VW CADDY TDI PROBLEM

2pack

I got 2003 caddy tdi van with E/M light on then goes into limp mode,
The computer shows up acceleration sensor but have fitted 2 and still the same.
I'm told now it could be the ECU but impossible to get a good one second hand as most at scrapyard are lying up and have took dampness in and are done and they cost a fortune new.
Any other solutions to this.

Thanks

101sean

Moved from 4x4, tractors, diggers and plant, more likely to get an answer here.

Andrew33

And if you switch off ignition and then back on again, does it drive normally again?
Does it go into limp mode when you floor it for a while under load? if it does, could be a problem with your vacuum hoses running to the turbo. Have you had the fault codes read? More info posted here will get you the answers, a common engine, a few well known and usually easily fixed probs.
Post up the actual fault codes if you have them.

couldntthink

Unplug the accelerator pedal. Get a pointy instrument like a needle or a small pointed screwdriver. Try and squeeze the connectors in the plug together. They don't need much squeezing, just a little bit. The contacts can be loose in the plug.

I've seen this issue a few times. Try that before you go buying anymore parts.

swhyte027

couldntthink wrote: »

Unplug the accelerator pedal. Get a pointy instrument like a needle or a small pointed screwdriver. Try and squeeze the connectors in the plug together. They don't need much squeezing, just a little bit. The contacts can be loose in the plug.

I've seen this issue a few times. Try that before you go buying anymore parts.

+1 on this

It's not a ecu anyway il bet that.even if u do get a ecu it won't work straight away as things have to be coded together and matched up.its not just plug and play so save your money

Chimaera

Limp mode on these is usually related to a boost control problem. Possible culprits are the boost control system: vacuum hoses rot and leak; N75 solenoid fails; MAP sensor dies; turbo control vanes soot up; VNT linkage rusts and seizes or breaks. All of those are far more likely than a faulty accelerator sensor or dead ECU.

2pack

From i start the van from cold i can usually go 15 minutes before the dreaded light Comes on and goes into limp mode, i lose throttle completely.
I did erase the fault immediately with scanner but could only goes minute or so before it was on again.


Ok quite a few faults have come up
Here they are

1.

18047
Accelerator position sensor 1 2 G79 G185
Implausible signal P1639

2.

17571
Fuel temp sensor G81 opel or short to plus P1163

3

00741
Brake pedal monitoring static-implausible signal

4

18025
Glow plug pre heat indicator K29 open or short to ground P1617

2pack

I have managed to clear the faults 2,3 and 4 for now but cannot get rid of 1 (18047)
just keeps coming back

couldntthink

2pack wrote: »

I have managed to clear the faults 2,3 and 4 for now but cannot get rid of 1 (18047)
just keeps coming back

Did you choose to ignore what I said? Not much point trying to help someone who won't listen.:rolleyes:

2pack

I did listen and did try that tip you give me before i posted again on here but i'm afraid it did not work this time for me.
I appreciate all advice..thanks

couldntthink

Fair enough

crosshair1

The Ecu would be high up the list of culprits on this van,
You could check the multiplugs into the ecu and open the ecu and inspect for water damage.
Also a golf tdi ecu would run this van like mk4 agr engine and these dont suffer from the water ingress problem

George Dalton

As above, open up the ECU and look for water damage. If it isn't the pedal or pedal plug contacts it will most likely be the ECU itself.

2pack

crosshair1 wrote: »

The Ecu would be high up the list of culprits on this van,
You could check the multiplugs into the ecu and open the ecu and inspect for water damage.
Also a golf tdi ecu would run this van like mk4 agr engine and these dont suffer from the water ingress problem

YOU mention that a golf mk4 ecu would RUN in this van too, but i would need one out of a 90bhp model and would i have to match the codes up too.. Can you elaborate PLEASE?????

I took the box out and there fair amount of corrosion on the outside of it but the board itself seems ok.
my ecu code is 038 906 018 FK. engine code ALH

crosshair1

Yes, I keep an ecu on the shelf from a golf tdi agr engine solely for getting these up and going and confirming a faulty ecu , I have used it with success on both sdi and tdi caddy/incas
ATM its fitted to an sdi until I can get time to fit the correct ecu so I cant get you the code until later this week.
The only issue with this is that unlike fitting key/immobox and ecu together, you will have to have the pin read from your immo and the replacement ecu adapted to it (the golf has immo in the dash not in a separate controller)

2pack

ok so does it matter if its out of a 90bhp or not as long as its engine code agr.

you say you keep one spare to get these up and running but if i fit one of these agr ecu unit in my van will not start until i code it in, yours must be decoded?

crosshair1

All i can tell you is the agr one will work they are all 90bhp, that is a very common engine in the mk4.
I am able to extract the immo pin for each van, so i can then match the agr ecu to it.

2pack

Thanks i saw 2 mk4 at local breakers so i may be lucky ..
what device do you use to code these in if you dont mind me asking?

crosshair1

The interface i use to extract the pin is autologic.
There isnt any point checking ebay for one:D

George Dalton

crosshair1 wrote: »

The interface i use to extract the pin is autologic.
There isnt any point checking ebay for one:D

Is that you Ray?

Are you sure an AGR ECU will work in an ALH? Are they not slightly different because the ALH has a VNT turbo?

crosshair1

Yep is indeed
the agr will definitely run the tdi, think the ahl is the only code fitted
will be some codes stored but runs without gplug light same with sdi

2pack

ok if i do manage to get one of these ECU's then and plug into my tdi van it will not start it anyway it until i get it coded it.. maybe vag com or ross tech can do this coding

2pack

Ok anyone know if this will work..

If I were to get a AGR ECU ( or a tdi van ecu with different part number to my own) from local breakers yard and plug it into my own van.
I then get a VAG device to remove or turn off the immobiliser from the AGR ECU.
I think my van would start and run ok or am I wrong.

crosshair1

"If" it is the ecu at fault... and as the board is clean there is a possibility the fault lies elsewhere.
If you dont have any equipment you have no choice but to look for the full key/immo/ecu kit from a tdi caddy.

2pack

hi, was also told that it can be 2 possible things with an ecu first one be dampness due to its location and second if a fault occured it can be stored deep in the ecu and thus cannot be fixed as will reappear so meaning ecu cant be fixed.

Chimaera

AGR may or may not work. Best bet is to get the ALH one - there's lots of those around so it shouldn't be difficult. You might get away without matching - even if the immo stuff isn't sorted out, it should at least start the engine briefly.