Hello Everyone
Sorry for my first post being a question I have recently aquired a 1.6 Stilo for the other half her 145 has terminal rust
It's generally a good car but had a broken exhaust flexi which we tried to get replaced today but have been told the back engine mount (sort of looks like a tennis racket) was shot and needs to be replaced before they would fit an exhaust. Does this mount fail? Or am I being strung a line?
Also it seems that the motor has a very small misfire at idle which I didn't notice on the test drive Could this just be the exhaust leak messing with lambda readings. It shows no faults on the dashboard at all but will ecuscan show any?
Don't know too much about fiat engines how similar are they to the Alfa ts obviously 4 plugs less but any similarities?

Thanks

Mark

Welcome to the forum Mark

From memory I've read other poples threads where they've said the idle speed is a little low making the engine feel a little shakey, could be that? The "back engine mount" they're talking about sounds more like the gearbox mount to the subframe. Heard of them failing on MK2 Puntos and if it's failed it could put extra strain on the flexi as the engine/ gearbox may be able to move backwards and forwards a little more if the mount was worn. Is there any clunking sound when you pull away from a standstill?

If there's no fault codes then clean the spark plugs and clean the throttle body and see if that makes any difference

Hi
Thanks for the welcome
To answer your questions rev counter needle doesn't fluctuate but it just feels that it misses on a cylinder every few cycles
There a now clunks or knocks at all
Will try to get it connected to laptop tomorrow to see if there are any fault codes logged.

Could just be your sparks needing a bit of wire brush treatment. If you jack the car up on the nearside and look underneather you'll see the gearbox mount, I think the circular end is the part bolted to the subframe. Take note of any fault codes you have and then clear them, if any come back up then you can compare what you have noted down previously.

The mount should be quite straightforward to remove youself:



A couple of bolts, one on the chassis and one connecting it to the bracket on the gearbox

Should be cheap to buy as well and if you can fit it yourself then you're laughing. Exhuast flexis are easy and cheap to replace, the garage should be able to cut the old one out and weld in another in its place, £40 or so.

It's become known to me that 1.6 engine is not the smoothest running at idle. Mine also has a little pop every now and then, but passed the emissions test for it's MOT and doesn't really cause any problems when driving.

While you're at it, give the MAP sensor a clean with contact cleaner too. It's only 2 screws and worth a try. When I bought my car, MAP sensor was gunky and general running improved once it was cleaned up.

I think the exhaust shop deserves some credit for being proactive enough to look for the cause of the flex joint failure. The flex joints seldom fail for no reason so I think it's quite likely that one or more engine mounts are compromised. I think there should also be a bracket securing the exhaust pipe to the sump (between engine and gearbox) so have them check that, too. On the Alfa 156 a bracket on the front of the engine (securing the down pipe) was always cracked and quite often missing.

It's true that an exhaust leak can mess up the idle.

Speaking of Alfa, I know that the 1.8 FIAT engine and even the 2.4 bears more than a passing resemblance to the Alfa Twinspark. They both have a very similar design for the plastic cam cover, the timing belt, variator, water pump, thermostat, and induction system. Differences are (on the Twinspark) the extra spark plugs, with coils AND HT leads, the balance shafts and belt (with weak tensioner), a more complex arrangement of the timing belt covers, and a power steering pump and reservoir that gets in the way for some operations. Also the later Alfa engines have a plastic coolant manifold under the exhaust manifold - silly, because there are also dual catalysts nearby.

Both 2.4 and Twinspark (I think 1.8 as well) have MAF sensors on the air box, prone to contamination (can be cleaned with MAF sensor cleaning spray sold by CRC) and also air leaks in the pipe work after that (to the throttle body) must be checked for. The Stilo (my 2.4) seems to have a nice tough plastic intake pipe not prone to splitting (the Alfa ones are rubber).

So generally, I think the FIAT versions are easier to maintain

I think the 1.6 FIAT engine is totally different to the others. Looks like the inlet and exhaust sides are switched over. I expect there is no variator and no variable induction system. Less to replace when it gets old Thanks to James for pointing out the MAP sensor (manifold absolute pressure), no MAF (mass air flow) sensor I presume, so you have a different and more reliable part to clean.

