Basically this is what I sent to Evo for their Buyers Guide. I'm not saying its definative or indeed 100% correct. More like my opinion of the Cars. Its biased towards the GTA but most of what’s said here could apply to 156 V6’s too.
I'm Happy to amend it in light of your comments.
Bonnet Catches. (147's and 156's)
This should be a familiar topic, but given its importance and potential to cause an accident I placed it at the top of my list.
The release mechanism is greased from new and picks up road dirt and all sorts of other gunk. It eventually gets to the point were only the secondary latch engages as the primary catch is gummed up. The end result is that the bonnet, usually on the motorway, flips and smashes into the screen and roof. Very scary and not that uncommon.
Alfa have issued several recalls for this problem, their most common solution is to degrease, clean and refit an existing mechanism. Some catches have been replaced. Later model 147's have a plastic catch instead of a steel one which seems to have eased the problem but not entirely solved it.
The bottom line is you need to drop the bonnet shut and give the leading edge a firm tug to ensure its shut properly. They also need regular doses of wd40. I wouldn’t recommend the use of white grease in this location.
Also, when buying look from damage to the roof, if it has had a bonnet flip its not uncommon for the roof to have been repair rather than replaced which means bubbling above the windscreen, ripples in the roof etc and a high possibility of water ingress around the screen which makes the car smell.
Engine
Water Pump. Like nearly every other V6 they have a plastic impellor. They split over time radially and eventually fail. They're driven off the aux belt but replacement requires the cam belt to be removed. So you're into a cambelt, tensioner and two idler pullies as well as its an expensive job in terms of labour. The 3.0 GTV pump has a metal impellor and solves this issue. There are no compatability issues with this. I have found that if you use a pattern pump, the cambelt tensioing tool will not fit on them......crow bar......
Cam belt replacent requires CNC'd cam locks that are unique to the GTA engine - different inlet cam profile and the exhust cam is timed slightly different. They're not plenty-full and I suspect a dodgy indie will try to use standard locks as they nearly fit, that or tipp-ex marks.
MAF - Like every other 156 and 147, air flow meters should be considered a consumable item. They last around 70k miles. Its unique to the GTA and as a result slightly more expensive. Symptoms include flat spots, rough running, poor idleing etc. Brings the engine fault light on and sometimes the car won’t run with the maf connected.
Oil filter. Its a right pain to get at on the 156 v6. Its buried at the back of the engine above the power steering pipes and subframe. Its horrible to get at. The GTA is EVEN worse!!!! Instead of a heat exchanger (coolant / oil) the GTA has an oil cooler mounted on the offside. The pipes are routed under the engine with the P/S pump pipes. God knows how you're supposed to get it out..... And that's the problem. There are more and more 156 v6's appearing with blown engines. Not because they've been run dry of oil or been neglected but because they haven't had their filters changed and they've spun a main bearing. Clack Clack Clack.....
Alfa T-sparks have a growing reputation for being somewhat fragile. IMHO Its because the use copious amounts of oil and nobody ever checks the level. The V6's, GTA's included do use oil particularly if you give them a spanking but they're nothing like as bad. Mine's use a litre in around 3k miles.
Selenia 10w60 is the recommended brew. Its available from stealers @ around £60/5l or on line for half that. At the time of writing Alternative Autos, one of the forum sponsors were selling it for £32+vat. Bargain.
Coolant temp - too low / too high - thermostat. Lots of 156's and 147's running around with cooling issues but they tend to be older models with crumbling radiators. GTA’s are no exception. They getting old enough now.
Fluctuating Idle problems - likely to be a MAF problem or in need of an Throttle / ECU reset:
Battery off 15min, back on, ignition on 2min off, start, idle 15 min, off, italian tune up.
Other than that they really are bullet proof and relish a thrape.
Exhaust
Nothing to report really. Euro 3 compliant - so 4 cats and lambdas. replacing the rear bank primary lambda's supposed to be very awkward but I think they're reliable. Makes a nice noise.
Gearbox / Clutch
Hmmmm. 6 speed V6 box. Different ratios to the 156 V6 box. According to the Eper the diff is the same, but the sun gears have been beefed up. Doesn't seem to have helped things though.
“And to quote another engineer, "it's not a matter of if, but when it will break." Or to be very definite: "The problem is related to a stress concentration factor at the rear and front of the pinion bevel gear tooth. The von-misess stress at 50% throttle is around 900 MPa (about three times the yield strength of the material)"
I’m not going to even pretend I understand that. I do know that diffs are failing – they spit there internals out through the gearbox casing more often in hot climates, Australia for instance. But it does happen here as well. I think Alfa know they have an issue as the undertray features a NACA style duct feeding air directly to the diff casing. I’m pretty sure the undertray is unique to the GTA. Following some heated discussion on AO, I think we all agreed that the diff internals aren’t strong enough. Some were questioning whether the traction control helps things, arguing that is could put some additional shock loading thought the diff.
The good news is that the Q2 torque biasing diff is a straight swap and costs less than £250 direct from Alfa(BARGAIN!!!!) How long it stays at this price is another issue. They’re on back order but AHM (Adie Hawkins) has them on the shelf apparently. I personally missed the boat and have a Quaife diff in mine. It’s a bit unruly. EVO claimed that its stronger than the standard diff but I think its yet to be proven.
Clutch release bearings are a weak point. Possibly identified by a creaking noise. They do get very heavy towards the end of their life. The slave cylinders are also a bit of a problem. The seals go and they start leaking hydraulic fluid. A leak down the front of the gearbox is almost certainly brake fluid (they use the same reservoir) from the slave cylinder. Its cheap and easy to fix though.
Clutch replacement requires removal of the front subframe and therefore a lot of the front suspension as well as the rear exhaust manifold. Massive job.
