car hard to start but alternater is charging battery

[dragonslayer]

hi guys ive got another problem.the car is hard to start sometimes.like the battery is dead.but i jump start it off another battery not another car its ok.and tested the alternater and there is current goingto the battery charges ok.
what can be wrong? im stuck.sometimes its ok
please help
dave

[moonshinespecial]

how much current is going in ?
test whilst it is running then switch everything you can find on and test again .
the voltage should go up to 13-14 volts when putting a charge in .
also see what the voltage drops to when you try to start , maybe you have a cell down .
another possibility is a sticking starter motor .

[Longintooth]

Hi
Since it starts with another battery you can probably rule out the starter motor as a fault. The alternator voltage is important since unless you have 14.2v there will be insufficient pressure (volts) to push any current through. Using a clamp on ammeter, you can measure the charging current on no load. Just after starting it will push in approximately 20 amps and then start to reduce to about 10amps then on to float charge 5amps or less. Just because your alternator can push out 60amps does not mean your battery will accept it at 14.5 volts since it has to overcome EMF in the battery and that requires higher volts. Modern alternators use smart technology to give longer life to the battery ( my HDI with 85,000 miles and reg 2000 still has the original battery) very clever stuff. Turning all the accessories and lights on puts a load on the alternator and it should match any load you put on it - it proves your alternator can deliver since this is what powers everything once the engine is running - not the battery. Make sure the belt is adjusted correctly and is not slipping. Get hold of a hydrometer from your local motor shop and test each cells specific gravity - they have coloured bars on for the layman. The value should be about the same on each one and in the green. Another more elaborate test is the heavy rate discharge tester that can test the amount of current it can deliver over a short burst.

If the electrolyte is very dirty it is a sign that the plates are heavily sulphated and that it is near the end of its life. It is possible to ressurect them with a conditioning charge using an off the car charger - it is a short burst of high current followed by a regulated slow charge.
You may get lucky.

[steve_earwig]

Did you do test the alternator output with all the lights etc going? Run the engine at about 3,000rpm with the headlights and heated rear window going, after about 5 minutes when things settle down you should be looking at about 13.5 volts across the battery.

This time of year generally puts a strain on batteries - windscreen wipers, lights, heated rear window, heated seats (if you have them ) - so there's always the possibility that a short journey won't put enough charge back into it to start the engine next time from cold (random fact: a cold battery has less charge in it, in some very cold climates they have to warm the battery before it'll start the engine, which they also have to heat). Or it's lost a cell and just isn't holding enough voltage to crank a cold engine. Next time it doesn't start see what the voltage is, don't crank it over for ages, rush straight out with your meter (I presume you have a meter because you tested the alternator output*). It would be nice to test the electrolyte but most modern batteries are sealed so you'd need a drill to get to it (not advisable).

If the battery is lacking in voltage it still could be for a number of reasons, no. 1 is of course a duff battery, but it could also be you've got a leak - either there's a short circuit to earth somewhere or something's on that should be off. With everything on the car turned off unclamp the earth from the battery (8mm) and put your meter on it's high current range between the earth post and the earth clamp, if the current indicated is anything above a few milliamps then this could be the problem and it's deerstalker time.

Other things to look at - battery & alternator connections.


(*You need a meter of some sort, otherwise diagnosis is guesswork, digital multimeters are getting cheaper all the time and beat test lamps (and guesswork) hands down. )

[Longintooth]

Hi
Once the engine has started the battery has little input to the system - the alternator takes over at about 700rpm and should be pushing a healthy 10amps or more at 1000 rpm otherwise it does not matter what you turn on - winter or summer except the occasions when at idle when there may be less current generated than you are consuming. If you find yourself sat in traffic at idle for long periods turn off unnecessary equipment - especially heated rear screens, heater fans, headlights etc. Be very careful not to disconnect the battery when the engine is running since this will blow the surge diode in the alternator rendering it useless. If you don't have any test equipment a simple but effective test for the alternator performance is - start the engine in the dark, turn on all the electrical load and observe if the lights get brighter when you lift the revs with no squealing from the drive belt. If so the alternator is oK. There are some things to check here - if the ignition light glows very dimly at idle, one of the diodes in the alternator is defective yet it could still lift the lights a little. Invest in a cheap digital multimeter - it's more than worth it. Almost all alternators should accurately regulate the volts at 13.9 to 14.2, any less than this can make a big difference to the state of charge of the battery, especially in winter when temperature affects the battery performance. Good practice is to insulate the battery as much as possible, when starting with a suspect battery select neutral, keep foot off the clutch, make sure all other equipment is off. However, to avoid disruption, do the battery tests first. The only items that should take power when parked up are the clock and security modules which consume only milli amps.

[Longintooth]

Hi Steve

It would be nice to test the electrolyte but most modern batteries are sealed so you'd need a drill to get to it (not advisable).

I was reluctant to suggest it to a layman but I have done it on low maintenance lead acid batteries with a degree of success. However it's a waste of time with Gel batteries for obvious reasons. I just looked at mine and see it is indeed sealed - no caps under the label but my much later BMW has still retained the caps for inspection. I just called my local supplier who said most of the replacements they sell are still with caps especially the heavy duty commercial.

