just changed my spark plugs now engine makes a weird noise

[s13-t]

stock s13 sr20det blacktop in a 1990 240sx. changed the spark plugs today. the ones i used were ngk BKR6. the old plugs were worn with grey corrosion on the tips. anyways i torqed them to 20 lb. started fine but the engine makes a deeper exhaust sound that seems to be a thumping pattern that fallows one cylinder. the thumping sound seems to be coming from the back. when i slowly reved the motor a ticking/tapping sound fallowed the rpms and sounded like it was coming from cylinder 4. the tapping started imediatly after idle and i didnt rev past 2,000 but the tapping deffinatly stayed with the rpm of the motor. could the spark plug itself somehow be hitting the piston? how should i go about finding the problem? any ideas of how to fix it? should i pull the plugs and check their gaps again?

please help!!!!

[BoredDSM]

No the spark plug would not hit the piston unless u shot it through the motor lol but yea no. Did you properly gap the spark plugs? Make sure all wires are plugged in?

[redtop91]

Check the gap and what heat range did you get?

[scottydog]

You may have broken a plug wire during the change. Pull each wire one by one, and see which one doesn't make it run any worse. That will be your bad one.

[s13-t]

i pulled the plugs and they were at .045 now their .032 but the sound did not go away, actually got louder and deeper in tone. i have no idea what it is but at this point im not going to really worry to much about it. in less then 2 months i planned on buying a used car and pulling my sr20det for a full build. bore it to a 86.5 and get eagle rods, cp pistons. new bearings and seals, new pumps, new cams, solid lifters, ras, new gaskets of course. then bolt on a disco potato and an apexi power fc. no idea what injectors to get.. any ideas? so basically the sound is still there so im not boosting the car at all for the next two months until i can buy a different car.

[modulation]

I think I might know...

Make sure that the ceramic part of the spark plug doesn't move freely in the metal part.

I bought some cheap plugs once (denso) and I had this strange noise almost like an exhaust leak, like a tic.

I found that one of the plug was broken such that the ceramic part would move up and down freely inside the metal part.

If all else fails I'd get new plugs and swap those in.

[s13-t]

k i will try that thanks. hope its that simple. my motor keeps having problems. turbo sounds like a deisel, motor makes power then doesnt after being ran for like 5 minutes. my dipstick kept popping out and getting oil on my manifold, i was running a breather now i have a catch can installed this morning. and randomn noises that match the rpm. think somone in japan abused it. but ya i will try new plugs i was using a heat range of 6. i will call around and try and get 7 this time

[480sx]

You need to do a compression check dude..

[scottydog]

You need to do a compression check dude..

If your dipstick is popping out you've got more than a plug problem.

[modulation]

If your dipstick is popping out you've got more than a plug problem.

Couldn't that just be a bad PCV?

[s13-t]

im purchasing a new oem pcv valve off ebay, new gaskets for the ex. manifold, a new elbow with gaskets. i will install all at the same time and change my oil looking for coolant, and do a compression test. is there any spacific way to do a compression test? i will search for it and google it but answers would be appriciated thanks

[nismoracingsx]

you do a compression test....with the compression test tool

Remove spark plug, disable spark and fuel, install tool into cylinder, crank to get your reading, i know someone will jump on this and tell you how many times you're supposed to spin the engine over, i think its like 5 or something like that.

[s13-t]

thanks, yea i found a step by step guide using nico search. this sound has constantly been getting worse. and it seems like every day the car makes less and less power. but no smoke!!! ever. im not loosing coolant. the only oil i have lost has been from the damb dipstick poping out. my turbo is fine, no shaft play and no oil in the ic piping. my vacume is at 19 at idle when the motor is warm. car cruises at 10 vac. boost at 7psi no spikes. oil pressure is at 60-70 when its cold, and 11 at idle. voltage is at 13.9 at idle. idk wtf is wrong with it

[s13-t]

BUMP for helpdid a compression test today, 154, 149, 152, 151. so the rings and valves are fine correct? but the sound got WAY worse. i cant even hear the turbo spool anymore. any rpm over idle creates this LOUD F'in rattly, noise. im parking the car for the week till i have time to inspect the valve train. but what do i need to look for? what could cause such a loud rattle but be quiet at idle? i just dont understand. should i be looking at the rockers? springs? retainers? the valves? all of them? idk. is there a thread that would help. i have seen plenty of how too threads and videos but no threads or vids showing the broken part and how to look for the problem. please help!!!

[Vegascorbin]

I would not turn that motor over again untill you pull the valve cover and check for bad things. If it looks good on the cams then pull the oil pan and check for a bad things like a rod cap loose or a spun bearing. . I think you are looking towards a Major engine malfunction SOON. Stop and rebuild it now before you throw things through the side of the block and make it unrepairable.