There were some versions of the Alfa 145/146 and 147 (Junior, I think it was called) sold with a 1.6 105bhp engine that I suspect was the FIAT engine. Other versions had a 1.6 Twinspark (120bhp) which resembles the 1.8 and 2.4 FIAT engines as described above.

Hope that clears up the differences...

-Alex

Thanks for all the info
Exhaust now fitted but engine/gearbox mount not changed as it seems incredibly tight and I did not want them snapping it and rendering the car unusable!!
James yes that's exactly the symptom in the old days you would say the engine is hunting a bit if that's what they are like then fine. The MAP sensor I assume is in the intake piping before throttle body.
Alex thanks for the info at least some of my knowledge on Alfa's will Come in handy as for the exhaust bracket on the Ts I like quite a few people remove it as it can be prone to smacking speed humps and leaving large holes in the sump

Help with FES readings

Just trying to trace this hunting problem I ran FES and found no error codes I just need confirmation of some readings namely

Pre-cat lambda fluctuating between 0.014 and 0.903
After-cat lambda between 0.039 and 0.815 this figure will drop low when the engine is revved

It's saying system lean

Do these readings seem right

Thanks

Mark

alexGS said:

I think the 1.6 FIAT engine is totally different to the others. Looks like the inlet and exhaust sides are switched over. [...] There were some versions of the Alfa 145/146 and 147 (Junior, I think it was called) sold with a 1.6 105bhp engine that I suspect was the FIAT engine. Other versions had a 1.6 Twinspark (120bhp) which resembles the 1.8 and 2.4 FIAT engines as described above.

Click to expand...

The 1.6 Fiat "Torque" engine found in the Stilo is derived from the old Lampredi SOHC, to my knowledge it has never been used in an Alfa. It's not related to the 1.6 Twin Spark engines in Alfas, which is part of the Fiat SuperFire series, which also includes the 1.8 and 2.4 engines found in the Stilo.

The difference between the 105bhp and 120bph versions of the Alfa 1.6 TwinSpark is apparently the presence of a camshaft variator on the 120bhp. I believe the 1.6 105hp was launched as a replacement for the SuperFire-based 1.4 TwinSpark used in the Alfa 145/146. This 1.4 TwinSpark was related to the 1.4 12V engine found in early versions of Fiat Bravo/Brava, but apparently this was not a good engine, as it was eventually phased out in favour of a regular 1.2 16V Fire engine in later versions of Bravo/Brava.

Re: Help with FES readings

Might sound a bit random, but is your car still hunting with air conditioning switched on? My car tends to run better as revs sit a fraction higher and overall driving experience is smoother.

Re: Help with FES readings

Spark155 said:

Just trying to trace this hunting problem I ran FES and found no error codes I just need confirmation of some readings namely

Pre-cat lambda fluctuating between 0.014 and 0.903
After-cat lambda between 0.039 and 0.815 this figure will drop low when the engine is revved

It's saying system lean

Do these readings seem right

Thanks

Mark

Click to expand...

if you dont have fault codes relating to lambdas, dont look for them... if it aint broke dont fix it!
air leaks are only important if they are before the lambda sensors. if you have a leak in the flexi i doubt this would cause a rough/unsteady idle.

what work have you carried out so far Mark?

have you tried looking at the vac hoses for leaks etc.?

Hi Rich
To be completely honest not done anything but put the diagnostics on it (no errors present) as I've had to replace the upper whishies on my 156 and try to track where the smell of petrol is coming from on it so not much time to pay with the stilo
I have had a full exhaust fitted and the hunting is still there

Ok first thing is first then buddy lets start with the free to try things.

Clean and reset your throttle body and map sensor (instructions in my sig)

check the gap on all your spark plugs (0.9mm)

check all your vacuum hoses for connection, holes and general condition

Finally, and the most unlikely if You havent had it apart, ensure all the pipework and connections downstream of the throttle body are sound. A leak here allows 'unmetered' air into the Engine messing up the fueling

the next cheapest thing that wont hurt to replace is the Engine air filter, available from a lot of places for less than a 10er and probably less than a 5er if You look hard enough... Dont go to Halfrauds... Try a proper motor factors like Euro Car Parts, GSF or Andrew Page. If You know what youre looking for Try ebay sometimes Its cheap