Technical Whining metallic knocking noise coming from engine when accelerating

[Krepatis]

Good day All.
I'm getting a whining knocking metallic grinding sound when I accelerate.
The Engine warning light has come on but has since gone out.
I've had the car engine management system diagnosed but it hasn't got a fault code logged.
My car has had a full service with no mechanical problems found.

Could it be the Transmission / Drive Gears going?

An RPM Sensor?

Any help greatly appreciated.

Krepatis.

 

[gadge]

Hi krepatis just out of curiosity how many gears does your bravo have?

 

[Krepatis]

It's the 1.4 Dynamic 2008, 6 Gears.

 

[Krepatis]

Also to add.
It's had a new clutch and CAT Converter fitted in the last few months.
However since the CAT was fitted this fault has arisen. Might be a coincidence. Also noticing I'm using a hell of a lot of fuel. Consumption is high right now.

 

[gadge]

The six speed gearbox is the imfamous M32 box which has a terrible reputation for poor reliability but there are tell tale signs such as the gear stick moving as you accelerate or the whining only happening in 5th and 6th. I'ld say at the moment it's probably not the gearbox as that wouldn't throw and engine light on. How does the car drive?

 

[Krepatis]

Hi Gadge.
The car drives fine, apart from noticing higher fuel consumption.The gears and steering are responsive are slick moving through the box etc. Acceleration is okay,it's this whining grinding metallic noise that sounds bad.The Engine management symbol had come on then off with the dashboard message "Check Engine" etc. But like I said when diagnosed no fault codes were logged.I'm loathed to go to my local Fiat dealership as I know they charge the earth for diagnostics. Quoted me £114 for purely a diagnostic check!!! No bloody chance.

 

[g8rpi]

Hi Gadge.
The car drives fine, apart from noticing higher fuel consumption.The gears and steering are responsive are slick moving through the box etc. Acceleration is okay,it's this whining grinding metallic noise that sounds bad.The Engine management symbol had come on then off with the dashboard message "Check Engine" etc. But like I said when diagnosed no fault codes were logged.I'm loathed to go to my local Fiat dealership as I know they charge the earth for diagnostics. Quoted me £114 for purely a diagnostic check!!! No bloody chance.

If the light has been on there should be stored fault codes. It does however require Fiat specifc equipment / software to read them. It sounds like your garage does not have the correct diagnostic equipment. The popular choice here for DIY is Multiecuscan (MES) If you have a windows laptop a full set of interface, adaptors and software is less than £100. Were are you located? Maybe someone on here can run MES for you.
Sounds like you ave an engine issue and it seems lkely that it is connected in some way to the work that has been carried out. There may be more than one problem.

Robert G8RPI.

 

[Krepatis]

Thanks G8RPI
I agree there's a problem the diagnostic check initially was done by my local Quik Fit then an independent garage.Both drew a blank with regards to an error code.
My location is Watford, Hertfordshire.So if anyone has the software to do a check and are in my area, I'd be greatful for the advise etc.

Regards
Krepatis

 

[dtimmins1985]

Thanks G8RPI
I agree there's a problem the diagnostic check initially was done by my local Quik Fit then an independent garage.Both drew a blank with regards to an error code.
My location is Watford, Hertfordshire.So if anyone has the software to do a check and are in my area, I'd be greatful for the advise etc.

Regards
Krepatis

You said you have just had your cat replaced and have increased fuel consumption and a metallic banging noise.

Have you checked the exhaust system to make sure there are no leaks, that would explain the high fuel consumption.

Also check the lambda sensors (before and after the cat) these can throw up the check engine light (happened on my old stilo).

Also, check that they have actually fitted them correctly and check all mountings for exhaust around the gearbox area, also check the gearbox stabiliser mount (it stops the engine and gearbox from rocking under load, this caused my manicat to snap 3 times!! until the garage noticed it was the mount that was shot causing the engine to rock, i launched it one day and then BAAAARRRRRRR loud as feck exhaust and check engine light came on) then i could hear knocking etc as the mount was shot.

 

[Krepatis]

Thanks DT.
I'll make a note of this and get the garage to check it out.

Regards
Krepatis

 

[850kd]

Take a look at the aluminium heatshield on the manifold downpipe. The fixings corrode (and come loose) and give rise to a few mysterious noises. Especially noticeable on startup but evident when idling.

 

[alexfagg46]

The six speed gearbox is the imfamous M32 box which has a terrible reputation for poor reliability but there are tell tale signs such as the gear stick moving as you accelerate or the whining only happening in 5th and 6th. I'ld say at the moment it's probably not the gearbox as that wouldn't throw and engine light on. How does the car drive?

Hi my gear stick moves when I come off and on the accelerator only when I’m in 5th gear in my 1.2 Grande Punto. Engine management light flashed on other day but haven’t seen it since and now I seem to have a noise when accelerating a ‘shhhh’ noise or a hiss maybe, car seems less powerful also can you help at all?

 

[gadge]

Hi my gear stick moves when I come off and on the accelerator only when I’m in 5th gear in my 1.2 Grande Punto. Engine management light flashed on other day but haven’t seen it since and now I seem to have a noise when accelerating a ‘shhhh’ noise or a hiss maybe, car seems less powerful also can you help at all?

Hi Alex your much better off asking this question in the Grand Punto section as this may well be a familiar problem to those guys. The moving gearstick issues tends to be a problem with the six speed M32 gearbox as fitted to the bigger engined cars. The hissing/shhhhh noise doesn't really sound to me like a gearbox fault but more an induction problem.

 

[alexfagg46]

Hi Alex your much better off asking this question in the Grand Punto section as this may well be a familiar problem to those guys. The moving gearstick issues tends to be a problem with the six speed M32 gearbox as fitted to the bigger engined cars. The hissing/shhhhh noise doesn't really sound to me like a gearbox fault but more an induction problem.

Thank you
Can I just ask what you mean by an induction problem
I am new here as you can see

 

[gadge]

Thank you
Can I just ask what you mean by an induction problem
I am new here as you can see

Of course, sorry, in basic terms the Pistons in the engine sucks air and fuel into a cylinder where it's compressed then ignited which drives the piston down creating power (in the case of a petrol engine. A diesel works very similarly but doesn't ignite) so the engine is kind of like a giant compressor, sucking air (and fuel) in and blowing burnt gases out. Induction is usually the term used for the "sucking" part of the prosess, so anything from the air filter box right through to the cylinder head is induction. So a hissing or whooshing noise could be the sound of air escaping from somewhere and with less air going into the engine you get less power as you need the oxygen in the cylinder to give a greater detonation when mixed with the fuel.

The problem could be something simple like perhaps the air intake hose has a split or has become detactched from the air box or airflow sensor so the fuel that's being injected into the engine isn't the right ratio so the power becomes effected. Like I say the guys in the Grande punto section may know exactly what the problem is

 

[alexfagg46]

Ok thank you very much