ZT190 accelerator sticks!

[chris watton]

We have an MGZT 190 (2003), and it has been great since we bought it a couple of months ago. However, today, on the M5, the accelerator stuck – you could take your foot off the pedal, and it carried on going faster! We came off the Tewksbury junction, put it in neutral, but it revved all the way up to 7000rpm! It was only after pushing the accelerator a few times that the revs died down back to normal. This happened a couple of times. There were no warning lights showing on the dashboard, so I assume it wasn’t ECU related.
Would this be a throttle cable/mechanism problem, and has anyone else had this problem?

ETA - It's a ZTT-190, not a ZT - although I'm sure they're both the same...

Edited by chris watton on Sunday 26th December 18:06

[Kermit power]

Maybe just the cable getting a bit sticky inside the sheathing? I know one of the other 260 owners had a similar issue, which he fixed by disconnecting the cable at the engine end, securing it to the raised bonnet with cable ties and then running some lubricating oil down the inside of the cable. He just left it like that for a couple of hours to soak through.

[chris watton]

Kermit power said:

Maybe just the cable getting a bit sticky inside the sheathing? I know one of the other 260 owners had a similar issue, which he fixed by disconnecting the cable at the engine end, securing it to the raised bonnet with cable ties and then running some lubricating oil down the inside of the cable. He just left it like that for a couple of hours to soak through.

Thank you for that. Makes sense. I must point out that it has been bitterly cold here, we were driving in temps of -8. Wonder if that had anything to do with it.

[Mike 820]

I had exactly the same thing before christmas Chris.

On the m61 my throttle cable got stuck on. Like you I first checked the pedal and it wasnt caught on the floor mat. It was -8 as well funily enough.

I checked the cable and it moves freely. It has happened once last week since, but again it was -5. Im fairly sure its related to the cold. Sorry I cant give you an exact cure.

Edited by Mike 820 on Wednesday 29th December 19:27

[chris watton]

Mike 820 said:

I had exactly the same thing before christmas Chris.

On the m61 my throttle cable got stuck on. Like you I first checked the pedal and it wasnt caught on the floor mat. It was -8 as well funily enough.

I checked the cable and it moves freely. It has happened once last week since, but again it was -5. Im fairly sure its related to the cold. Sorry I cant give you an exact cure.

Edited by Mike 820 on Wednesday 29th December 19:27

Must be (low) temperature related. It hasn't happened again since it's got slightly warmer (or should that be 'not as cold')

Glad we're not the only ones!

Cheers

[perdu]

I'm glad it seems a bit better now

One thing you might be able to do (Sorry, no ZT handy to take a look ) is disconnect the cable up at the engine end, now while temperatures are milder and fill the cable sheath with WD40, letting it run out at the bottom (leave a dollop of rag under the throttle pedal to catch drips)

This will have the benefit of lubing the inner cable anyway but also as WD is a Water Dispersant it could get any droplets of H2O out of the way so in future it doesn't stand much chance of freezing inside and letting it stick

I had wondered if the cable was acting as an earth and getting warm and sticky but the water in it scenario seems likelier