A4 1.9tdi avf hard starting

[Highlandreid]

Hi all. Recently bought an 04 1.9TDI AVF 130 and I have the following problem. When starting cold, its is hard to start (takes around 5 secs). At the same time I get the brake light flashing and 3 beeps from the dash as well as a bit of smoke out the exhaust. I've replaced all the filters and fitted a new battery. There's oil around the EGR, and the temp sensor was replaced by the dealer I bought it from to clear an Engine Management light. The beeps only seem to happen at the same time as the hard starting.

Can anyone advise what might be causing the beeps and hard starting? The liquid from the old fuel filter was clear yellowish in colour. I found out a few days ago it had a new camshaft, valves timing belt etc fitted by Arnold Clark earlier this year when the previous owner decided not to change the TB when the water pump was leaking...I've seen possible solutions on here that include EGR, tandem pump leak, air leak on fuel lines, incorrect timing or fuel timing, but not sure the best place to start...Any advice appreciated.

Dennis

[philfingers]

you've checked the glowplugs are working ok?
Timing may need looking at if it's just had a new cam fitted

[Highlandreid]

Hi Phil

Not checked the glowplugs yet...is this just a case of checking the resistance of each plug?

Cheers
Den

[philfingers]

remove the engine cover and down the RHS of the engine are the glow plugs. Pull the caps off and check the resistance. I would guess at 0.5 to 0.8ohms. If they're all ok, put the voltmeter in one of the glowplug connector wires and get someone to turn the engine on to the pre-ignition, where you would see the preheat light come on. The voltage should come up. if not it's a fuse issue maybe. Below about 5 to 8deg they stay on a fair bit longer.
Pays to check the obvious first. My old 2.5TDi was struggling to start and all the glow plugs had gone open circuit, replaced them all and it was fine, even at -15degC

[Highlandreid]

OK. Cheers Phil. I'll check it out tonight.

[nevo]

The brake alarm and bleeps are probably a low voltage spike caused by the excessive cranking.as above first things first glow plugs.

[benjie]

x3 for glow plugs - this has happened twice to me when the weather's turned cold (and the plugs are more important) and both times, 4 new plugs sorted it.

[Highlandreid]

Checked the front 3 plugs and all read a resistance of ~1-1.2 ohms which would seem to be OK. I'll have to check the last one at the weekend because the access is awkward esp. in the dark! I'll see if I can get a helper to check the wiring tomorrow...

[nevo]

Check there's voltage at the plugs,try taking one out,dont force it,its not worth risking it,if one comes out easily try it on the battery,degrease the threads and clean up the connections.

[Highlandreid]

Right been a bit busy lately and I've been waiting for some service history from Arnold Clark. All 4 plugs were replaced 2 months ago, the same time as the head was off valves camshaft cambelt etc replaced. According to the guy who did the job, the previous owner was complaining of rough starting before this so whilst the timing might be off as a result of the new recent head rebuilt this might not be the source of the problem. I haven't had a chance to check the voltage yet from the leads, but hopefully I'll get someone to help with this in the next few days. In the meantime bought a Genden dualK line cable and I'll do a fault code read to see if this throws anything up. The seals on the T-piece to the fuel filter were damaged and I've replaced these and I luckily picked up a cheap Pierburg EGR valve to replace my current unit which is leaking oil out the drain holes. I'll post how I get on hopefully this weekend. PS The hard starting is only when the car has been left for more than ~ 10 hours or so which makes me think its not the plugs...

[A4 Lad]

Leaking seals will do this everytime. Lets the diesel run back into the tank after sitting for a while


Sent from my iPhone using Tapatalk

[Highlandreid]

Which seals are we talking about? Injectors???

[sline002]

isn't a good idea to check it first with vag-com?or something similar before to buye anything you may not need.

[nevo]

He'll be taking about the o rings on the fuel filter t piece,dont think your timings out if it starts ok warm,try clamping the fuel feed between the filter and the tandem pump with a brake clamp,leave it overnight,remove then try a cold start,also check the operation of your lift pump,remove the feed hose at the filter,put a container at the end and give it a few turns of the key, ignition only.

[Highlandreid]

OK. I'll check it out. I replaced the O-rings on the T-piece already. Just to check if I clamp the fuel line to the tandem pump this prevents the fuel draining out the lines so that when I take it off and try it the morning, the idea is that it should start easier, correct?

If it does then this indicates a prob with the tandem pump?

I should be hopefully checking with VCDS tonight for any other probs in any case.

[nevo]

Thats correct,the seal inside the two sides can draw air from the vac side to the fuel slowly overnight,just a test to eliminate that,dont forget the lift pump test,you'll probably find no codes stored.Incidently are you getting any smoke out the back on problem starts?

[Highlandreid]

Occasionally yes. A bit smokey on start up for a few seconds.

[nevo]

You will get some smoke on a prolonged crank,I was refering to any clouds of white smoke,but I guess you would've said in your first post,anyway keep us posted.

[Highlandreid]

I've just clamped off the 2 fuel lines from the filter to the pump ~ 8" away (close as I could get without removing anything), so I'll see what happens tomorrow. The pump is a Bosch 038 145 209C.

Is a LUK 038 145 209N the correct replacement PN for this as I've seen a few relatively cheap ones lately...

Incidently the fuel lines to the pump have new hose clamps on them so I guess this was taken off when the head was removed.

