Starting problems.

[Gruff Mugen]

Hi folks. New to this so please bare with me thanks.

I recently bought my Audi a4 b7 sline 2007. 2.0lt tdi.

Only over the past few days Its started to give me bother. I'll try and explain in the best detail I can.

Normally when I put the keys in and turn to get reds it's would normally bring up the coil light and I would hear the pump prime and then coil light would go out and I could start the car.

But the odd time now I turn the keys to get the Reds and no coil light comes on nor do I hear the pump prime. Also the esp and abs lights stay lit. The car will crank fine but won't start. It does this now and again and I take the keys out of the ignition and then put them back in and try the same steps but still no coil light or prime sound. I'd try the same steps of removing the keys and inserting them again and after about five or six time of doing this I might be lucky and the coil light would come on and then drop out as it should and the pump prime noise is heard and I can start the car fine and drive away at it without any problems. I can then stop the car and start it again with no problems what so ever and I can do this for a few days and still have no problems. Then out of the blue when I go to start the car the same problem occurs- no coil light or prime noise, esp and abs light stay light. When plugged into the vag diagisnostics it's brings up engine control module intermittent/open circuit.

Can any one help.

Many thanks.

 

[Gruff Mugen]

sorry it come up with the following.

Instruments
01314- engine control module
004- no signal/communication - intermittent

Airbags
01221-crash sensor side airbag driver side
011-open circuit-intermittent freeze frame

Abs brakes
01314- engine control module
004- no signal/communication- intermittent freeze frame


There isn't any abs or airbag warning lights come up on the dash when the car is fine and not experencing the problem starting or when car is running normally.

 

[kev1973]

Sorry I cant offer any advice, I am having the same problem. I haven't noticed whether the fuel pump primes though. I have come across an old thread on here to which I have replied. If you haven't read it, It suggests it may be the ecu relay.

 

[Gruff Mugen]

Sorry I cant offer any advice, I am having the same problem. I haven't noticed whether the fuel pump primes though. I have come across an old thread on here to which I have replied. If you haven't read it, It suggests it may be the ecu relay.

Hi thanks for the reply. It's a blinking nuisance so it is. It always happens when I'm in a rush or have some where to be. I was thinking a relay but as im new to German cars I wouldn't have a clue where to even start looking or testing the relays. I think I'm going to end up having to leave it into an Audi dealer and grin and bear the bill at the end of it. (Yet again)

Thanks again for reply.

 

[kev1973]

agreed, mine has always done it in the morning on the way to work, luckily the last few times have been when the missus has been off work.
I don't think the relays are expensive, im going to just swap mine unless I get any further advice.

Im not a mechanic but I think its an easy swap, I think its just located near the ecu in the engine bay... google it for pictures.

next time it does it though im going to try tapping the ecu box.. to see if that starts it.

 

[Gruff Mugen]

agreed, mine has always done it in the morning on the way to work, luckily the last few times have been when the missus has been off work.
I don't think the relays are expensive, im going to just swap mine unless I get any further advice.

Im not a mechanic but I think its an easy swap, I think its just located near the ecu in the engine bay... google it for pictures.

next time it does it though im going to try tapping the ecu box.. to see if that starts it.

I've just spoke in person to an auto spark, he said that looking what the diagisnostics has brought up in reference to (engine control module no signal/intermittent) it means that on certain attempts to start car the (brain ecu ecm) isn't getting the signal to turn on/activate and that this is more than likely due to the relay for the ecm/brain/ecu. He said that these tend to get moisture from time to time. I'm booked in with him on Monday coming, I will update this as I get the information.

Any other advice or help from anyone with knowledge of this problem would be doing me a favour if they could help advise. Many thanks.

 

[kev1973]

ive just ordered the ecu relay,it was 15 pounds, its being delivered tomorrow. i tried to start it tonight and it wouldn't, so i tapped the ecu cover a few times and it fired up straight away. Worth a try to get yours going until you can try a new relay.

 

[Gruff Mugen]

ive just ordered the ecu relay,it was 15 pounds, its being delivered tomorrow. i tried to start it tonight and it wouldn't, so i tapped the ecu cover a few times and it fired up straight away. Worth a try to get yours going until you can try a new relay.

