1.8T AUM Combi budget sleeper build [caution - long and boring read :) ]

[Juka]

Hi all, a new car is in the stable, making good company to the Fabia RS the wife is now driving. After 1.5 years of seeking a good 1.8T AUM Octavia, finally one popped up and I bought it, an 2001 Combi 1.8T with the newer AUM engine. I tried at least a dozen others, most were really bad, some okay (ish), and one good one got snatched in front of my nose by a car flipper, I hate them :S I want to make it a family budget sleeper, nothing fancy, has to be reliable and will be driven daily.

 

I'm looking at keeping everything stock (intake/exhaust) and doing a custom remap stage 1 getting 200~210 hp, and at least 300 Nm. My first "mods" are to get the car mechanically in factory mint condition to complement the remap and get best results possible, this is where I need youz guyz advice on what to look out for and fix preventively.

 

My list goes something like this in relation to what I've read about weak points on the 1.8T's, please add what you think is needed, and with part numbers if possible, comments welcome on wether to do something or not:

 

• dropping the oil pan and cleaning the oil pickup tube (preventive)
• turbo braided hose line change (preventive)
• oil breather pipes and PCV renewal (PCV good, breather hose broken, stinks gasoline when idling)

          - I see kits for this such as: https://www.ebay.com/itm/6pcs-Kit-Engine-Crankcase-Breather-Hose-For-VW-Golf-Jetta-MK4-Audi-A4-TT-1-8T/401261248612?epid=501457403&hash=item5d6d08c064:g:XXkAAOSwAaJaAbO2 is that any good or should I buy separate parts brand name, or just change the broken ones?

• valve cover gasket (leaking)

 - here I also want to change as much stuff, my mechanic mentioned a few more seals and checks while it's being done, I want to do everything thoroughly while it's all apart

• vacuum hoses - complete set (mechanic told me they will probably break during valve cover resealing, so he will anyway change all of them) 
• EVAP system, hoses broke on the carbon filter
• SAI pump good, one mount broke off, what can I renew here to make the system good as new?
• I used Aral Tronic 5W40 on the TDI's for a long time, very satisfied with it, would it make sense to use it on the 1.8T, what would you recommend?
• The car came with Landi Renzo LPG installed, works flawlessly, mechanic recommended to halve the oil intervals due to higher temperature burning on LPG thus wearing out the oil more (eg. 7.5 kkm oil+oil filter, 15 kkm oil+all filters), what do you think?
• Only real fault with the car is the AC compressor clutch failing, the AC itself works but makes horrible grinding noise and the fans don't turn on with the AC - might get away with just clutch replacement but recommendation is to get a new AC compressor and fans installed ~700 EUR fix ouch. Opinions?
• other...

 

Apart from that everything else is wear n' tear (thermostat, suspension items...) and I'm lucky the previous owner took care about regular oil changes and got a new cam and aux belt with tensioners, waterpump etc. 

 

Attached a few pictures of my Škoda stable, the cars actually complement each other, both black, with stock xenons, looks cool. I just love the subtle looks on the Octavia, it's the perfect sleeper.

 

@robek85 thanks for the initial inputs, neighbour

 

 

 

 

[J.R.]

I slept many times in my MK1. I would advise an inflatable mattress and some home made insulated window blinds.

 

Only joking in case the humour does not translate!

 

Nice looking car, makes me miss my MK1, far more stylish than the MK2.

[robek85]

Welcome to the club 😃

[Breezy_Pete]

Fixing the fans might be much cheaper than you've suggested. 

There's a common fault involving the internal low-speed resistor; can be replaced with an external one.

Have you checked fuses?

 

 

Edited 3 March, 2020 by Wino

[Juka]

On 03/03/2020 at 09:10, Wino said:

Fixing the fans might be much cheaper than you've suggested. 

There's a common fault involving the internal low-speed resistor; can be replaced with an external one.

Have you checked fuses?

