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Discussion Starter #1
My daughter bought this A170 without consulting me.
This car will crank but not start for many tries.
After about 20 tries it tries to fire but takes another 10 or so with an occasional cough and then suddenly it fires right up into healthy running.
Once it's warm it starts normally.
Mechanics changed the fuel pump at great expense but no change in the fault.
I've just replaced the plugs with iridium ones and it's the same.
I'm tempted to remove the coil packs and check resistance on the leads as maybe they have out of spec resistance.
This could change as it warms up perhaps?
Otherwise I'm thinking there must be a cold start function possibly programmed into the ecu.
I noticed it had one fault showing on the diagnostic.
 

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Discussion Starter #2
It is POO72 Ambient Air Temp Sensor Circuit Low. [POO sounds about right.]
I'm thinking a sensor might be telling lies somewhere but which one and where the hell is it?
Or even a bad fuel problem as it stinks sometimes when you start it, like old bad fuel smell.
I've just driven it for 10 hours and ran injector cleaner through and one tank of 98 and one of 94 so the fuel should be OK.
I also gave it an Italian Tuneup for most of the trip so cobwebs should have all been blown out. It revs too high in top gear doesn't it? Needs a 6th gear I thought.
. This has only 107K Kilometres on the clock so barely run in but there seem to be a large proportion of these for wrecking in the for sale sections of Gumtree and Carsales.
Could I be looking at a faulty ECU perhaps? Maybe a dry solder joint somewhere in there?
I am very surprised to see it mounted on the hot top of the engine where it gets well shaken about constantly and is constantly almost too hot to touch. For sensitive electronics? Were they planning some obsolescence there?
Bottom line, does anyone have a good time with these units ?
Any advice would be gratefully received and considered.

Cheers.
 

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Maybe too simple but... couldn't just be a faulty battery? I just bought a cheap 2007 A160 Cdi and it was sluggish to start. Swapped in a bigger newer battery and it's much better.
 

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Discussion Starter #4
No probs with the very recent and expensive battery. It was turning the little thing over fast and even had grunt by the end of a few very long stints before the thing would finally fire.
But anyway folks , thanks for all yer help. I replaced the fuel pump relay and she's now starting perfectly.
Now to sell it before something else fails as it's designed to do. I mean $1250 for a fuel pump? And no external fuel filter? ECU getting a joy ride on top of the airbox where vibrations and heat are at the max? Designed to break and cost the earth. See yers later trendsetters.
 

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2005 A 170 Avangarde
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When you purchase the three pointed star, maintenance and repairs can be expensive. However, because your service folks diagnosed the problem in regards to the fuel pump as opposed to the relay, whose fault is that? What you get with that little star is what we call here 'the meter of life', IOW if Lord forbid your daughter is in an accident, nothing protects her like a Benz. Your call on disposing of it. As for the fuel pump, perhaps you should look up what it takes to replace it, it's in the fuel tank and the filter is on the pump, inside the tank. Perhaps you should look for a good Cortina as a suitable replacement.
 

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Discussion Starter #6
Upgraded to a Toyota Camry. 😊
I'll respond about the car though. First why did they give so little room between engine and radiator? I have bruises and contusions on both arms from changing the spark plugs. That's not a user friendly design.
Second, I've changed a few intank pumps on other vehicles, Peugeot and Astra. Dropped the tank in the last Pug and that made the job heaps easier.Maybe a 3 hour job. But the issue with the merc is they don't give an external fuel filter, except for countries with very low quality fuel. Sorry but this is why fuel pumps don't really last much more than 100,000K's where they should last three times longer if protected by another proper filter. Intank pumps have filters, yes but they are very small inadequate gauze numbers as opposed to a big inline high pressure type like I have on my Peugeot. OK the other thing about the baby benz is it's really uncomfortable on anything but a dead smooth autobahn. It's worse than my 4wd Frontera which I thought was a bit rough from a crude suspension.
As far as being very safe I believe you. It's been particularly safe for the 6 months my daughter had it as it refused to start most of that time. You can't get safer than parked in the driveway. Not sure about the stats on them versus Toyota but they are probably not far apart. I'd be interested to see those figures.
Anyway I have now noticed that there seems to be a bit of bearing noise coming from the manual gearbox and upon reading the interwebs I find that it is likely that the box has never been properly filled causing premature probs.To even find the drain and filler I now have to jack the car and inspect from below, no I don't have a hoist, so yet another very unfriendly and potentially final problem has been laid on this vehicle for no good reason I can see except designed obsolescence.
As is the ridiculous position of the ECU on top of the air box where it gets max vibration and heat. Most manufacturers put these electronic sensitive units in rubber mounted capsules protected from the main heat under the bonnet and they rarely fail when given the cotton wool treatment. Given the enormous expense for replacement it appears to be reckless irresponsibility on the part of MB to endanger this component in such a way.
These are my gripes after having the car for 4 days. Just the things that screamed at me, and I am amazed that people go to great lengths to keep these things going. Without Lofty of course you guys would mostly be sunk.
So good luck with it all and I hope you all get huge mileages and many pleasant hours on the road with all of Lofty's great community service to y'all.
Cheers.
 

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2005 A 170 Avangarde
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You need to contact Daimler and offer your services as a design and QC expurt.

Daimler AG
70546 Stuttgart
Germany
Phone: +49 711 17 0
Fax: +49 711 17 22244
e-mail: [email protected]
 

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1986/1990 W126
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This thread gave me a chuckle. Good points all round :ROFLMAO:
 
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