1.4 Tdi Struggling to start..
- Thread starter DaveySprocket
- Start date
depronman
A2OC Donor
I would not be to quick to rule out the new tandem pump being faulty (I think it was neither Bosch or LUK) and the old pump being worn
The answer on the fuel cooler is it was fitted to keep the fuel as cold as possible because cold fuel burns more efficiently
There may be side benefits as well but the efficiency is the main reason
Some 1.9pd engined cars had the cooler others didn’t but the ones that didn’t had large fuel tanks not the tiny 34L tank that the A2 was designed with. The larger the tank the more cooling effect there is from the mass of colder fuel in the tank
The ecu uses the fuel temp sensor to determine how much to adjust the fuel maps by. Warmer fuel = more fuel injected = less MPG
Paul
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DaveySprocket
A2OC Donor
To my knowledge these injectors have not been out at all, bear in mind the car has done 175,000 miles though!
At least one person on here has said that they had the exact same starting symptoms and it turned out to be the injector seals causing the problem, I will have to look back and try and see who it was..
depronman
A2OC Donor
I’m not filling out the injection seals but it is rear on the PD engines
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audifan
A2OC Donor
Still not convinced it is not a porous connection or clamp that is the issue. The pipes and all connections must be perfectly sealed. The tandem to head must be perfectly clean and flat. The tandem needs to be quality. If a tandem locating bolt has been over torqued this could cause enough distortion on the head to let air in.
PlasticMac
Admin Team
I know I'm just an observer here, but I can't see how the volume of air seen in the return, when running can to can, could come in via injector seals, especially with no evidence of diesel leaking out. How can air enter a high pressure fluid area, without a matching fluid leak?
Mac.
Mac.
DaveySprocket
A2OC Donor
It does seem curious to use a metal gasket in this application, and the bolt pattern, and 2 different sizes of bolt can't really help getting a good seal. At the same time there are a heck of a lot of VAG engines out there using this arrangement I guess 
I tried a different pump (LUK) because of the symptoms, and to see if the gasket was the issue, and there was been no improvement. Now it has the original pump back on with a new gasket (Elring gaskets btw) and no improvements either.
At the time I got the MOT, it was entirely driveable though, so I have to admit that somehow I have made things worse, which if course is not entirely the way forward
I tried a different pump (LUK) because of the symptoms, and to see if the gasket was the issue, and there was been no improvement. Now it has the original pump back on with a new gasket (Elring gaskets btw) and no improvements either.
At the time I got the MOT, it was entirely driveable though, so I have to admit that somehow I have made things worse, which if course is not entirely the way forward
DaveySprocket
A2OC Donor
I've been trying to find anyone who has mentioned injector seals as contributing to this issue..
A2Steve was one person that mentioned them as a possible cause, these are two others..
www.a2oc.net
www.a2oc.net
Nothing very definitive..
A2Steve was one person that mentioned them as a possible cause, these are two others..
1.4 Tdi Struggling to start..
I would suggest getting the car scanned with VCDS instead of your code reader. It might show up the fault in the form of a code that only VCDS can find.
www.a2oc.net
Poor starting
Hello all I have a 2001 1.4 Tdi which sometimes starts first turn and sometimes takes ages cranking the starter before the engine finaly comes into life. Having assumed that the problem was with the glow plugs, I ordered a new set from AVS Car parts and have just replaced the old ones with...
www.a2oc.net
Nothing very definitive..
DaveySprocket
A2OC Donor
Yes indeedy, have used two of these:
Elring OEM Fuel Vacuum Pump Gasket for Audi A3 A4 A6 Mk4 Mk5 VW Golf TDI | eBay
For Volkswagen Bora, Caddy, Eos, Mk4 Golf, Mk5 Golf, Golf Plus, Jetta, Lupo, New Beetle, Passat, Polo, Sharan & Touran. 1.4TDI, 1.9TDI and 2.0TDI Engines. A3 1.9TDI & 2.0TDI inc Hatchback, Sportback and Convertible 2001 on (ATD, ASZ, AXR, BKC, BMM, BLS, BXE engines).
www.ebay.co.uk
I've been trying to find anyone who has mentioned injector seals as contributing to this issue..
A2Steve was one person that mentioned them as a possible cause, these are two others..
1.4 Tdi Struggling to start..
I would suggest getting the car scanned with VCDS instead of your code reader. It might show up the fault in the form of a code that only VCDS can find.
Poor starting
Hello all I have a 2001 1.4 Tdi which sometimes starts first turn and sometimes takes ages cranking the starter before the engine finaly comes into life. Having assumed that the problem was with the glow plugs, I ordered a new set from AVS Car parts and have just replaced the old ones with...