 

 

Thanks, I actually had capital AC system failure due to these f***ing low speed fans not working on the Fabia (2005). Fix like this is few bucks, my whole system was shot and full of metal shards. New everything, they barely saved the evaporator in the cabin.

 

I have checked the fuses on the battery, they all look good, should I check the ones in the cabin?

 

Unfortunately, I really have no DIY time so I guess new fans for me :(

[Breezy_Pete]

I'll have a look soon to see if any cabin fuses are involved, but I think probably not.

[Juka]

No other comments regarding preventive maintenance on a 1.8T, what else should I inspect? 😞 Plz guys, I really want to make it a mint condition car.

 

I've slowly started fixing it up, quite a lot of tiny things (door hinge, 3rd brake light, front right blinker, cleaning out the crud in wheel arches...) makes me happy.

 

@Wino Fitted two brand new fans, total cost about ~120 Euro, the original ones had busted low speed on both, all rusty, who knows when they failed...

[Juka]

Short story: 235/45R17 fits nicely on my stock suspension Octavia 1.8T. Also looks nice and aggresive on Avus Audi S3 17" rims (wider and more offset than stock 17" spyder rims), my intention of keeping the car as a sleeper just went down the drain. Before/after pics below.

 

Long story:

 

So after running around the whole year incognito mode, steel 15" rims 195/65R15 w/o hubcaps, enjoying myself, and faces of unsuspecting BMW drivers - I've done the famous AUM stage 1 remap to 210 hp after which the tyres can't handle the acceleration in first two gears, and made the car almost impossible to accelerate/drive when raining so I had to do something about the grip. The idea was to get ANY cheapo/trash/dank - undamaged 17" rim to fit the standard 225/45R17, I really wanted some Fe rims (again, incognito-sleeper style), but they don't exist in 57,1 5x100 dimensions (there is a 5x100 17" steel rim, but it's for some huge Renault, and I think it's only for the spare wheel, making the rim witdh in range of lol-J). There is a lot to choose in 16" region, but 205 is just too small for the power the car makes, IMHO. I even looked into 215 combinations in 16" and not only there is no performance tyre in this dimension, it's ridiculously expensive.

 

Mind you, I'm running standard setup on all four corners - Bilstein B4 shocks, Bilstein OEM springs - no lowering, I was a click away to order the heightened springs!! I'm never going to be a style-slave, laughing while just casually cruising over speedbumps whereas dropped GTI's/Type-R's/RS's have to do the diagonal idle+clutch maneuvers

 

I also fancied the idea of fitting larger tyres on it, 235/45R17, my flow of thought was the following, pros/cons:

+ more grip ofcourse

+ more offset/scrub radius - more initial turn-in, responsiveness on the steering wheel

+ more accurate speedo

+ keeping comfort (decent sidewall)

+ less wear

+ overall height of car increased, again more comfort

+ tyre "attack angle" smaller, making it easier to run over obstacles (eg. curbs, speed-bumps), again, even more comfort (you probably noticed a pattern, I'm anti-style oriented, pro-sleeper/comfort style :))

+ visually I always liked seeing fat-meaty tyres in the back

+ only slightly more expensive than 225/45R17

- very little experience on Octavia mk1 + that tyre combo, some say it fit's others say it doesn't

- much heavier

- slower acceleration

- possible rubbing

- worse fuel consumption (it's LPG-ed and it's dirt cheap here in Croatia)

 

Anyway, I managed to snatch a great deal on original 17" Audi S3 "Avus" Alu rims (made by Ronal, Made in Germany), bonus points: they are 6 mm more offset and 0.5J wider than standard rims 17" Spyders, making way for wider tyre! All the calculations point to no rubbing with 235/45R17 ( https://www.wheel-size.com/calc/?wheel1=195-65-15X6ET38&wheel2=235-45-17X7.5ET32&fcl=50mm&scl=50mm&wcl=30mm&sr=0mm left is my standard setup, right is Avus). But a real life test is needed, I don't want to risk spending €€€'s and putting new summer 235's just to find out they don't fit/rub! So I also managed to snatch winter tyres dirt cheap (almost free), Hankook Winter iCept 235/45R17 DOT2016 halfway worn - perfect for testing out the setup - if it fits, great, if it doesn't I spent a few hours and a few bucks demistifying it.

