406 diesel intermittent starting problems

loz · Post by **loz** » Fri Oct 27, 2006 4:36 pm

Hi, another newbie after some helpful advice!

got an s reg 1.9 td lx, 97, 000 on clock, recently serviced, about 6 months ago wouldnt start. called breakdown recovery , guy said the battery was goosed. got a new battery things were fine for a while, then she wouldnt start again. tried 5/6 times, , no joy, left her for about 30 minutes and then she fired up first time. mate reckoned it was glowplugs, got them checked and they were fine.apparently. was waiting for ignition coil indicator light to go out before turning over, mate suggested waiting for 30 secs after light went out beofre trying to start again. this seemed to work for a while - started 1st time everytime , so assumed it was just one of those things.

one morning went to go to work , would not start at all, even after leaving for 30 mins and re -trying. breakdown called again, guy removed hose and sprayed damp start all around engine bay, when turning over it just would not spark. then it sparked coughed into life and then died. guy asked me to remove immobiliser , told him i didnt have one - all i have is a key - no fob or anything like that - was bought second hand.

If it was a petrol car i would have worked through ignition system (used to have a mini) cos it seems like it is just dodgy plugs not firing however these have been tested by breakdown guy.

from reading through the forum i am unsure as to whether I should by an immobiliser fob of ebay and reset / change the glow plugs/ or is it a fuel pump issue.

after the last recovery bloke had a look he stated that the immobiliser needed resetting and said it would have to go into a pug dealer as they had the software to do this.

pug garage said the ECU was dead , needed replacing at £450 + £50 per hour labour. they phoned next day to advise they had replaced fuel relay switch and this had resolved the issue.

picked car up , wouldnt start, tried 3 times, went into garage kicking off, mechanic came out and she started first time. made me look a right numpty but said i still want happy

has happened about 6 times since, but have always managed to get her started.

When i was trying to start her one day i heard a little click from engine , turned it over and she fired into life. since then i listened for the click and she seems to work. only problem is when it is raining i cannot hear the click. there seems to be no pattern - hot / cold engine maked no difference, rain or dry, full tank, half empty tank.
can't afford the new ecu, don't mind spending a bit of money but don't want jsut replace parts on the off chance
main question really is is it the immobiliser / electrics / or failing fuel pump / glowplugs????
help as i have no faith in the car, which is a shame as she is the best one i have owned so far. but need a reliable car for work

btw once running drives like a dream

cheers in advance

Davva2004 · Post by **Davva2004** » Fri Oct 27, 2006 5:48 pm

Thing is, you already know what the problem is - the ECU has a fault and needs replacing. You can replace pretty much everything else under the bonnet if you wish, but if you don't change the ECU you're not going to be able to fix this fault.

loz · Post by **loz** » Fri Oct 27, 2006 6:26 pm

cheers davva, my ignorance is no excuse I agree, however I was told that the pug dealer was trying to fleece me as if the ECU wasn't working then the car would not work at all? Is this not the case then - as mentioned before my knowledge on 'newer' cars is non existent - all i needed on the mini was a 13mm spanner!

as I know little about ECUs if I was to buy one from a scrappy / ebay and swap over, will this rectify the issue, or just make it easier for a mechanic to diagnose the real problem - I saw an ECu on ebay for about £15 , which is slightly better than £450 quoted from pug garage. Another thing - is it not a simple matter of unplugging one ecu and putting in the new one? Why would they charge for up to 4 hours work, - are my local garage just trying to really rip me off?

cheers for the info!!

trem1 · Post by **trem1** » Fri Oct 27, 2006 6:34 pm

loz wrote:cheers davva, my ignorance is no excuse I agree, however I was told that the pug dealer was trying to fleece me as if the ECU wasn't working then the car would not work at all? Is this not the case then - as mentioned before my knowledge on 'newer' cars is non existent - all i needed on the mini was a 13mm spanner!

as I know little about ECUs if I was to buy one from a scrappy / ebay and swap over, will this rectify the issue, or just make it easier for a mechanic to diagnose the real problem - I saw an ECu on ebay for about £15 , which is slightly better than £450 quoted from pug garage. Another thing - is it not a simple matter of unplugging one ecu and putting in the new one? Why would they charge for up to 4 hours work, - are my local garage just trying to really rip me off?

cheers for the info!!

if i hover over ECU why does it describe it as electronic control united surely it should be unit

turbolag · Post by **turbolag** » Fri Oct 27, 2006 6:37 pm

loz wrote: are my local garage just trying to really rip me off?

Perhpas, but more likely they just don't want the job and have quoted you sufficient to scare you away!

ECUs, like you ma's old TV, can fail intermittently. Dry joints or cracked boards can make/break contacts seemingly at random, dependant on factors such as vibration, temperature etc. Your ma's old TV up the swanee again? - give it a smack and it might spring back into life. Same idea for ECUs.

Swapping one should work, but i'm not sure about how thigs such as keyless entry etc might be affected as i'm not so up on the ECUs on 406's. no doubt one of our illustrious brothers will be able to confirm the point.

Post by **Welly** » Fri Oct 27, 2006 7:37 pm

I know this is a different car, but have a read of this, the ending is quite unique and may help you.....

viewtopic.php?t=1536

Welts

Captain Jack · Post by **Captain Jack** » Fri Oct 27, 2006 11:08 pm

I am probably talking out of my arse here, but I thought that 1.9 TDs were completely mechanical...?