Audi A4 Cab 2.5TDI V6 Hard starting, loud engine and EML lights

[Sayedul Uddin]

Hi all, recently bought an Audi A4 Cab, had a 219 relay replaced a few days ago because of cutting out issues and all seemed to have fixed. Then today morning when I started the car, it started vibrating very loud, had a rough idle and the EML and ESP lights were on the dash. As I accelerated, the car seemed to be alot slower and was making really loud noises despite the revs being below 2000rpm. When I switched the car off couple of minutes later and tried it again, it wouldn't start! if i leave it for half an hour or so the car will start but will still give the same problems. I did notice while driving that the temp gauge went up to 90 very quickly. The car doesn't cut out or anything but feels like its about to fall apart. Full service was done 3 weeks ago.

Don't know what it can be, any help would be appreciated.

 

[abyrne153]

Any fault codes ? Could be any number of things but the injector pumps on these are common failures.

 

[Sayedul Uddin]

Will get it plugged into vagcom by tomorrow and update you, just to note I changed the 219 relay as the engine kept cutting out, this powers the injector pump. But the relay change fixed the problem i was rying to fix now this is a new problem altogether.

Car was driving sweet with no loss of power, very quiet up until today morning. I was thinking it could be a coolant temp sensor as it starts easier when engine is cold but still giving same issues regardless of hot/cold temp.

Sounds like a tractor!!

 

[abyrne153]

You really need to get the fault codes read. It could be any number of things but the injector pumps can fail like the flick of a switch so no matter how sweet it appeared to run before, it could fail without warning. Fault codes will hopefully direct you to the problem. Bear in mind though that A series engines do not throw up fault codes for problems with the EGR valve. Stuck egr valves can cause rough running and poor starting too.

 

[Sayedul Uddin]

Just had it plugged into to a diagnostic and there are 2 faults coming up...timing belt cant give a value ie. There is a malfunction in the timing and the other fault is the injector with needle lift sensor is faulty. Due to the way the car is driving and the fact that barely has any power and there is a loud rattle, my hunch is to just go straight to the injector but not 100%

 

[Sayedul Uddin]

The garage did have a look and couldnt see any wires connected to any of the injectors so couldnt distinguish which injector was carrying the needle lift sensor.

 

[abyrne153]

If you are standing in front of the car looking into the engine bay the needle lift sensor is on the injector nearest the back of the engine on the left hand side. The wire runs under the rocker cover so is not clearly visible. There is a DIY guide on this forum which gives the injector removal procedure and you can see the black wire in the pictures on there. You can test the sensor by attaching a multimeter across the terminals which should give a resistance of 100 ohms or thereabouts. There are specific part numbers on the injectors so make sure you get the right one if it shows up faulty. The pump ecu gets information from the needle lift sensor so the pump timing is likely being affected by this fault.

 

[Sayedul Uddin]

Thanks for the heads up, someone else has also suggested dealing with the injector issue 1st and see what happens from there, is that then the most sensible thing to do? Also my engine is the 163bhp BDG engine which is what the garage said. How can i check to see if theres more than one faulty injector? As the rattling is super loud and a friend thinks theres at least 2 or 3 damaged injectors.

Bear in mind i changed the 219 relay last week which powers the ECU, fuel pump and throttle valve. Starting to think it had a knock on effect...

 

[abyrne153]

Test the needle lift sensor first and if it's showing faulty then change it. It's part of the injector so if it's faulty then the whole injector needs to be changed. Eliminate the thing that is indicating a fault first.

 

[Sayedul Uddin]

Test the needle lift sensor first and if it's showing faulty then change it. It's part of the injector so if it's faulty then the whole injector needs to be changed. Eliminate the thing that is indicating a fault first.

Hi, didn't have a chance to test the injector as it didn't cross my mind when I popped into the garage, they did replace all 3 injectors on the left bank (including needle lift sensor) with second hand ones which I bought but the car is not starting at all anymore! Mechanic said he would charge the battery and try and get rid of trapped air and see if this changes anything, any other suggestions as to what can prevent the car from starting?

 

[abyrne153]

Probably just needs bled. Once it starts get the fault codes read again and see if your running issues Improve. You will likely need to slacken some of the injector nuts a bit whilst cranking the engine to bleed them through.

 

[Sayedul Uddin]

Probably just needs bled. Once it starts get the fault codes read again and see if your running issues Improve. You will likely need to slacken some of the injector nuts a bit whilst cranking the engine to bleed them through.

Garage have already tried to bleed it yesterday to no avail. They seem to think the replacement injectors are seized up but that surely would not stop the car from starting would it? Have asked them to re bleed the car which they will today but is there anything else that can be done? Garage have also suggested doing the timing on the car...

 

[S4_dan]

Pump timing would need to setup correctly via VCDS rather than tippex marks of the old timing setup. Make sure that if they do the timing they use VCDS.

Was the injector part numbers EXACTLY the same to those you removed from the car?

Also, vcds might show the injector quantity whilst cranking, worth a look.

 

[abyrne153]

Definitely check those part numbers as there are a few different types of injectors for these and they would need to be the correct type. Why did they change all 3 if the car was running previously ? Surely it was better to change the one throwing up the fault (the needle lift injector) and then try and eliminate any other afterwards. They can only check the static timing if the car isn't starting as they need to be running to set the pump timing correctly.

 

[Sayedul Uddin]

Hi guys, car has managed to start today after re bleeding but is throwing up the same symptoms as when the car went into the garage. EML and ESP lights on dash and car rattling loud. Garage did another diagnostic and now the needle lift sensor fault is gone so i think this has been rectified. The only fault showing now is the pump timing but do you think this would cause a loss of power and loud rattling? It is hard starting which is expected. Garage are using an autologic diagnostic which is supposed to be the dogs ******** lol

 

[abyrne153]

Ok so at least the fault code has gone. Pump timing can be checked with a full version of vcds with the engine hot. Is yours an A series or B series engine? The first letter of the engine code is the indicator. If it is an A series then the egr valve could be jammed open which can cause running issues but does not show a fault code. It may be that the diesel pump ecu is beginning to fail. I have seen this before where they cause running and starting issues but don't throw fault codes until they fail completely. Adamss24 is on this forum and if anyone can diagnose your problem he can. He's in London so if you are anywhere near there he's your man.

 

[Sayedul Uddin]

Its a BDG engine and garage have said the autologic diagnostic system should find any existing faults as its a 15k machine...i did change the 219 relay a couple of days before this issue started and this relay powers the injection pump as well as the main ecu and a few other vital components. Dont know if this triggered something...

 

[adamss24]

The B** series engines have hollow cams, i have rebuilt a few with cam issues. I would get the timing dialed in first, if you feel confident take it for a trip to London, i could look at it !

 

[Sayedul Uddin]

Im still waiting for the garage to correct the injection pump timing and hope this will cure the fault. After the advice from Chris regarding the 219 relay he became a legend in my eyes! I am in Birmingham and it would be too costly to have the car brought down to london otherwise it would have been in your workshop by now!

 

[adamss24]

Keep us updated... As i said in our previous chats, it's difficult to troubleshoot a car remotely ! Good luck with it...

 

[Sayedul Uddin]

Garage have played about with the timing and although the engine is sounding better there is still a loss of power and they believe it to be the injection pump! But there is no fault coming up? They will continue to adjust but will give up soon if nothing can be done.

 

[abyrne153]

I would be fearful the pump is failing but they do generally throw fault codes when they cause running issues. If you can get it to run at all then try your best to get it to Chris Adams. There are very few people that have the knowledge that he does.