[nevo]

Dont buy a new pump just yet, if it starts ok you need to check whether the non return valve in the pump return line is holding,just remove the pipe put a container under and switch on the ignition a few times to get the lift pump to operate,it shouldn't pass any fuel.

[Highlandreid]

Removed clamps after been standing for 12 hours and although I stilll got beeps it definately started a lot quicker than normal (although still not instant).

I'm not sure which fuel lines I need to unclip for the lift test. I originally though you meant to unclip one then turn ingnition so making sure the lift pump was pushing through a few cc's of fuel, but obviously this isn't right reading the last post. A few tips here would be very much appreciated...

One other thing which may or may not be relevant. When I first got the car, the oil level was too high (~5mm+). I assumed this was because it was overfilled, so I changed the oil and filters and have kept an eye on the level which hasn't changed as far as I can tell in the last 700 miles (the car is used pretty much every day).

[philfingers]

did you ever get to check the glow plugs? I can't imagine it's tropical in Scotland this morning!

[Highlandreid]

Mmmm think its a toasty 8 degrees today! Apart from the plug resistances and then subsequently finding out they were replaced 2000 miles ago no. I think the clamp test probably showed its fuel related though...

[nevo]

The return line out of the tandem pump(where the fuel line attaches)has a pressure check valve inside,basically a non return valve,with the feed attached and the return removed, switch the ignition on and off a few times and make sure no fuel passes out,it maintains the pressure in the rail.

[stu_m]

dont slate me for this as it may sound odd!!

try sticking your side lights on before starting!!!!


i have starting problems on mine it will turn over for about 5 seconds before firing but with the side lights on it will fire straight away

i have done a bit of looking about and found a few people with the same problem!!

it turned out to be a short in my headlight switch in the off position that causes the problem :confused:

you may aswell try it to rule it out

Stu

[Highlandreid]

I removed the return line at the filter t- piece and got the missus to switch the ignition on ~8 times. I had a very small amount of fuel come out maybe 1 or 2 droplets. Does this sound OK? If there's a chance the pump is defective I'd rather just change it than have any diesel in the engine...

[nevo]

that looks as like its holding ok,now get a strong light and check at the back and underneath the pump for any evidence of leakage down the back,bit cramped maybe use a small mirror.

[Highlandreid]

I tried that already, but the problem is there's a fair amount of oil around this area because of oil leaking out the EGR valve drain holes, so its difficult to say if anything around here is a fuel weep or the oil leaking from above....

[yaman]

Make sure all the fuel lines, up to and including the injectors, are
done-up nice and tight, but don't ring them.

Fuel joints can be drawing-in air without leaking fuel.

Regards
Jim

[nevo]

Another thing you can check,your anti shudder valve could be sticking on shut down,just check its operation and innards for gunk.

[nevo]

Try nipping up the pump bolts a little.

[busteroonie]

yeah we had start up troubles and found it was the headlamp switch, weird.

[Marco34]

My car is identical in this freezing weather. The engine is in super condition but my battery is original so 9 years old. I can wait 6-8 seconds at -6 for the glow plug light to go out. Cranking at worst can be 3-4 seconds. I've concluded it's the cold and an aging battery. No fault codes with VCDS. I have no gunk near EGR etc and fuel filter within 18 months old and 10k.

I get smoke too. Much more than normal but most diesels I see do.

Is yours ok after 10 seconds or so??

Cheers.

[karl_tanner]

This is great reading!
I gotta "R" reg 1.9Tdi A3, and lately it's a complete b**tard to start..
I found that the "glow plug" relay wasn't being energised.. Even though the light on the dash came on. This is controlled by the ECU, no way am I replacing that. So I made a little timer circuit which brings the glow plugs come on for 10secs when the ignition comes on.
However, it's still hard to start... I have seen some fluid on the fuel filter... So it's the o-rings in the connections that fail?

I'll check the glow plugs too, keep us posted if you find anything else!

Cheers

Karl :D

[basic147]

Dont buy a new pump just yet, if it starts ok you need to check whether the non return valve in the pump return line is holding,just remove the pipe put a container under and switch on the ignition a few times to get the lift pump to operate,it shouldn't pass any fuel.

Great thread I have a similar issue so im working through a few of these pointers. My audi won't start easily if its been parked on an incline so im pretty sure I have an issue thats being covered here.

Please can someone explain the above post again so I can understand thanks?

[Grangey.]

Guys sorry for the thread revival, but ive just baught a 1.9tdi 130 B6 with starting problems and thanks to someone pointing me the answer on another fourm- believe it or not the pointer on page 3 by stu_m is absolutley bang on. So i thought it also worth posting in this thread for other people searching for the fault.

This is not the answer to the thread in question (ie the starting on a hill etc) but if your a4 tdi130 takes some time to start (about 10 rotations or so)......

Believe it or not ITS THE HEADLIGHT SWITCH that causes this fault in most cases! Put your sidelights on, then turn the ingition, i bet it starts almost faultlessly. I've got a friend that works in audi that confirmed that there has been a run of these faults which have been related by the switch (ie the part you turn from O to sidelights to headlights)! Im not techincal enough to understand why, but it seems to fix it!

i thought i should put this in for others looking for this fault.

[Pentti]

Not sure about the 1.9TDi engine layout, but have had a similar fault with my 2.5TDi ie brake warning comes on and I have been told its the battery complaining, as suggested by Nevo. My problem was caused by leaking injector leak off pipes.

[funkyfin2000]

Did you ever get to the bottom of this! Would love to know! Sent you a PM!