 

Putting on just the rim on the car was a shock, when lifted, viusally seems like ~2 cm more than outline of car, ouch - on the inside though, quite a lot of space; the guys at the wheel shop rolled they eyes constantly We fitted the tyre rim combo, dropped the car, did a run around the lot full lock..... Purrrrfect, no rubbing, and when car is sitting on it's own it's just right, slightly out of car outline, this will be a slight pain to homologate tho.

 

Inital impressions after a few runs:

+/- wheels are a stunner, so much for my incognito/sleeper preferences, honestly, looks much more aggressive than the RS... I guess I'll deal with it.

+ very soft and controlled wheelhop, car doesn't want to break apart when you loose grip

+ comfortable

+ better turn-in, much less wobbly car

- awfully heavy, steel rims+tyre 16.6 kg, alu rims+tyre 22.4 kg, ouch, you can see the pictures below, but I'll write up for any google search guys to stumble upon this, I find it invaluable info:

 - 235/45R17 Hankook Winter iCept 1/2 worn: 10.5 kg

 - Audi S3 Ronal Alu 17" rims: 11.7 kg

 - 17" above tyre+rim combo: 22.4 kg

 - 15" stock steel rim + 195/65R15 Pirelli P7 combo: 16.6 kg

- noticeably "slower", feeling is the inital throttle response is much lazier, not so agressive as on 15"; can't really blame it, the car couldn't even accelerate before

 

Didn't try the twisties yet, but the idea is to run around a few weeks and notice how the car behaves and if there will be no rubbing in spring get the Goodyears F1 Assy 5 in 235/45R17.

 

@Madket

Edited 13 December, 2020 by Juka
added offset closeup

[skinnyman]

On 13/12/2020 at 17:31, Juka said:

awfully heavy, steel rims+tyre 16.6 kg, alu rims+tyre 22.4 kg, ouch

 

This is an interesting thread & good to see someone else making an effort with their Mk1.

 

As for the wheels, I've done the same as you in the past.  The car looks better on the Avus rims but as you say, they're heavy.  I once put some Audi 'fat fives' on my old Mk1 and they ruined the ride & handling.  They looked good but after a few days I went back to the standard Spiders and the car felt so much better straight away. 

 

I've currently got a set of 18" OZ Ultraleggera on the car which strike a good balance between looks and weight.  They're lighter than the standard Spider rims but they aren't cheap.  I've also got a set of 17" Pro Race 1.2 in the garage and again, they're light but seeing as I bought them new, they cost me quite a bit when new tyres were added.  I have a problem when it comes to wheels and have spent a fortune over the years on my cars trying to find the sweet spot between looks, weight and cost.

 

Keep the posts coming.

 

 

Edited 28 December, 2020 by skinnyman

[matt_theforce]

I too did the 17" S3 alloy change on my Octavia, they didn't stay on long before I went back to the standard 16" Elegance alloys

 

My Octavia was sat on KW Springs & Dampers, the mk1 Octavia's make fantastic looking sleepers 

 

I can't comment on the 1.8t maintenance/tuning as I only had my mk1 vrs for 18months before buying the above PD130, that said, my PD130 had 185bhp & 343ftlb and handled the power fine with the standard 205/55/16 tyre size & allows the 312mm brake upgrade to fit nicely

Edited 29 December, 2020 by DarkPeakCycles

[Juka]

So much for the 17" Avus... Failed homologation, fronts are outside the car silhuette, car is basically illegal to drive with them. After much contemplating what to do, fit 225 tyres, do camber adjustment, extend the flares, even mill down the rims - in the end got rid of them (made good profit lol) and found a great deal on original 16" Ride wheels with Pirellis P7 205/55R16 already fitted, great condition of tyres and rims. Saved myself a ton of time and nerves. 