Great news, where did your order it from. Mines only after doing it again now after sitting all day, really doing my head in, got it started eventuly, Did you remove the black cover with the 6 spline screws or did you just tap on the cover

 

[kev1973]

Hi,

Sorry for the late reply, I've got a friend who's got a garage, he got it for me from a main dealer, it's a revised part so has a different number from the one mentioned in the thread. I haven't got round to fitting it yet. I just tapped the black cover of the ecu. Might just have got lucky doing it

 

[Gruff Mugen]

Hi,

Sorry for the late reply, I've got a friend who's got a garage, he got it for me from a main dealer, it's a revised part so has a different number from the one mentioned in the thread. I haven't got round to fitting it yet. I just tapped the black cover of the ecu. Might just have got lucky doing it

Hi, right enough I done the exact same on mine over the weekend and it worked. Car played about starting so taped the black box and the on comes the glow plug light and the pump primed. Done this a few times through out the day. Do you happen to know the number on the top of the relay by any chance.

 

[kev1973]

The relay is 614, the new one I have has got a different number due to the old one having a design fault (as mentioned in the other thread). Im sure if you call audi and ask for an ecu/614 relay they will know which one you need.

 

[Gruff Mugen]

The relay is 614, the new one I have has got a different number due to the old one having a design fault (as mentioned in the other thread). Im sure if you call audi and ask for an ecu/614 relay they will know which one you need.

Happy days least your on the track to getting the problem fixed. I Rang Audi today and they told me that my Audi has a 457 relay that is for the ecm/glow plugs/coil light. What year is your Audi and and spec ? Mines an 2007 Audi A4 sline black edition 140 bhp 6 speed. That's maybe why our numbers are different on the relays if your car is different from mine. I got the relay that I needed today from Tps (trade part Specialiest) so I'm going to put it in tonight and hope this is what the problem was all along. Ended up having to pay £76.64 for the relay . But if it fixes it I'll be happy at that lol.

 

[kev1973]

Mine is a 56 2007 140bhp s-line, the relay I have is a 644, I'm not sure about any differences in the engine, I would have thought they are the same.
Did you manage to fit it? I've not done mine yet, I finish work early tomorrow so will do it then, I'll update the thread.

 

[Gruff Mugen]

Mine is a 56 2007 140bhp s-line, the relay I have is a 644, I'm not sure about any differences in the engine, I would have thought they are the same.
Did you manage to fit it? I've not done mine yet, I finish work early tomorrow so will do it then, I'll update the thread.

Hello again, I fitted my relay a few days ago, all seams good, just check you have the correct relay mate. There are three relays in under the brain. I got mine from and vag trade place and that's the correct relay I put in mine. I tricked audi into giving me the part number of the relay and I went else were and got it a bit cheeper. Tho as I said all seams good atm with the new relay, Havnt experienced the problem since I replaced it. Hope yours goes just a smooth. Await your update bud.

 

[8BallAddict]

I'm having a very similar issue with my 2008 SLine A4 Avant 2.0 TDI. Only seems to be an issue when it's hot, or just after its been driven. When it won't start, the coil light does not light up. Leave it and 5 mins later and it is normally fine. Difference is I've got no fault codes on VCDS. I've had the coolant temp sensor and high pressure fuel pump changed and still got the issue. Definitely no sign of water damage in the ECU box, looks brand new in there. How have you guys got on with changing the relay's? I'm lost as what to do now!

 

[Gruff Mugen]

I'm having a very similar issue with my 2008 SLine A4 Avant 2.0 TDI. Only seems to be an issue when it's hot, or just after its been driven. When it won't start, the coil light does not light up. Leave it and 5 mins later and it is normally fine. Difference is I've got no fault codes on VCDS. I've had the coolant temp sensor and high pressure fuel pump changed and still got the issue. Definitely no sign of water damage in the ECU box, looks brand new in there. How have you guys got on with changing the relay's? I'm lost as what to do now!

Hi mate. I changed my relay and its seams to have fixed the problem. It should be located under the brain. I was getting the problem continuously and since changing the relay I've yet to experience the problem again (touch wood)

 

[kev1973]

Good stuff... ive swapped my relay now, seems to be ok but its not been done long enough to be totally sure, I saw the relay you swapped right next to the one I did, so If my problem reappears, Ill swap that one too.

 

[Gruff Mugen]

Good stuff... ive swapped my relay now, seems to be ok but its not been done long enough to be totally sure, I saw the relay you swapped right next to the one I did, so If my problem reappears, Ill swap that one too.