I think he has enough to go on with.

[dragonslayer]

cheersguys allfixed it was a loose connection on the wiring going to the battery now charging at 13.4 to13.5 so looks good
bought new clamps and soldered the wiring and screwd the wiring tothe clamps and jods a good one
just got tofind the hall sensor pick up now for the rev counter and the coolant temp sensor
cheers dave

[Doggy]

I think you're looking for the crankshaft sensor, it's an inductive pick up which senses the reluctor ring on the flywheel & is located, 'on the front face of the clutch housing', according to Haynes.

There are, I understand, several coolant temperature sensors, with different uses, (fan control, temperature gauge, sensing for ECU). Do you know which one you're after, or what problem you're aiming to resolve

BTW I had a spell of rev counter problems, lights flickering etc which all cleared up when I changed a dodgy battery - fairly sure it had an intermittent internal connection, as it was really hot when it packed in, so similar to your loose connection above.

[dragonslayer]

hi are all the sensors on the thermostat bit im looking for fan control and coolant sensor as i think they are messing around a bit.as the fans work but not come on as qick as they should.ill give them a clean if i can find them
cheers

[Nicodemus]

are all the sensors on the thermostat bit im looking for fan control and coolant sensor

If you can be bothered to do a search you'll find quite a few posts about the coolant temp sensor on the thermostat housing and refilling/bleeding the coolant since the cabin heater matrix is a tad higher than the thermostat and you need to avoid airlocks/entrained air in the coolant system.

There are answers to most if not all of your questions allready on these boards, if as I said, you can be bothered to search for them instead of expecting others to do it for you.

[dragonslayer]

are all the sensors on the thermostat bit im looking for fan control and coolant sensor

If you can be bothered to do a search you'll find quite a few posts about the coolant temp sensor on the thermostat housing and refilling/bleeding the coolant since the cabin heater matrix is a tad higher than the thermostat and you need to avoid airlocks/entrained air in the coolant system.

There are answers to most if not all of your questions allready on these boards, if as I said, you can be bothered to search for them instead of expecting others to do it for you.

ok point taken its just im newish to the site so bear with me and i have never owned a peugeot before
dave

[DaiRees]

are all the sensors on the thermostat bit im looking for fan control and coolant sensor

If you can be bothered to do a search you'll find quite a few posts about the coolant temp sensor on the thermostat housing and refilling/bleeding the coolant since the cabin heater matrix is a tad higher than the thermostat and you need to avoid airlocks/entrained air in the coolant system.

There are answers to most if not all of your questions allready on these boards, if as I said, you can be bothered to search for them instead of expecting others to do it for you.

ok point taken its just im newish to the site so bear with me and i have never owned a peugeot before
dave

Don't worry about Taxi Dave, it was his time of the month, he'd forgotten his pads and he ended up having to pay his own soiling charge..... where's that bloody "barf" emoticon??? He's better now though

PS: The Search box at the top right is your friend
PPS: The prieview button's quite a handy chap to know too, I've been glad to be aquainted with him on several occasions.
PPPS: Only joshing Taxi, none intended

[Nicodemus]

PPPS: Only joshing Taxi, none intended

No worries.

ok point taken its just im newish to the site so bear with me and i have never owned a peugeot before
dave

Folks are less likely to answer a post on any forum if the same question has been asked a number of times before. It's in your interest to do a tad of homework and yes mate, a Haynes BoL is worth getting.

[Welly]

I find the search box tedious at the best of times

If you want to know what's wrong with 406's just click on my name and go "find all posts by Welton"

[Longintooth]

Hi
For the benefit of others on this subject with winter coming on fast, this is the time to make sure your Electrics are in good order. Just a small but very important point - the voltage across the battery terminals should be a minimum at idle of 13.9 -14.2 -13.5 is not good enough, however, because it is a smart regulator you will get 14.5v +/- .05v even with a load applied at ambient temperatures of 10C as a guide. But if you are not getting this there is something amiss. The regulator detects the battery voltage and current passing and decides whether to apply a little more voltage than the optimum. If you hook up a smart external charger they are even more sophisticated and will lift the voltage to 15v if it detects that the battery is below an accepted state of charge, then it will progressively reduce this as the charge come up until it assumes a float charge that flicks in and out to maintain the charge. A trickle charge can be applied that applies a constant small input. Going back to the car alternator - and normal use, the battery condition deteriorates as it ages and so the alternator monitors the changes and uses over voltage to push in current to get the cells fully charged so unless it achieves this during cold periods the battery output capability is reduced and therefore to offset this the alternator voltage has to compensate. It figures that a very cold battery voltage may drop to 11.5volt if allowed to stand for some time and this may be insufficient to drive enough current to the starter but 12.5v will make all the difference. Warning some starter chargers will increase the voltage to 16v to get 300amps flowing through to the starter - if this is allowed to happen without the motor drawing the current it will reduce the life of the battery significantly and boil the electrolyte.

So if you want a trouble free winter -14.5v at idle or minimum 14.2v.