had a annoying tap lately that is being rather persistant, did a oil change and it fixed the issue until recently when it returned, ran a lifter free up and its quietened it down and it eventually dissapears after about 10 mins driving or car gets to operating temperature etc. But in the last 3 weeks on cold start up (usually after car has not been started in a few days) there is a bad knocking/rattle that sounds as if its in behind the timing cover area. this sound only lasts for 1 or 2 minutes then fades and does not come back. Just curious on what it could be as if it was bearing related the sound should be there the whole time shouldnt it ? I will try to get a video and link it if that helps. I searched a little on this and found a few posts relating to a low viscosity oil relating to a knock which stopped when they changed to a more viscous oil ?
Get some lifter free up and tune Hey ProckyZ89 Grab a bottle of lifter free up and tune! Add to oil. Not harmful to your motor in any way. Originally I had looked at viscosity as a potential cause as well. Will only really work if its a carbon based problem, which is what it sounds like (worse when left to sit/ only happens on startup) Sure gets rid of carbon based knocks! Really is Magic snake oil stuff ! Well worth trying if you ask me. Your problem will dissolve before your eyes unless its major and needs servicing.
Thing is, i have a valve tap, which goes and comes and i have ran a lifter free up through the system already (mind you only used 2/3 a bottle). It worked for a while but now i have this other knocking/tapping sound on startup when cold which lasts for about a minute... its rather un nerving to be honest as i was getting ready for some major work and now am threatting it could be a bit of internal repair.
Other than potentially killing it completely... By the sound of the description, if you are sure it is a different noise than lifter tick. I would suggest an oil sample analysis, con-rod bearings are known to make noise on start up when they are worn. Prematurely worn con-rod bearings a very common in the VG.
i see.. oil sample analysis ? can anyone generally do this ? if so ill look into it ASAP as anything in relation to worn engine internals i want to jump on before it becomes a big big problem.
You said it was lifter related so I have faith in your assessment a2zed - your a good forumite, so don't be a dck and it could be anything yet. ProckyZ I didn't read your first sentence you had tried it already - my err,soz As the bottle says :"It is designed as a test" "If it keeps knocking it means it needs repairing" It is only designed to remove carbon. So theres no point continuing using it as a2zed suggests you would. Generally most people hear what they call lifter noise are generally right. So I am confident that you are right. Given that the noise has gotten worse however, it is likely the problem has compounded as well. Saying anything is speculative at this stage It can be difficult to define noises by words so the video would be a great help to all. Some motors are heavily reliant on specific viscosity to ensure the oil in the motor circulates properly and effectively throughout all the journals, in effect you only need one journel/ channel not to be lubricated properly and you can have noise as a result. Changing viscosity can fix this if the wrong rated oil is being used. If your using 10W as your precursor on your oil then your fine in general. Was the oil pump showing pressure on the gauge? What oil rating are you using and is it synthetic? You can try this in the mean time as well if you like - Pull your spark plugs out and connect a hose to a funnel, have someone turn the motor over slowly and you should be able to hear the sound amplified enough to feel and hear where it is coming from and what type of sound it is. Feel for any resistance at any point. This should help you get a good idea. Check the cylinder pressures while your at it - this will show up any major valve problems while your at it. You sounded confident it was lifter related so I think it will be in the the top where you said. Doing the above will help narrow it down. Regards (Misszens other half)
Pull your head in. Anyone who recommends magical snake oil engine flush treatments has no place under the bonnet. But having seen inside more engines than you have had hot dinners, what would I know? Procky, your local autoparts stores will be able to help you out with an oil analysis.
I'll put my 2 cents in. I'd suggest it could be VTC cam gear rattle. especially since the sound seems to be coming from timing covers. just a thought.
Oil sampling works in two ways. Firstly the oil sample will be analysed for contamination produce by the wear of component within engine and contamination from external source (Fuel, coolant, dust etc). If there is significant amount of contamination the company testing your oil should alert you immediately. The second reason for conducting oil sampling is to establish a base line of the health of your engine and alert you of component wear early by flow up testing. Depend on who does the test and how much information they have on the engine design, some can even tell you which component is failing.
