Missing when cold

[PoloGIT]

Ok fellas, anything else I can check with VCDS before I go systematically working through the hardware? This issue is getting very annoying and embarrassing when I pull out and have no power or start bunny hopping down the road. I just want to get back to enjoying my POG!

[h100vw]

Do me a set of logs again. And send them over. Also look at block 032 and screenshot it. If it's more than few percent out. Could indicate a leak somewhere

[PoloGIT]

Gav, sorry, I missed your post the other day :-/ If you go back to just before that post, you will see a screenshot I did that had block 032 in it. You'll have to tell me which field references LTFT...if it's the second field, then that doesn't seem to deviate much from about 20, whether cold, hot, cruising, pushing or idling.

Looking at the state of the tailpipe, I would say it is probably is running rich, unless it's just some unburnt fuel from when it misses.

I'll try get those logs over to you in the weekend. Cheers

[h100vw]

Missed that. So unless i have fuel trim theory backwards, it's adding at idle meaning it's sucking in unmetered air after the MAF. But then removing a **** load of fuel at part throttle. Which says it rich, could be a decent boost leak.

[PoloGIT]

Righto, so managed to drag myself away from the Datsun and do a fair bit of troubleshooting on this of late. A couple of weeks ago, after looking and listening in vane for boost leaks, I whipped out the injectors and gave them a clean out. Initial thoughts were I'd sorted it, as it appeared to be running better. About 2 days later though, it started to run like crap again, if less often than before.

Next step, I installed a boost gauge to help troubleshoot, well that and because it's been sitting in the shed for a while waiting for me to pull finger!



Bugger me, although it was showing vacuum in the right range, about 20-25 in/hg, boost was only showing a max of about 13PSI. As she's just a cheapo electronic boost gauge, I wasn't that confident about those figures. So I followed up with some logging and this was the output from ECUxPlot, clearly showing it tapping out at about 15PSI or so (I'm not sure if the ~2PSI discrepancy between the gauge and logs should be expected?):



Clearly something's not right. TBC

[PoloGIT]

Time to get serious about finding a boost leak...





TBC

[PoloGIT]

Here it is... Turbo hotside rubber hose hiding inside that fabric heat shield. That split is about 50mm long. Absolutely stoked to have found it and hoping I can get a replacement quick and be back to a clean running ~20PSI pronto! Thanks guys for your help and suggestions. It's a real pain to troubleshoot this stuff, but hopefully this helps someone else.

[h100vw]

Epic win there Dunc. Hope you can find a secondhand pipe from somewhere.

06A 145 832 M should be $114 AUD over here


I just googled it and the Golf GTI has the same part. Its not Polo specific

[Nikogti]

Try this stuff from supercheap for a quick fix until your part arrives. Works good.

Calibre Tape-It Self-Fusing Silicone Tape - Clear, 3m x 25mm | Supercheap Auto
Calibre Tape-It Self-Fusing Silicone Tape - Clear, 3m x 25mm | Supercheap Auto

[sambb]

Yeah nice find. I built a tester like yours a while back but never got around to buying a compressor. I have a spare (90,000km) one of those hoses if you get stuck.

[PoloGIT]

Thanks guys. Is this one not a common problem with those of us running plenty of boost? All sorted now and I can't believe how much better it is and how I thought it was running fine before when under boost...I guess the split got gradually worse and I just didn't notice the power loss...but now suddenly I'm in love with my POG again

Epic win there Dunc. Hope you can find a secondhand pipe from somewhere.

06A 145 832 M should be $114 AUD over here


I just googled it and the Golf GTI has the same part. Its not Polo specific

I didn't see your edit there, Gav, about it being the same as the Golf until later. I actually went and ordered a new one from VW, about the same price as what you said above, 2 week wait, but then saw your edit, cancelled the order and ended up finding a used one local from an Audi TT 180, $20!

Yeah nice find. I built a tester like yours a while back but never got around to buying a compressor. I have a spare (90,000km) one of those hoses if you get stuck.

The tester I made there was still letting air leak into the engine, I guess via an EGR valve and/or crankcase breather or something, so for less obvious leaks than the one I had, you'd want to use a puck or two to block off one or two of those other pipes. Not sure how I'd survive without my compressor