2000 New Beetle Intermittent Starting Issue

[Monstabrownie]

Hello,

I've seen this problem posted on a few forums but never been properly answered.

I have a 2000 Beetle TDI 5 speed and it has developed one strange quirk over the last few weeks.

Sometimes when I put the key in and turn it to the "on" position, the dash lights up except for the glow plug light and she will crank and crank but never start. You can't even push-start it if that light doesn't come on.

If I take the key off and back on a bunch of times, EVENTUALLY the glow plug light will flash, there's an audible "Click" sound, and she will fire up in like a single crank.

I have no idea why this is happening. Once she starts, it runs great with no problems. Things I've checked/done:

Relay 109 replaced
All fuses checked, none are blown

Any ideas? From what I've gathered it could be a bad ignition switch, load reduction relay, or the ECM could be buggered. I have a multimeter and a test light to test things but I don't really know how to use them, just so you know in advance.

Thanks!

 

[Tdijarhead]

Sounds like the ignition switch.

Ignition Switch replacement DIY

www.newbeetle.org

 

[Monstabrownie]

Sounds like the ignition switch.

Ignition Switch replacement DIY

www.newbeetle.org

Have one on the way. Will update after I slap the thing in there.

 

[Monstabrownie]

Sounds like the ignition switch.

Ignition Switch replacement DIY

www.newbeetle.org

Put it in the new Ignition switch annddddd....

It didn't work.

Going to replace the GP harness and see what that does but if anyone has any other ideas in the meantime please share.

 

[Vince Waldon]

Glow plugs are not required in the summer for a TDI in good condition... might make sense to save your money and keep troubleshooting until you find the true culprit, and spend it there.

The intermittent nature really does sound mechanical... like an ignition switch or Relay 109... both of which you've now tried. Perhaps a corroded connector on either of those two systems?

When you're cranking but no start is the tach bouncing slightly? (crank sensor)

 

[Monstabrownie]

Glow plugs are not required in the summer for a TDI in good condition... might make sense to save your money and keep troubleshooting until you find the true culprit, and spend it there.

The intermittent nature really does sound mechanical... like an ignition switch or Relay 109... both of which you've now tried. Perhaps a corroded connector on either of those two systems?

When you're cranking but no start is the tach bouncing slightly? (crank sensor)

No actually. Stays stock still on the dash.

It works perfectly fine when the car starts and when it's running, though.

Also, I thought 2000's didn't have crank sensors? Or is that a different one

P.s. I got the harness for $20 and the old one was cracking anyway, figure it can't hurt.

 

[JETaah]

Engine ground? Top front bolt on the transmission to engine joint.
All the engines have a crank sensors. ALH won’t run without it.

 

[Vince Waldon]

No tach when the car will crank but won't start but tach when the car will crank and then start points a pretty strong finger at the crank sensor.

The good news is that they're not that expensive and not that hard to replace.

 

[oilhammer]

NBs melt the ignition switch connector, quite common. No idea why, the G/J don't do that. Something with the way the loads are carried on the NB that makes them different. Have to build a whole new pigtail and splice it in to the dash harness, and leave enough room to fit it all up under the column covers.

 

[Monstabrownie]

No tach when the car will crank but won't start but tach when the car will crank and then start points a pretty strong finger at the crank sensor.

The good news is that they're not that expensive and not that hard to replace.

Is there a guide/pictures out there anywhere for this? I can only find ones online for the 2.0.

 

[Monstabrownie]

NBs melt the ignition switch connector, quite common. No idea why, the G/J don't do that. Something with the way the loads are carried on the NB that makes them different. Have to build a whole new pigtail and splice it in to the dash harness, and leave enough room to fit it all up under the column covers.

Hopefully it's the crank sensor, but if not can you go into detail a bit more? I don't quite understand the technical jargon you're using there.

 

[Vince Waldon]

"ALH crank sensor replacement" on YouTube or Google should give you lots to go on.

 

[oilhammer]

Google helps:

melted new beetle ignition switch - Google Search

Very common issue. I've done dozens of them.

 

[JETaah]

Google helps:

melted new beetle ignition switch - Google Search

Very common issue. I've done dozens of them.

Do you know if the pigtail from a Jetta or Golf work on the Beetle? Gas or diesel the same? If so, that should make it more easily found in a salvage yard.

 

[oilhammer]

Connector shell is the same, but pin assignment and wires may not be. I always build a new one from scratch with new shells and repair wires.

 

[Monstabrownie]

I got in touch with someone who has a VCDS and I got a lot of codes:

00849
01314
01315
17978

I don't understand how all of these fit together...

When the car starts there is no immobilizer symptoms.

The ignition switch is new. So I don't know how 00849 could show up.

I don't even know where to begin honestly

 

[Vince Waldon]

When you clear the codes do they all come back? Codes don't reset by themselves after repairs have been made and have to be cleared manually.

 

[Monstabrownie]

Cleared codes, drove around until CEL came back on; here's what I got.

01314 - Engine Control Module

49-10 - No Communications - Intermittent

19586 - EGR System Regulation Range Exceeded

P3130 - 35-10 - - - Intermittent

17964 - Charge Pressure Control: Negative Deviation

P1556 - 35-00 - - - Intermittent

I replaced the ignition pigtail as described above as well. Still haven't done the CPS, though.

 

[Monstabrownie]

SOLVED!!!!!!!!!!

It was a bad ECU, believe it or not. I got a replacement with a deleted IMMO off ebay for $240 and she is a SMOOTH machine now.

Now to make some biodiesel....

 

[oilhammer]

Strange, but thanks for reporting back! Glad you got it fixed!