They did do a selespeed version. I think about 5 have been imported into the UK. With a 6 speed box rather than the usual sele 5 speed box, I’d avoid them like the plague. Selespeed – Italian for HOW MUCH!!!!?
Bodywork
Some potential corrosion issues....See here:
http://www.alfaowner.com/Forum/alfa-...c-warning.html
But don't go off the idea of an Alfa on the basis of previous mid 70's horror stories like "On a quiet night you can HEAR them rusting". That's just not true. All modern Alfa's are galvanised.
Electrics
Not sure about if this has been solved with the facelift dash etc that went in the GTA but 156’s have an air bag lead to the front seats, if it gets dislodged it switches the air bag light on and even if you re-connect it, it remains lit necessitating a trip to the stealers for a reset.
MAF’s have been covered.
Crank sensors fail occasionally. Engine dies when it gets up to temp and refuses to restart until its cooled down. Simple and cheap to fix.
147’s use a system were everything is controlled by computers dotted around the car. AFAIK the computers themselves are reliable. Random electrical faults relating to windows not working etc are more than likely due to a duff battery. Even if the engine starts okay an elderly battery can play havoc with the system.
Suspension
The front lower arm suspension bushes are made out of chocolate. They are a right pain to replace. The double wishbone set up gets in the way. Around £80 – £120 for a new one. I’ve found the best way to change them is to undo the hub nut. Please note a new nut will be required.
The upper wishbones aren’t much better and even worse to replace. About £40 to buy – Alternative Auto’s are again the cheapest source I’ve found.
The rear traverse links wear but it shouldn’t be an issue at this age. The inner mounts are eccentric so it will need tracking after replacement. They’re cheap enough though £20 – £40.
Front Anti Roll Bar. The bushes wear and allow the roll bar to slide from side to side. It makes a hell of a racket. Completely random knocking from the front suspension? Roll bar. About £120 in parts and 3 hours labour – the subframe has to be removed again.
I think Alfa’s claim about quicker steering (Something like 2.2 turns down to 1.8) is somewhat misleading. It is quicker, but they had to further limit its lock (its laughable) to fit bigger wheels.
No known problems with dampers or springs, they’re a bit wobbly when new!
The front uprights (hub carriers) are unique to the GTA. Aside from the brake caliper mount spacing, I reckon they give around 1 degree less negative camber. Probably due to the lower ride height.
Brakes
Up until November 2003, all 156’s and 147 GTA’s left the factory with 305mm front discs and 4 pot LUG MOUNTED brembo calipers.
There’s been all sorts of endless twaddle said about the 305’s, possibly a bad batch of calipers, according to some people, But the top and bottom of it is the 305 set up is prone to warping discs IMHO
Post november 2003, GTA’s were fitted with much more manly 330mm discs and radially mounted brake calipers allegedly from the back of an F360.
They use a more readily available brake pad size, shared with a Mitsi Evo 6 if I recall correctly. Either way Ferrodo DS2500’s are available in this flavour pad.
Alfa have offered a warranty up-grade somewhat reluctantly to some 305 equipped cars, it depended on the service manager and a proven history or brake problems, so its hit and mis as to what’s got what.
In their wisdom alfa said that the 330mm brakes would not fit behind the older softer looking multispoke alloys, only the teledials, and changed the design of the multi spokes to fit. They could have changed the design of the bolts holding the caliper on and got them to fit but hey ho…. So if the car has the older multispokes, 330’s won’t fit.
Hand brake cables seize but not at this age. Not worth worrying about.
Also brake pipe corrosion is known to be a problem on very early 156s. See David C’s sticky thread in the tech lounge/
WHEELS / TYRES
There allegedly was a 16” wheel option but I’ve never seen it.
All 225/45/17
Older Multi spokes (softer looking) 147 / 156
Teledials 147 / 156
Later Multi spokes (Shaper edges – fit over 330 brakes) 147 / 156
Teledials are prone to being kerbed and like most alloys, the rear wheels get a hard time from stones flung at them from the front wheels. This chips the laquer, allows watter to get in and causes bubling.
Then I believe they started offering the gorgeous 18” jet fin style GTA wheels off the GT on the very last 147’s.
Miscellaneous
Both cars have unique wings and quarter panels as well as bumpers, body kit etc.... I'm sure you knew that.
No rubbing strips so look for parking dings.
Red cars......Rosso 130.......They're a bit of a headache in my opinion. Look fantastic but the paint fades to pink and it doesn't fade evenly. Plastic panels fade a different colour, probably due to the plasticiser in the paint, but either way pink cars cannot be polished back to red because Alfa in their infinite wisdom, lacquered them. The only cure is a full body re-spray.
The legs supporting the lower trailing edge of the bumpers:
http://i46tobucket/albums/f112/monkeyrabit/IMG_1293g
They are the only known rust point but they are cheap and easy to replace. Its becoming an issue on pre 2000 cars. Shouldn't really be an issue with GTA's.
Sumps / Undertrays - The GTA is better than the rest of the range (in that its more stiffly suspended) but in un-caring hands it could have had its sump and undertray spanked on the tarmac, speed cushions...
Oiled Air Filters - The aftermarket K&N kind are not recommended. They are widely regarded as being detrimental to the life expectancy of the Air flow meter.
*EDIT: I bought a K&N filter for a GTA Xmas 2007. Turns out they are no longer oiled, instead they come with a very fine mesh sock that you place over the filter. Having said that, the filter is positioned very low down, where the airbox would be, making it vulnerable to deep puddles - Water sucked into engine = complete and total carnage.
Spark Plugs - As you'd expect are a pain to get at on the rear bank. would recommend they are replaced with cambelt.
Cambelts - I did a quick bit of research on the forums and found 2 GTA cam belt failures, one at 59k and one at 49k.
