recently I have had a new Flywheel and Starter Motor fitted as I had starting issues.

Work was done after 3 weeks as I was finding a flywheel which took ages and all this time my car was parked up through the terrible snowy weather. There was no antifreeze in the car.

Anyway when I got the car back I noticed that the idle is really low - just below 5,000RPM when it used be at just under 1,000RPM before. It rumbles at a standstill and even cuts of and have to restart. I'm having to break with left foot and keep revs built up when driving by shifting in Neutral when braking otherwise it would just cut off. :confused:
While the car is driving it is fine. Runs smooth and pulls well.
Also when starting in the mornings it just about starts I have to keep pumping and pumping the accelerator till it starts. Sometimes my battery dies down and have to jump lead. It takes ages to start sometimes up to 20mins.

The mechanic said my core plug had a small leak in it which I have bought BUT i am pretty sure this has nothing to do with the starting problems has it?

ANyway please help!!! :confused:
 

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93 300E 2.8, 79 450 SLC
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539 Posts
When my MAF (mass airflow sensor) was bad, the car idled badly but drove fine most of the time. The engine check light also on when the MAF was bad.
 

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W124 Moderator
86 190E 2.3L 16V, 2 95 320TE's, 02 S500
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12,744 Posts
If you have an M103 motor in the CE, then you do not have a mass air flow sensor to check. Normal idle on this motor should be 550 - 650 rpm. Idle at 1000 rpm is way to high. I would check you OVP relay first.

Good Luck,

Jayare
 

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2008 E350 4M, 2016 Audi Allroad, 2019 Audi Q5
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5,445 Posts
A core freeze plug has nothing to do with starting issues.

I think you have some vacuum leaks so go ahead and replace all the idle control vacuum hoses attached to the idle valve. That is the poor starting, the high rpm could be a stuck idle control valve (you'll have it almost out anyway when you replace the hoses so shoot some carb cleaner in it) and replace the OVP.
 

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Discussion Starter #6
I have found out that if I spray Carb Cleaner while starting it works. Car starts!!

All day I have no problems but then I have to spray carb cleaner in again when it doesn't start.

And another weird thing - I am getting better MPG. Almost 30mpg - before was about 23mpg.
 

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W124 Moderator
86 190E 2.3L 16V, 2 95 320TE's, 02 S500
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12,744 Posts
I think the car is running exceptionally lean if you are having to shoot some sort of starting assit to get it running. Use the search function of the forum and read threads on "air/fuel ratio adjustment". I would also check that both of your fuel pumps are working.

When you can, complete your profile. It's very helpful and

Good Luck,

Jayare
 
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