Nothing very definitive..
@rkeil I believe also commented the same solution a few pages ago in this thread?
I fitted refurbished & tested injectors to my project car and it made a huge difference to the smoothness and economy of the car, as well as eliminating occasional revving on startup that was attributed to worn injectors leaving a bolus of fuel in a cylinder. It had already had a leaking fuel filter canister and tandem pump replacement by this stage.
DaveySprocket
A2OC Donor
I took a fully charged battery down to the car today, and got it started up after a good 40 seconds cranking. I should have just left it running, to try out JohnyFartboxes theory of bleeding the air out, but I couldn't resist blipping the throttle and it immediately stalled and wouldn't start again no matter what 
I'm just gonna leave it for now until my brother in law next pays us a visit, as I'm sure with his help I will be able to properly get to the bottom of what is going on.
I'm just gonna leave it for now until my brother in law next pays us a visit, as I'm sure with his help I will be able to properly get to the bottom of what is going on.
DaveySprocket
A2OC Donor
Hi Robin, did you sort the injectors with the engine in the car? I’m guessing it’s doable, but probably quite awkward?
The mechanic did. The cabin air intake trumpet is best taken off to give proper access over the top of the rocker cover (he was also replacing EGR and turbo at same time so it was all done in one go) - but both the fact the injectors had been renovated and tested, and he also reset the rockers according to the workshop manual meant it was running like a sewing machine afterwards.
DaveySprocket
A2OC Donor
Okay good to know, I will have a look and see how that trumpet comes off. Cheers
From memory it is easiest if you remove the rubber seal at the back of the engine bay and then release the plastic scuttle panel (does this require the wiper coming off?) - this then gives you access to two fixings that secure the trumpet to the area of bodyshell below the scuttle panel (open to correction!).Okay good to know, I will have a look and see how that trumpet comes off. Cheers
Here we go. From the first few pages of the workshop manual section on working on camshafts and injectors etc before removing the rocker cover : (bear in mind it is left hand drive so there is an intercooler return pipe and a couple of other things obviously in the wrong place for ours but concept is the same).
Once you get to removing the rocker cover there is a specific order and torque to remove (and ultimately refit) the rocker cover bolts to mitigate risk of warping - @audifan Graham has posted this info recently here in a different thread but should be easy to find.
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Edit.Hi Robin, did you sort the injectors with the engine in the car? I’m guessing it’s doable, but probably quite awkward?
One other thing I forgot.
Apart from the cabin air trumpet, I've got a vague recollection the mechanic also undid the engine mounts at (I think) the top of the engine and was able to swing the entire unit forwards a few degrees (inches in an otherwise confined area) that also gave vastly better access to the rear of the engine for the inlet / exhaust manifolds and EGR. However, don't quote me on this.
DaveySprocket
A2OC Donor
Wow, thanks for that!
johnyfartbox
A2OC Donor
Undoing the engine mounts is common practice with all work done at the rear of an engine, I believe it's also done when changing the water pump and cam belt.
Little Dog
A2OC Donor
I've done these jobs recently,
Yes to wipers, scuttle and trumpet (didn't know it was called that) off
Now the cam cover can be taken off but access to two screws at the rear is difficult.
Access to those two screws is easy if the EGR is removed. Contrary to popular belief an easy job if you remove the lifting eye on the back of the cylinder head first. Access the lifting eye from under the car.
Access to injectors is easy once the cover is off but you may need an injector puller to get them out.
Injector fitting is straight forward but you need large vernier calipers to position them correctly. Cooling pipes get in the way setting injectors position with the engine in the car. I also used a DTI to set the injector stroke but I understand this can be done by eye. Best Google to check.
Yes the OS engine mount comes out for a belt change.
No need to touch mounts for anything exhaust relate right back to the turbo. Only worked on turbo with the engine out of the car.
Yes to wipers, scuttle and trumpet (didn't know it was called that) off
Now the cam cover can be taken off but access to two screws at the rear is difficult.
Access to those two screws is easy if the EGR is removed. Contrary to popular belief an easy job if you remove the lifting eye on the back of the cylinder head first. Access the lifting eye from under the car.
Access to injectors is easy once the cover is off but you may need an injector puller to get them out.
Injector fitting is straight forward but you need large vernier calipers to position them correctly. Cooling pipes get in the way setting injectors position with the engine in the car. I also used a DTI to set the injector stroke but I understand this can be done by eye. Best Google to check.
Yes the OS engine mount comes out for a belt change.
No need to touch mounts for anything exhaust relate right back to the turbo. Only worked on turbo with the engine out of the car.