2 Years of engine pinking noise...
Ok, so I've had this 'pinking' noise for just under 2 years now. here's the history of what was done and when it roughly started to make the noise...
car had been garaged for a year or two prior to Feb 2011,
Clutch & slave cylinder replaced 18/02/11
8x spark plugs replaced, along with a service on 07/04/11
Exhaust flexi downpipe replaced a week later as there was a hole blowing in flexi section a short while after spark plugs replaced.
Now, i think the 'pinking' noise started after i replaced the down pipe, but i cant be sure, i thought i noticed it after the clutch & slave cylinder was done nearly 2 months before...
May/June 2011 i learnt off here that my thermostat was opening too early, and the car had been running at 60-75degC since me and my father owned the car before me.
I went back to my work on the exhaust as there was a few exhaust leaks, then i found the manifold support bracket that attaches to the engine block was cracked and in two pieces, got it welded, re-fitted.
Noise still there after a year, and Oct/Nov 2012 i decided to take the manifold off and inspect/ replace the 3 ply metal gasket as i thought the cracked manifold bracket had put stress on the manifold flange, also thought the manifold itself was cracked on a pipe branch, causing a leak.
I replaced the 3 ply metal gasket and i did a naff job on torquing the bolts up as the studs came out with the bolts, and i had to lock 2 bolts together on one of the studs. the manifold bolts were torqued up with the studs still on, plus i did this with the air-con compressor support bracket in the way, so the end bolt wasn't torqued properly. but i made a huge mistake as i left the dipstick tube off when i refitted the manifold, so i had to bend the dipstick tube to fit back in, resulting in false oil level readings...
Yesterday i wanted to get to the bottom of this 'pinking' noise and fix my tatty job i did, so with the help of some new and shiny air tools, i removed the air-con compressor bracket, removed the manifold, inspected, fitted new 3 ply metal gasket, fitted new oil dipstick tube, and put new exhaust manifold studs & bolts in, fitted original manifold, which was ok, and torqued up the manifold bolts to proper torque with a new and shiny calibrated torque wrench.
Took me 6 hours to do this, and i took my sweet time to make sure it went smoothly.
and did i cure the noise?.... i don't think i did, the blowing noise had gone, and responds to accelerator at idle noticeably more quickly, before i revved from idle and it took a moment to revv, now its more instant, but there is a rattle at 2000-2500rpm still.
But on inspection of the exhaust valves when the manifold was off, it looked grey, which i am not sure weather the engine is running too lean causing the pinking noise.
The 'pinking' noise is only apparent under load, you cant hear it on over run, free revving.
I have been using Shell fuel since i had the car, and have now switched to Tesco 99 RON momentum, is this Esso?
oil changed every 6 months, oil checked every 2 days
Please could any of you Alfa Guru's help me as after 2 years of this noise its getting to the point where i don't look forward to driving her anymore
Last edited by Chris_gta; 28-08-13 at 17:47.