1.9tdi ALH starting issue

Hi, Ive spent a couple of days finding someone with a similar problem that I'm having, i tried Swedish sites first since I'm from Sweden but quickly gave up, then i found this forum and found a lot of good well written information, but i can't really seem to find the solution to my problem.

This is what happened,

I drove my vw Caddy mk2 2001 1.9tdi ALH when it all of sa sudden cut out going down the road, it started right up and drove for a few kilometers and then once again cut out, but this time it just started for half of a second and then stalled, i took it on a trailer home and tried starting it again but it justs starts for half a second and stalls.

I changed the 109 relay for a brand new grey one, now i notice that the GP light doesn't light up every time i turn the key, when it doesn't light up the car is stone dead, but when it does light up i makes that half a second jump start but then cuts out immeaditly.

I took the battery out, made sure the ground was good at the tray, tried searching for bad leads and such but I'm quite lost at the moment.

Can it be something with the immobilizer? i have that separate box underneath the dash.

Any ideas or tips would be great!

Best regards

If that glow plug light doesn’t come on then the 109 is the presumed culprit. You said however that you changed that out and now you notice it doesn’t come on all the time?

Was the glow plug light working all the time before the new relay?

You could try another new 109 they are cheap enough, however I’m unsure of whats available over there so you may want to buy one from the dealer versus amazon cheap junk.

Are there any other systems that are not working? Radio, headlights or anything else. It is possible that your ignition is not working as it should. They are a fairly easy change out also. I believe there is a write up in the tdi 101 section.

Before I condemned the ignition I would do an OEM 109 relay if that wasn’t what you’ve already done.

Thanks for the reply

The GP Light has always worked everytime ive turned the key before this cute out thing happend , there was a white 109 relay before so i thought that it must be the cause so i bought a oem grey relay at VW over here.

However the GP Light problem is the same with both relays at the moment.

I will try to find someone with vagcom this week and get some more information in whats happening.

Forgott to mention that the days before it stalled completley it started acting weird when downshifting in corners and such, When giving throttle on 2nd gear out of a corner it started jumping like it shut off and on rapidly.
Thought it could have something to do with the problem.

Radio, headlights work fine.

Check fuse 176 in the box above the battery. (it's 110 amps.
Maybe take it out and clean the connections for it.

In the fuse panel inside the car check fuses 29, 43, 32, and 34.
Pull all of them & check for corrosion.
Look in the fuse slots as best you can and check there for corrosion also.

I'm thinking maybe a loose connection or corroded wire starting to go.
You did clean the grounds under the battery, not just look at them, right?
If that ground is bad anything that grounds to the battery is bad.

Thanks for all help

I found the problem and it runs perfect now!
In the wintertime they put salt on the roads here,
And Salt, very very much salt had made its way inside the ecu that is located under the windshield , i bought IPA alcohol and cleand it off with a toothbrush.

If I knew how to upload pictures i would, it was a horrific sight!

I will continue read this great forum, very fine information and tips here.

Best regards

Instructions for pic upload in my signature
or my shortened version:
Log in again at pics.tdiclub.com
Select Upload button, follow prompts (check your file type)
At the end, harvest the url to use as a link for your post
Note there are 3 sizes with separate urls. For large data use the thumbnail, it shows the full size when clicked.

This is how it looked when i cracked it open, im going to seal it well so hopefully this doesnt happen again!

Symptoms this problem gave

Engine cutting out milliseconds when downshifting > accelerate through corners making the car jump/ shake rapidly

Engine Cutting out to a stall when driving highway speed, but starting up directly to normal function and can be driven again.

Engine cutting out to stall in highway speed ,starting up but doesnt stay on if you dont rev it.

Engine cutting out to complete stall and doesnt work anymore, starts for a split second , GP light works sometimes and sometimes wont work, when it works it starts up for 0,5 seconds everytime, when it doesnt come on it wont start at all.

If the Ecu looks very corroded and bad on the outside, its very likely that it looks bad on the inside.

Ipa alcohol 99,5% together with a toothbrush and let it dry did the trick for me!

Well, if the repair holds up, great catch! Just be aware the corrosion may have done imperceptible damage that could continue to give you future headaches.
But again, great catch!