It seams me swapping the relay was to good to be true. Only last night have I just started experiencing the same problem yet again. I can't get my head round this at all. I wonder what the other two relays under the brain are for, one of these must be the problem as I've changed the third one that I assumed was faulty that works the pump prime and glow light and heater plugs. Really pi**ing me off now.

 

[kev1973]

That's a bummer, you could try the 644 relay, that I swapped, my friend asked audi for the ecu one, mine hasn't done it since, but it's still too early to say it's cured.. I'd try it, as it's not as expensive as the one you swapped.

Good luck, I'll keep an eye on this thread

 

[Gruff Mugen]

That's a bummer, you could try the 644 relay, that I swapped, my friend asked audi for the ecu one, mine hasn't done it since, but it's still too early to say it's cured.. I'd try it, as it's not as expensive as the one you swapped.

Good luck, I'll keep an eye on this thread

I know it's a bummer indeed. Can you remember outta the three which one is the ecu mate

 

[kev1973]

I know it's a bummer indeed. Can you remember outta the three which one is the ecu mate

Yeh, it's the 614 relay which has been changed to a 644 due to a fault.

 

[Gruff Mugen]

Awesom

Yeh, it's the 614 relay which has been changed to a 644 due to a fault.

Awesome mate that matches mine, there is apparently two of these under the brain according to Audi. The info for this relay is (closed circuit relay) 614 changed to a 644 as you've said. Thanks bro I'll give these two a blast and keep you updated. Thanks again for the help

 

[kev1973]

Awesom


Awesome mate that matches mine, there is apparently two of these under the brain according to Audi. The info for this relay is (closed circuit relay) 614 changed to a 644 as you've said. Thanks bro I'll give these two a blast and keep you updated. Thanks again for the help

Nope, only one 614 relay, well only one I saw! There are three relays under the ecu, a 614, the one you changed earlier and another one. Which I can't remember it's number but it's totally different

 

[Gruff Mugen]

Nope, only one 614 relay, well only one I saw! There are three relays under the ecu, a 614, the one you changed earlier and another one. Which I can't remember it's number but it's totally different

See I thought that two. I only saw three. The one I changed is the coil light and glow plugs, the one you changed is the closed circuit relay and the third one is for the fuel pump according the audi. I may as well change the remaining two lol. Course I changed the dearest one first at 79 quid. The other two are 16 quid each. Not a happy bunny if I'm honest considering the replacement I done hasn't even fixed the problem lol may as well trough 80 quid outta the car window. Ordered today the one that you changed so all being well this sorts the problem. Fingers crossed you got the problem fixed first time round.

 

[kev1973]

Just an update, my car appears to be sorted, not had any problems since.

 

[Green Beans]

Hey Guys,

Just bought a 2012 Audi a3 sline last month and have dropped nearly 3500 in parts so far on it with coilovers and such the build has begun but I have a **** load of codes that point to the ECU .... I hope you may have solved my issues. This is located under the wipers on an A3 correct ? First thing I am checking in the morning as I tear the intake off and see WTF is stuck open lol...I am old VW fart mechanic that is upgrading to one in fancy dress but apparently this ones like a girl friend multiple personalities ...oh and a new clutch going in next weekend...oh joy ! just waiting on parts and shipping sucks....thanks all appreciate the info and community

 

[tr7]

Any idea what and where these relays are @kev1973 is talking about?

I'm having similar issue and have another car so would like to swap over relays and see it it makes a difference

 

[butty23]

Hello all, I thought I’d post my experience with this issue too. Quick background… had an intermittent starting issue with an a4 cabriolet 2009 tdi s line, which various garages and rac guys looked into without success. Car would sometimes go into limp mode too, but on the whole tan like a dream. When turning key in ignition before start up I would get a light level fault and alarm which would clear however car would crank but not start. To get over this I would disconnect battery on both terminals to drain down relays for 5 minutes and re connect. This normally sorted issue until yesterday when I had to leave overnight when it did start. Having read thread I have just now replaced relay 614 with another for £5! . This was located on the drivers side under bonnet, remove 5 screws (2 of which I bastardised)! Of black cover, remove long clip and 2 relays are underneath the ecu.
I hope this helps someone, I’ve spent over a year trying to sort and will see how this goes. If anyone has further knowledge of this I’d be keen to hear.