 

Weight of the set is 16.9 kg, exactly the same as 15" steel rims and tyres. Unlike horridly heavy 22.4 kg 17's.

 

The initial turn in and car wobbliness was better on the 17's, everything else is better on 16's, especially acceleration (even grip, but probably due to good summer tyres unlike dead winters on 235). 

 

Now I'm back at my sleeper roots, the car looks just so natural, clean and calm, I look at it quite often

 

I also took a video of 3rd gear acceleration, it's just insane IMO. Can't really tell from shaky video but I put numbers below, roughly ~4s 80-120 km/h. Thats well in GTI territory, if not better. 

 

 

[Juka]

My lovely sleeper is fine, running better than ever, although I have a serious comfort issue I hope fellow briskodians can help with.

 

The car is utterly and horribly crashy, trashy and noisy to ride, help!

 

It's stiff and uncomfortable, which I can actually live with, but the noise it's making over the invisible bumps (smallest crevices or literally road markings) like TDNNnnn TDDNnnn, the whole car is ringing like a church bell. It got even worse as the weather got colder now.

 

Car is 100% standard suspension, with brand new Bilstein B4 shocks&springs on all four corners, with 16" rims and DOT2019 Michelin Primacy 4 in front, DOT2017 Pirelli P7 in the back.

 

Currently it's at my mechanic where we are debugging what is wrong, I said change every possible rubber bushing you can find (that is how desperate I am). My front bushings were busted, left swaybar link, changing everything with Lemforder OEM ones. Rear bushings are next - but he fears it's the shocks  are too stiff (can't blame him, I really don't actually like the Bilsteins, I fell for the brand honestly), there is also some play in the top strut caps (which were also fitted new and Bilstein). So I'm also thinking of changing to new shocks even though these are 1yr old, he did say oil shocks are more comfy than gas ones. Looking at Monroe or Sachs oil ones now...

 

Having driven many Octavias (buying my mom also a 1.8T one, that's how much I love them), they drive like real limousines, quiet and soft.

 

What do you guys reckon could be the reason for this crashy trashy ride, and what could solve this? I just want a quiet and comfy ride.

[Juka]

Anyone still driving a 1.8T Octavia 1 in 2022? To reply to myself about the suspension road noise issue, I solved it and done it two stages:

 

1. changed every suspension item possible for brand new one - Lemforder all bushings, front big and small ones, swaybar links and bushings, and rear beam bushings - those were a PITA to change and was charged whole day of work for them - ouch.

• the road noise was improved but only at lower speed, under 20 km/h it was literally inaudible over anything, but above 20 was more or less the same (the steering input was also a bit improved). Definitely too costly for only slight improvement in road noise. The low speed improvement did suspect to me that it had something to do with shock rebound...

2. changed all four shocks to Sachs OEM ones (front oil, rear gas).

• desperate after ditching a whole lot €€€ for "nothing"... black Friday came in nicely, almost 50% on new Sachs shocks, got them for 160ish EUR all four corners. After changing them - world of difference, road noise is halved, and harshness was gone - to anyone reading - Bilstein B4 shocks are pure rubbish, do not buy them! If I knew this two years ago, I'd go with Sachs in the first place and just change the broken bushings for a few € not spending €€€ for everything.

 

Main takeaway, if you want a plush and pleasant ride go with Sachs oil shocks and stock springs; I also have the "Bilstein OEM springs" but fear they are too stiff as well, as the car is still not as comfortable as I'd like...

 

Hope my post(s) help people not make the same mistakes as I did "I just want a standard comfy suspension, hey look, Bilstein stock setup, I like the Bilstein badge, they cost the same as other brands, I'll fit those", biggest mistake ever.

