Non Starting 2.6 Diplomat

[melinx]

Saturday night the Diplomat totally refused to start despite spinning over in a perfectly healthy way

It had been perfect the day before, starting 'first touch' : The temperature had crashed on Friday night to minus 4 and although it is kept garaged -- 'she no start'

Put it on charge and tried again Sunday (temp. down to minus 4 again overnight) 'she still no start' !.

Doing what I have advocated to others on a number of occasions, I put a meter on the battery and watched the voltage during cranking; sure enough it was dropping to 10.88 volts.

Von Opel (who knows about these sort of things ) says that the ECU is specified down to 10 Volts, but wisely adds "but don't count on it".

Had a new battery delivered today (Bosch S5 75 Ah 750 CCA) and sure enough it started, it took a bit of spinning over before she fired up; I reckon that I'd probably got bore wash by then because the exhaust stank of petrol.

The battery which refused to start it (Varta 60 Ah 540 CCA) had a 3 year guarantee and has been on the car for 2 Yrs. 4 months and kept on a non gassing 13.9 Volt max. trickle charge if the car isn't being used for a while.

It's a cracking bit of design to be able to get the battery to clap out that close to the end of the guarantee so I'm not having another Varta hence my going to a 5 year guarantee Bosh

I've just proved to myself again what I said when I had the same problem with the Vectra

http://totalcarlton.com/forums/index.php/topic,9728.msg77888.html#msg77888

I had the Bosch battery from : -

http://www.carbatteriesonline.co.uk/

The one I've quoted is the biggest one that fits my battery tray and cost £70 inclusive of VAT and delivery (it came next day ) which is an excellent price  .

[man of kent]

I always buy the biggest battery. It pays in the end.

[chrismec]

That's a good price for a big battery

[melinx]

Over the past week or so during very cold temperatures, even with the new maximum sized battery, there have been some very difficult starts

A few degrees above zero, first touch it's away: Zero and below, lots of spinning

Although I have checked, cleaned and WD40'd them fairly regularly, I gave all the engine harness plugs another go and found that there was a noticeable improvement

I began to suspect the AFM internal connections were a bit 'iffy' when it got cold so I swapped it for my spare, the result was that it went first touch even below zero !!

Unsealing and removing the cover on the original AFM, I checked the spring connections that I mention in the photograph in the link below.

http://totalcarlton.com/forums/index.php/topic,13208.msg109123.html#msg109123

Checking them with a meter showed that they were marginally less than perfect but using a very small screwdriver and moving them about a millimetre each side of their rest position restored the connection to zero Ohms maybe they were considerably more dodgy in below zero temperatures

I haven't replaced it, I've left the spare on !

[man of kent]

Interesting. I had an undefined starting problem when it got cold last winter. When it warmed up it started. Murph later had the car and had starting problems in the summer which turned out to be the Lambda sensor. My problem starting could also have been a lambda problem when it was cold?

I wonder if your problem was the same as mine? Murph, you had any trouble starting the 2.6 now its cold again?

Worth changing the lambda?

[melinx]

When the engine is cold, there is no output from the Lambda sensor and the ECU software ignores it until the CTS says that the engine is warm. (in fact, the ECU 'forces' a voltage equivalent to stoichiometric onto the sensor until the engine is warm)

I'm not quite sure that I understand your linking a possible AFM problem with the Lambda sensor ??

[Murph]

Interesting. I had an undefined starting problem when it got cold last winter. When it warmed up it started. Murph later had the car and had starting problems in the summer which turned out to be the Lambda sensor. My problem starting could also have been a lambda problem when it was cold?

I wonder if your problem was the same as mine? Murph, you had any trouble starting the 2.6 now its cold again?

Worth changing the lambda?

I've had no problems since changing the Lambda, but the original problem was the fuel return valve on the fuel rail.

[man of kent]

When the engine is cold, there is no output from the Lambda sensor and the ECU software ignores it until the CTS says that the engine is warm. (in fact, the ECU 'forces' a voltage equivalent to stoichiometric onto the sensor until the engine is warm)

I'm not quite sure that I understand your linking a possible AFM problem with the Lambda sensor ??

No link, just suggesting  alternative problem solutions that Murph and I had on the 2.6. AFM and Lambda are both related to the fuel mixture control. The ECU gets messages from both I would have thought.

[PeterC]

That tell tale green/red ball thingy that tells you if the battery is OK. I have often wondered since I was told its a kind of hygrometer. I am not sure how it works but I think it probably only refers to the ONE cell it is floating in. So if any of the other cells are knackered you wont be able to tell. Please update me if I am wrong about that.

My feeling with cold weather is that it and condensation defeat poor connections. As time goes by these poor connections get bad enough that even warmer and warmer weather is not enough. I always think batteries give up in winter as well but I did coax one throgh a summer just to be defeated at the first sign of winter. All a bit of a generalisation but what I am saying is winter only finds/exacerbates what was going wrong anyway.

[melinx]

Your assumption is correct

http://autos.yahoo.com/maintain/repairqa/battery_electrical/ques027_3.html

Plus a very cold battery is not a happy one

[man of kent]

The only way to test a battery especially the sealed ones is a battery tester that puts a load across the terminals. If the voltage under load does not stay high it is dying. Whilst doing this it discharges by generating heat and in a good battery the coil will glow red yet the voltage stays high. its a good ivestment to buy one and you can use it for many years.

The problem with the little bright green balls in the battery is that it tells you the state of the charge is ok, but not the condition. You can have a battery that is only 10% efficient but if fully charged will show green. If it goes flat after a week then the chances are its on its way out. Hydrometers again tell you the state of charge but not the condition or life of the battery.

The bigger the battery, the better the chance of starting and the longer it will last.

[melinx]

Wot he /\ /\ /\ /\ says 

With a proviso that they seem to have some hand held computerised battery check instruments now that give the same (and more) information without having to stab the battery terminals and hope that you don't get molten lead flying round   

[melinx]

Over the past week or so during very cold temperatures, even with the new maximum sized battery, there have been some very difficult starts

A few degrees above zero, first touch it's away: Zero and below, lots of spinning

Although I have checked, cleaned and WD40'd them fairly regularly, I gave all the engine harness plugs another go and found that there was a noticeable improvement

I began to suspect the AFM internal connections were a bit 'iffy' when it got cold so I swapped it for my spare, the result was that it went first touch even below zero !!

Unsealing and removing the cover on the original AFM, I checked the spring connections that I mention in the photograph in the link below.

http://totalcarlton.com/forums/index.php/topic,13208.msg109123.html#msg109123

Checking them with a meter showed that they were marginally less than perfect but using a very small screwdriver and moving them about a millimetre each side of their rest position restored the connection to zero Ohms maybe they were considerably more dodgy in below zero temperatures

I haven't replaced it, I've left the spare on !

An update on this :- Last night I replaced the original AFM (now with cleaned connectors and potentiometer track) and left it to freeze overnight.

This morning it was minus 8 degrees outside and minus 2.5 in the garage: It fired up with no problems at all so I'm satisfied that it was the AFM causing the problem !