tallbutlow

hi, i have a 95 civic dx auto tranny... d16zc sohc no vtec motor. when i start the car..my idle is low..around 200 or 300 rpms. i hear a loud knocking sound coming from the motor ONLY at idle and very light acceleration, the knocking completely goes away at about 800 or 900 rpms. what could be the problem? after researching ive seen someone suggest retarding the ignition timing. ive seen one guy say he had a loose spark plug what do you suggest?

my coolant is fresh.oil was changed at jiffy lube a few weeks ago. battery has good charge. tps is set correctly. distributor cap replaced recently. spark plugs replaced recently.

i dont know how long my spark plug wires have been on the car.

havent checked valve lash

HELP

street93eg

Is it a constent clicking sound or a heavy knocking sound? See if you can adjust the idle back to normal and check the timing because you might be off a tooth on the timing belt.

doublezerohatch

Have you taken the valve cover off and looked at the valves. I had this once after I adjusted my valves with a few wobbly pops in me. A nut on the valve adjuster had losened off. the rocker arm had a 1 cm gap and was knocking so bad. The knock went away around 1500 rpm.

tallbutlow

Its a constant knocking. I've tried adjusting the idle a couple times with the procedure in the manual but it never goes up.

Quick question about timing...when I shut my engine off does one of the cylinders suppose to automatically go to TDC ? I'm asking because the previous owner of the car had marks on the cam gear. When I shut my car off. They don't line up straight up or left or right.

tallbutlow

I looked at them about a week ago. Didn't notice anything out of the ordinary but I will take another look.

street93eg

Jack up the car and if you look behind the tire in the driver side there will be a little hole in the plastic on the inside of the fender which is where you can insert a socket on the crank to rotate the engine to tdc. It helps to take off the valve cover so you know when you get the engine rotated to tdc on the first cylinder all the valves on that one will be closed. Then you can check to see if the cam gear lines up with the crank pulley

tallbutlow

Sounds good..but how do you know if the cam gear is lined up with the crank pulley? Sorry I'm not very experienced with valvetrains

tallbutlow

bump

tallbutlow

i replaced this cheap a** throttle body gasket that had no cut outs (no clue why the previous owner used it)..with a OEM style throttle body gasket. that fixed my idle problem.. but my car still knocks only when in gear.. drive or reverse..in neutral or park its no knocking. when i accelerate the knocking goes away and the car runs perfectly fine with no loss in power. since it started knocking ive replaced; distributor cap, throttle body gasket, spark plugs, spark plug tube seals, oil change, IACV cleaned and new gasket, fuel filter, retarded ignition timing (maybe irrelevant but heater hoses, heater valve) any ideas???????????