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thegowerpower
Wednesday 12th April 2017, 13:24
Hi All,

weird problem i just had on my 1999 Volvo C70 t5 manual.

So the battery died the other week as currently selling the car, battery is only about 6 or 7 months olds from halfords.

Problem is that i charged it up fully, stuck it back in the car and then started her up, started fine but had a weuird idle and the throttle would not work, nothing at all. i left it for a week or two as i was workign weekends,

Next think i called the breakdown and got them to have a look, the recovery guy wasnt really listening and i was explaing what had happened, he stuck his booster back on and then started it up , it now burst into life and then was workign as before.

So i let it run for ages and didnt turn it off, I then got backl to the house about an hour later and then turned it off.

I then turned it back on to put it on the drive and no juice in it, i then charged it again and then put it on the car and it starts again but again, the throttle is not working.


Do you think the battery is fecked?

any seen this problem before?

- I was just going to get another battery for like 40 or 50 quid to try as i have no spares and cant even get a second hand one anywhere to test.

any help much appreciated,

Thanks

LeeT5
Thursday 13th April 2017, 07:14
Firstly, Why did you remove the battery from the car? Are you not able to charge the battery with it in situ?
Secondly, Who was the breakdown company that attended?
...and lastly, if you had the car running for an hour (assuming it was charging ok?) then removing the battery, charging and refitting (Bad idea) and then it starts...would suggest, to me, that your battery is knackered and so badly sulphated that it can't hold a charge properly.

When you say...."the battery died last week as currently selling the car..." I guess what you mean is, I've not been using the car for weeks, at all and I've let the battery go flat!?

By removing the battery from the car - that is mistake No1. Now the ECM and other modules have all lost their 'learned' settings and will, by default, revert back to base/stock settings that were first programmed into them. Problem is, your throttle assembly is probably so dirty and contaminated with carbon, that the ECM cannot operate the throttle because it's outside of ECM limits of operation as it's so dirty.

This is the exact same senario that happended to me once, when I accidently removed the battery earth without a power saver fitted on a 1999 V40. :slap:
I'm assuming that you're NOT touching the throttle when you turn the key to start? If you are, you're not helping!

The only way you will get that throttle working again is by doing the following:


Firstly, either fit a smart charger to the battery and leave it connected until you can get the car started OR replace the battery for a new one. If you can't park near the house, then I suggest the latter.

Then you'll need to Decoke/clean the Throttle assy on the car until you can see your face in it! It needs to be spotlessly clean, no Carbon or dirt, especially around the throttle flap hinges and edges of the flap. If you can remove the Throttle assy, this will make it easier and thorough, otherwise, use a big screw driver to hold open the flap while you use a lint free cloth and Carburettor cleaner to degunge the throttle. If the Throttle assy is really dirty and caked in Carbon (which I suspect it is) then you must remove it, otherwise all the carbon and Carb cleaner will be washed into the manifold/engine.
Once clean, refit checking everything is connected as it should be. Double check....you don't wanna leave anything unplugged!

Then you'll need Good diagnostics as your going to need to reset the Adaptation settings in the ECM for the throttle. Once you do this, clear any fault codes present and then you can start the car....making sure you DO NOT TOUCH THE THROTTLE when starting the car!
If the throttle still does not work at this point, then I'm afraid your probably looking at a faulty throttle potentiometer ('fly by wire' throttle pedal). You should have a fault code stored for this, so check!

If you cannot do any of the above then I suggest a friend who can or get the car recovered to a garage.

jdavis
Thursday 13th April 2017, 08:04
Good advice Lee