When the oil is at temperature, the oil is at an acceptable level, i.e. there is the 'low' mark, the 'top' mark and above the top mark 'x' its halfway between 'top' and 'x' (apparently once it reaches this you change the oil). I have run the engine and firstly, the tapping is only really audible when the car is under load and not when idling. Sometimes its louder than other times and this can happen instantly. The sound of tapping sounds more like 'pinking' when outside the car. When I ran the car as you asked you could hear the tapping but much fainter than when under load. Hope this is not too confusing. Thanks, Milo
Ok. Thanks, Milo.
Hello, I don't mind waiting another day or two, but no longer.Thanks, Milo.
Hi Mike, just reading your message now. I didn't talk to the technician directly, but the secretary who read it off the sheet. I must clarify as it actually says the 'vacuum pump' is where it was coming from. It sounds like a tapping from inside the car and bad 'pinking' from outside. I have been under the bonnet with the plastic cover off the top of the engine and with someone gently revving the engine, it sounds to me it is coming from the top of the engine. The car has 85,000 miles. No smoke ever coming from the exhaust. (I had changed the oil and filter last year and my motor factor gave me what I was told was the right spec 5w30 AECA A1/B1. The DPF light was flashing far a while recently and then the engine management light came on and it went into limp mode. When I brought I to the dealer he said it was a built up of soot and did a forced regen. All ok then, but he didn't question the oil. I found out later that it should only be 5W30 AECA C1 only as this is low ash oil specifically for the DPF. Just changed to this oil don't know whether this would make any difference?
Driving today, it seems that if the car is driven gently, there is little or no tapping, if its driven hard, the same, but I does make the noise when driven normally??.
Hope this helps. Milo.
Did you receive my last email on 08/09? If so, any ideas??
Hi Mike. Thanks for the reply. Somehow I don't think it's the valves. The noise seems nonexistent at idle and when driven hard! Its seems to be getting worse like bad pinking. I'd like to know what the vacuum pump is used for and why it would be tapping/rattling? (according to the Mazda technician). I read on an online forum that vacuum pump is oil pressure fed from a port in the centre of camshaft. Sometimes the injector washers leak and blow carbon into the rocker box.
Carbon gets washed down and picked up blocking the oil strainer.
The sump should be dropped and the strainer should be cleaned every 40k miles! maybe I'll try this? Milo.
Thanks for that Mike.
I was always under the impression (or was told by a dealer) that modern cars didn't 'pink" anymore as the ecu etc. Anyway, now you have explained the vacuum pump, it's purpose and how it goes wrong it makes more sense, (I have noticed that the ABS when driving on the motorway is more 'pronounced' recently, ie rather than a gentle oscillating feeling in the break pedal when applied, it feels more like there is a slight buckle in the wheel/s (even though there is not). Also, the engine has started to 'hunt' at idle, i.e. it drops revs for a second or two and then goes back to normal for about 4 seconds and repeats...
It would be great to do the test with the screw driver you mentioned, but the 'pinking/rattling' sound only really happens when you are driving (i.e. have the engine under load) and not all the way through the revs either). I'll try to get someone to gently rev the car and see if I can get the noise to happen and try the test.This is really frustrating! Thanks again, Mike.
By the way, Mike, Iam new to this site. I have given (maybe prematurely) a good rating (would like to give higher), I assume that this means you will get paid etc, is there anything else I need to do?