Tapping sound?

[j cAT]

Originally Posted by mike561

The air filter is clean, the car used to shoot out black soot when i first got it but hasnt in a while now

because it was running poorly creating carbon deposits when first purchased and the oil is now black replace oil and filter and add 5oz of marvel mystrey oil. when it turns black again,,, repeat... eventually the engine will get cleaner so that your noise will stop... if not then at least the engine will be cleaner to replace any worn lifters/cam componets.....

i wouldn't replace just the lifters/cam without cleaning the entire engine of that carbon ,as carbon can rapidly wear an engine.......

[mike561]

Yeah ive been waiting to use the mystery oil, ill add it in the next change

[j cAT]

Originally Posted by mike561

Yeah ive been waiting to use the mystery oil, ill add it in the next change

if you are driving this vehicle often, you should not wait to replace this black carboned engine oil....


I would cut open the oil filter and see how much debris is in the filter media , and upon removal of filter media if i could see light pass thru it... also do not use fram oil filters........a/c, purolator pure one, wix these are good....

[mike561]

ok, yeah the oil has been changed three times so far since i had the car

[j cAT]

Originally Posted by mike561

ok, yeah the oil has been changed three times so far since i had the car

how many miles does the oil take to turn black ?

how many miles do you go on the oil change ?

[mike561]

I do the usual every 3k mile change, i havent wached it though

[GreyGoose006]

mine looks like black ink when i take it out and after a few miles of driving on new oil, it looks brown.
this engine is pretty much worthless though, so im not too worried about it.

its a 3.8, so, meh...
i usually do 2k oil intervals for the fact that if i go longer, i wont be able to see though the oil.

[mike561]

I think ill just change it next week even though its not at 3k yet, ill add that mystery oil in too. i was listening to it again tonight, and its a slight tap, but its not very loud or anything

[j cAT]

Originally Posted by mike561

I think ill just change it next week even though its not at 3k yet, ill add that mystery oil in too. i was listening to it again tonight, and its a slight tap, but its not very loud or anything

I would get a vacuum guage and check for any vac. leaks.... also at idle vac should be high and steady at 21inches.... if lower/or jumping something is wrong.... if this is 21inches and steady this is when you would adjust the mixture screws. has the mixture screws on carb been drilled out ? if so some one adjusted the mixture..


this is usually done because the engine has vac. leaks which effect idle and rather than repair vac leak these screws are adjusted .. this then causes a rich mixture..which may be your problem.....


another cause would be worn engine componets like piston rings,and excessive oil entering the combustion chamber...how much oil does this consume in 3,000mi ? if it uses 2quarts or more, then you most likely need engine work...

the vacuum gauge is a great tool to determine engine condition....as vacuum readings will narrow done whats bad inside....before buy vehicles like this it is wise to use this to determine if engine is good...

[mike561]

May sound like a dumb question, but where would i plug a vacuum guage too? also another issue ive been having, i notice sometimes when im at a complete stop, then go to step on the gas it sounds like the engine cuts of for a split second, and i'll feel a loss of power too...

[j cAT]

Originally Posted by mike561

May sound like a dumb question, but where would i plug a vacuum guage too? also another issue ive been having, i notice sometimes when im at a complete stop, then go to step on the gas it sounds like the engine cuts of for a split second, and i'll feel a loss of power too...

mounted on the intake manifold are vacuum lines... buy/get a T adapter and insert vacuum gauge on vac line to air cleaner or vacuum line from manifold to hvac vacuum ball, connect T close to manifold for accurate readings as the line you connect to may have a leak ...your engine should have many vacuum lines 5/32 sized id ...to be sure there is no leak on the line you tapped into firmly pinch the line leading to device and if vacuum increases that line/device has a leak...21 inches and steady is good ....

[mike561]

ok, anyone know about the power loss issue i mentioned above too?

[j cAT]

Originally Posted by mike561

ok, anyone know about the power loss issue i mentioned above too?

this hesitation is usually a vacuum leak....also if you find that there are vacuum leaks and someone adjusted the carb mixtures you will have to re adjust the carb mixtures....


the other thing could be timing is too retarded....

your engine should idle in gear at 500rpm so smooth you can't tell is running... when you take foot off the brake vehicle should almost not even roll forward on level surface...if you have vacuum leaks rpm has to be increased so that engine runs smoother and does not stall, and hesitate..

[mike561]

It does run smooth after about 5 min of a cold start, if i stomp on the gas a few times the idle will eventually knock down and become quiet. ill have it checked for vac leaks though, sound like thats what it is, i wouldnt be surprised. whats involved in fixing vac leaks? new rubber lines?

[j cAT]

Originally Posted by mike561

It does run smooth after about 5 min of a cold start, if i stomp on the gas a few times the idle will eventually knock down and become quiet. ill have it checked for vac leaks though, sound like thats what it is, i wouldnt be surprised. whats involved in fixing vac leaks? new rubber lines?

mounted on the intake manifold are vacuum lines... buy/get a T adapter and insert vacuum gauge on vac line to air cleaner or vacuum line from manifold to hvac vacuum ball, connect T close to manifold for accurate readings as the line you connect to may have a leak ...your engine should have many vacuum lines 5/32 sized id ...to be sure there is no leak on the line you tapped into firmly pinch the line leading to device and if vacuum increases that line/device has a leak...21 inches and steady is good ....go from line to line repeating this pinching proceedure until all leaks are repaired.... you may need several feet of vacuum/gas line hoses also any line cracked just replace....base of carb lines get brittle poor seal replace etc...