[dubDEAN]

16 hours ago, Juka said:

Anyone still driving a 1.8T Octavia 1 in 2022? To reply to myself about the suspension road noise issue, I solved it and done it two stages:

 

1. changed every suspension item possible for brand new one - Lemforder all bushings, front big and small ones, swaybar links and bushings, and rear beam bushings - those were a PITA to change and was charged whole day of work for them - ouch.

• the road noise was improved but only at lower speed, under 20 km/h it was literally inaudible over anything, but above 20 was more or less the same (the steering input was also a bit improved). Definitely too costly for only slight improvement in road noise. The low speed improvement did suspect to me that it had something to do with shock rebound...

2. changed all four shocks to Sachs OEM ones (front oil, rear gas).

• desperate after ditching a whole lot €€€ for "nothing"... black Friday came in nicely, almost 50% on new Sachs shocks, got them for 160ish EUR all four corners. After changing them - world of difference, road noise is halved, and harshness was gone - to anyone reading - Bilstein B4 shocks are pure rubbish, do not buy them! If I knew this two years ago, I'd go with Sachs in the first place and just change the broken bushings for a few € not spending €€€ for everything.

 

Main takeaway, if you want a plush and pleasant ride go with Sachs oil shocks and stock springs; I also have the "Bilstein OEM springs" but fear they are too stiff as well, as the car is still not as comfortable as I'd like...

 

Hope my post(s) help people not make the same mistakes as I did "I just want a standard comfy suspension, hey look, Bilstein stock setup, I like the Bilstein badge, they cost the same as other brands, I'll fit those", biggest mistake ever.

glad you found you problem  as you say Bilstein are a great brand but i'm guessing not as a stock replacement 

[MiniNinjaRob]

On 06/01/2022 at 22:16, Juka said:

Anyone still driving a 1.8T Octavia 1 in 2022? To reply to myself about the suspension road noise issue, I solved it and done it two stages:

 

1. changed every suspension item possible for brand new one - Lemforder all bushings, front big and small ones, swaybar links and bushings, and rear beam bushings - those were a PITA to change and was charged whole day of work for them - ouch.

• the road noise was improved but only at lower speed, under 20 km/h it was literally inaudible over anything, but above 20 was more or less the same (the steering input was also a bit improved). Definitely too costly for only slight improvement in road noise. The low speed improvement did suspect to me that it had something to do with shock rebound...

2. changed all four shocks to Sachs OEM ones (front oil, rear gas).

• desperate after ditching a whole lot €€€ for "nothing"... black Friday came in nicely, almost 50% on new Sachs shocks, got them for 160ish EUR all four corners. After changing them - world of difference, road noise is halved, and harshness was gone - to anyone reading - Bilstein B4 shocks are pure rubbish, do not buy them! If I knew this two years ago, I'd go with Sachs in the first place and just change the broken bushings for a few € not spending €€€ for everything.

 

Main takeaway, if you want a plush and pleasant ride go with Sachs oil shocks and stock springs; I also have the "Bilstein OEM springs" but fear they are too stiff as well, as the car is still not as comfortable as I'd like...

 

Hope my post(s) help people not make the same mistakes as I did "I just want a standard comfy suspension, hey look, Bilstein stock setup, I like the Bilstein badge, they cost the same as other brands, I'll fit those", biggest mistake ever.

I have B4s on my Volvo 940 and they are brilliant, so maybe it depends on the use case. 

[chrisrhayes]

Nice to see shiny Mk1s. I fitted 4 Bilstein shocks to mine recently and the ride improved.
Still soft, but more... controlled. The ones being replaced were well past it though. I think I went for the lower engine mount too, which improved the general driving feel.

 

The worst suspension I've driven was an old Citroën BX GTI with completely shot air suspension: like a pogo stick, but less controlled! I used to feel physically sick after 20 mins of driving it...