Alfa Romeo Forum banner

1 - 5 of 5 Posts

·
Registered
Joined
·
8 Posts
Discussion Starter #1
Hey all. Thought the following might be of interest/help to someone at some time.
Recently bought another 147 in fabulous condition, 2009 5-door 2 litre TS 5 speed manual with 80,000Km, previously owned by an old chap who was fastidious with it.

933867


On the 250 mile trip home I was quite certain that this like new car was seriously down on performance compared to our 2003 model - similar specs except 3 door.
Acceleration was greatly lacking in enthusiasm but things improved as the revs gradually built up.
When Sue - yes that's Sue - began using it around town, a number of scary things began to happen.
When accelerating briskly to get into traffic, the car would slow suddenly, almost as if you had applied brakes, regardless of the accelerator pedal still being at say half travel.
A number of faults began appearing on the dash - traction control, ABS/VDC failure, ECU failure, audible alerts and a red hazard light.
Car would still drive on low throttle settings, although would do the same thing again if revs reached around 3500rpm.
After a couple of stop and start cycles everything would return to normal and all the fault lights would gradually turn themselves off.
Problem would return when the car got hot and a fair bit of pedal was in use.

I bought a Fiat/Alfa OBD scanner from Amazon, an iCarsoft i950, and it arrived 2 weeks later.
It was very easy to operate and I found 3 fault codes logged up. I do not have the codes now, but the faults were - accelerator pedal position sensor faulty/MAF sensor faulty/accelerator pedal position sensor wiring fault circuit B.
I figured 'circuit B' meant in the engine bay as I had read of people with a 'circuit A' fault being a connector behind the glovebox on some models.
I decided to clean the multi-pin connector at the throttle body, as it was the only connector I could find in that circuit without removing the accelerator pedal assembly.

Now - the nice old previous owner had recently had the cambelt and water pump etc changed, new 'cups' (?) fitted in the gearlever mechanism which had firmed the lever up nicely, and the muffler mounts repaired.
He seemed to think the outfit who did the work were pretty good, although he chose to supply the cambelt kit himself and thus save about $500.
They were not Alfa people and I was wondering if they could have stuffed anything up in the process of doing the work.
So - I'm looking under the bonnet and I notice that a felt cover over the inner guard has not been fastened properly. Actually, not at all on one end, even though the screw was in place and quite tight.
Always indicates to me a lack of attention to detail on behalf of anyone who may have been working under the bonnet before me.
So I pulled it out at the rear edge to refit it as it should have been, and found that it had been totally covering the engine air intake.!
Well, that's not going to be helpful I thought...

933869


And then I thought - wait a minute - that is the entire problem.!
The throttle body sensor versus the airflow sensor will not be making sense, so the fault codes are all pointing to a problem in that area - which I might add - is about as accurate as most fault codes manage to get very often.
I refitted the cover and took the car for a drive. Transformed.! Goes like a rocket, no hesitation, no problem with red lining it, no more fault lights.
I then discovered that the muffler mounts had broken again because someone had just wrapped cable ties around the separated rubber supports.
I am beginning to think that the workmanship has been very poorly managed, and I will now remove the covers and see if the cambelt really has been replaced, as I no longer trust them at all.

However - I thought it worth passing on that even the scariest fault indications can have a very simple cause, so just look around before you rip it all to bits.
Obviously the ECU/ABS/Traction control alarms were simply kneejerks because the electronics could not decide what the hell was happening.
It would seem that an air restriction - like a blocked airfilter - may not be a part of the program...

Love my Alfas.. :)
Kilroy
 

·
Registered
Joined
·
8 Posts
Discussion Starter #2
Oh.
This is how the cover was when I noticed it..

933872



Now a happy 2 Alfa family..

933873
 

·
Registered
Joined
·
2,602 Posts
With the wide range of faults I would check the battery/connections and earth points aswell as the faults all point towards issues usually seen with battery/earth problems
 

·
Registered
Joined
·
8 Posts
Discussion Starter #5
There have been no more faults of any kind since I refitted the loose cover, so it would seem that they were all generated by the blocked air intake. Onboard diagnostics are still an imperfect science...
 
1 - 5 of 5 Posts
Top