TDi 170 Rough idle/smoking/hesitation - FIXED! Unicorn motor dev' remap :-)


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Jul 28, 2013
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East Lancs
Hi everyone, I posted a few weeks ago about the problems I was experiencing with my B7 A4 TDI 170 s-line quattro special edition.

I had rough/lumpy idle, excessive black smoke, hesitation/flat spots, rough running and a very weird error code (000000 - SAE - Reserved by Document ISO 15031-6).

I had a big birthday surprise on Saturday as my wife had secretly arranged to have my car remapped by Rick at Unicorn Motor Developments including DPF and EGR removal/delete. Rick has done a great job, it's now the car Audi should have made! :)

If anybody is at the point where they're wondering whether to take the plunge and get a remap with DPF/EGR removal then my advice is to categorically go for it!

With regards to the unusual error code, Rick confirmed my suspicions - the car had already been tampered with. The DPF had been partially gutted and the ECU had been remapped - terribly as it turns out! So it appears this error code is the result of somebody using a crap piece of software to try and delete the DPF.

The power delivery is much more smooth and progressive and the increase in low-end torque is very noticeable. At points on my usual journey to work over the Pennines, where I previously had to drop down into second gear up some very short steep hills, I can now stay in third gear because the car pulls like a blooming freight train at low RPM, the torque increase is brilliant. I don't know what the exact increase in torque is but Rick said he conservatively estimates bhp to be up to 205 with this remap and the last one he had on a rolling road was running at 215bhp.

Overtaking farmers bobbing about in their tractors on short narrow stretches of road can now be done without running out of puff and having to change gear. (When it's safe to do so of course!)

I've only driven about 100 miles since the remap but MPG does seem to have improved, I'll report back on this when the temptation to keep blipping the throttle and put a grin on my face wears off.

Another thing I've noticed since the EGR valve has been blanked off is the engine shuts off immediately with no judder, it's just like switching a petrol engine off.

Servicing will probably be cheaper as well because I no longer have to use VW 507 00 spec oil for the DPF.

Thanks very much for your help Rick, the car is much better to drive. :)
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i have the smoke issue when the car is on idle

its audi a4 2.0tdi quattro 2007

has the issue been fixed by this remap?

pls do report back

many thanks
Hi Shu, yes this issue has been fixed with the EGR valve being deleted/removed. Have you looked at your EGR valve or had it cleaned? There are plenty of posts on this forum explaining how to do this, they get clogged up easily. Mine had been cleaned out twice and was still being problematic so I just got it sorted with the remap. There are several reasons why your car might be smoking like it is so it would be worth narrowing it down first if you can.
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