1.9 Tdi PD issues, can anybody help?

[I_am_Diesel]

Hi guys,

 

Yeah, I know it's VAG and I should know better but.....

 

My Caddy is suffering from epic FTP.

 

It all started over a month ago when I trusted one of the workshop monkeys to re-gas my air con. He did all the good stuff with the machine but it still wasn't blowing cold so he decided to pull fuses and mess about with the electrics, possibly whilst the ignition was still on.

 

Driving home that night, it hesitated a couple of times and after 8.5 miles it stopped and wouldn't start. The RAC chap got it going again with Easy Start and followed me back to work where I had another FTP so more canned repair was needed.

 

VCDS didn't show any codes, it seemed like a fuel starvation issue so I ordered a priming pump off t'net which took 2 weeks because it came from Germany. Fitting the pump was a pain because I had to drop the tank and hey presto!, it broke down again.

 

The fuel filter housing was empty, pump was pumping for a couple of seconds when I switched the key on so I suspected the pressure valve at the top of the fuel filter housing. I procured a second hand item off a popular internet auction site, fitted it and again experienced a FTP.

 

Pissed off, I took the ECU out and sent it off to be tested/repaired, hoping that was the issue. It wasn't, after over £200 spent I haven't made an iota of progress.

 

I suppose the purpose of this topic is-

 

a. To ask any advice if anybody can help please?

 

b. Vent my spleen!!

 

As soon as I can get this sorted, I'm selling it and I don't give a monkeys chuff if some bearded beanie wearing bozo buys it and pineapples the fucker.

 

I feel better already.

[twosmoke300]

Initial thought was the fuse to the low pressure pump in the tank . Fuck the primer pump off as the one way valve may be causing more issues .

They will run without the tank pump but a twat to start .

Pull the in pipe off the filter and route into a jug . Ign on and should pump fuel for about 3 secs

[twosmoke300]

Ahh by priming pump do you mean the one in the tank not a squeezy one?

[twosmoke300]

Oh and make sure the filter pipes are all in the right places . Easy to muddle up

[I_am_Diesel]

It does that, I have had the pipe off and fuel does piss out for about 3 seconds.

 

The tank pump doesn't seem to be doing a lot when the van is running. We had the top of the filter housing off while it was running to see how much fuel was getting to the filter and it just kept going with a few drops dripping out into the outside of the fuel filter housing. I thought it would have died straight away when we did that.

[I_am_Diesel]

Pipes should be right, I double checked.

[twosmoke300]

There's a relay ( 109 possibility) that switches from initial ign feed for the pump to an ecu switched feed when it's running

[I_am_Diesel]

That could be something worthy of investigation. Thank you for the sound advice.

[twosmoke300]

As I said they will run without the leccy pump but only when plenty of fuel . The tandem pump on the head will suck it up from the tank to a point .

[I_am_Diesel]

It just seems too much of a coincidence that all this came about when the electrics were messed about with. I had it ticking over for 50 minutes today. I stopped it, left it for a bit, started it again and at some point it stopped again.

[cobblers]

Yeah I was gonna chime in with that "load reduction relay" I think they call it, if someone's been fannying about it could have ended up back in the wrong hole or halfway out or something. I've seen them in diagrams but never worked on one so I don't know how they'd behave with it missing.

[dieselnutjob]

relays are a common failure with VAG diesels.

When the relay fails the ECU has no power and so doesn't log any fault codes.

The original relays appear to be marginal and overheat or someit

[doug]

My 1.9 TDI polo used to cut out at random times. Italian tune up sorted it.

[I_am_Diesel]

Mine won't stay running long enough for an Italian tune up.

[doug]

Think the actual problem with mine was the EGR blocked up with crud. Might be the same with yours.*

 

 

 

 

 

*I am no mechanic though,hence the Italian tune up method used.

[Dave_Q]

Think these have got one of those shitty abominations attached to the battery box with a few maxi fuses etc?

 

Take it to bits and clean it up, have had mystery ftp/electrical gremlins on various cars because of those things.

 

Also, on a previous Fabia, there were assorted earth points under the battery tray that were well crusty, a clean up of those sorted some electrical shizz on that one.

[tommotech]

Have experienced similar problems with Caddy TDi, it was the relay mentioned above. Swapped and sorted.

 

Good luck!

[Ghosty]

At the moment, it Pumpe Düsen't.

 

Hope it Pumpe Düse again soon.