If the noise is getting louder and power is going down then what ever is wrong is not fixing itself and is just getting ready to blow big time.

[s13-t]

i agree. this is similar to what happened with the staock ka. loud a$$ noises then cloud of smoke similar to one seen at a motocross race. i will remove the valve cover this weekend. car is parked until then. i have acsess to a trailor and a full mechanics shop, perks of having a farmer for a father the only problem is that i have no idea what to look for. obviously tiny metal shavings are bad, and anything cracked is bad. if i can move a rocker arm with my bare hands then it needs to be replaced- i think... i can afford a few oem peices but i am no where near financially capably of a full build; at least not at the moment. i have the english version owners manuel for the austrailian 240sx s14 with the s14 sr20det and the english version of a s13 with the ca18det so these will probly help. i just feel like im in over my head. wish someone with sr20 expertise lived in my town and was willing to help for free. i guess i will dissasemble what i can and take pics and upload them here. any help or suggestions would be greatly appriciated thanks

[s13-t]

rather than making a new thread...

finally had a chance to pull my valvecover. everything looks intact. key word is LOOKS. i have no idea what to do to see what is working properly and what is not. yes i have searched and read alot!!! i put it to tdc. tried to see if i could push any of the rockers don and couldnt- thats good right? also when i was cranking the motor to tdc, i used a wrench hooked to the crank pully, i could hear air escaping. like it would build a little pressure then ssssssss air slowly escaped. isnt that a bad thing? i shouldnt be able to hear it right? but my compression test was like 149, 151, 155, 152. so my rings and valvs are good... right? oil was kinda black, but no metal shavings and no coolant. idk im very confuzzled. everything i read contradicts itself. i need some advice por favor. preferably from someone that had built an sr20 and or has vast knowledge of its internals and how they work. if there is any other info needed say so please.

[osirus74]

i hope someone figures this out cuz i just started getting the same problem today with my ka-t changed plugs and click. does it go away when you unplug the injector harness for that cylinder? its wierd cuz thats the same area my metalic click is comming from.

[s13-t]

well the sound i had was there before i changed the plugs. in late may or early june i reved to the limiter in first gear for the first time. then the engine emidiatly started making a different sound. the air filter would make a woosh sound when i reved it sounding like a big vacume. then when i would accelerate the turbo no longer made a whistle sound, instead it i made a big deisel noise like a huge exhaust leak or somthing. the deisel noise got worse and worse. then one day i pop the hood to discover my dipstick chillin like and inch and a half out and burnt oil all over the place. so i removed the breather and installed an oil catch can but have yet to replace the pcv valve. the car then would start to have dips and gaps in the powerband. somtimes it would pull, sometimes it wouldnt. i changed the plugs and the sound got worse. probly just a coincidence. finally the deisel noise got so loud i couldnt hear the turbo or my bov and i was noticing major power loss and mpg loss. heres what i know: i have very little smoke, only when i would rev it hard and a little puff of white would come out but not under acceleration or anything. my oil didnt have metal shavings in it. im not burning oil or coolant. none over the plugs showed signes of detonation. my rockers and springs seem intact and sturdy. the oil i was using was mobil one fully synthetic 10w30 and came out a little black. im a noob when it comes to engine internals. idk wtf im doing. please help.

[robertftw]

with 11psi oil pressure and a possible knocking noise that probly gets loader and faster when reving it, I would say that the motor is on its way out, but also when the motor is running put your hand on the back of the altenator and see if you feel a vibration that matchs the noise, I've had to altenators go that sounded like the motor knocking. If not i would find a mechanic to check it out. It might just need bearings. as far as plugs go ngk8's are what I've run for 2 years now gapped between 28-32, iirc thats what the fsm says, I hope this helps some.

[s13-t]

the alternater has less than a thousand miles on it. and the car is dasabled for the time being, partially taken apart, so i cant start it. My plan is to replace the pcv valve, instal a new fuel pump- im still on the stock one...- and dissasemble the exhaust, and turbo looking for blown gaskets that could make the disel noise under acceleration. replace the gaskets if needed or do it anyway idk. put it all back together. if the noise is still there then i will try and get an sr20 mechanic out to my farmto look at it. if all else fails i guess i could do a full engine build.

[robertftw]

pcv valve, fuel pump, exhaust will have nothing to do with what you are telling us is the problem, just because something is new doesn't mean it's good. your oil pressure is the main concern right now, please listen to me before you waste your money.

[480sx]

The noise that your engine is making is telling you that something serious is most likely going to happen. It sounds like rod knock to me.

You NEED a full rebuild. You can do an OEM rebuild with ACL bearings, OEM rings, valve seals, and all the needed machining for between 400-700 bucks depending on who does the work.

[s13-t]

i would do the work myself. however i dont believe it to be a rod knock or a bearing going out because there isnt a knock. i have listened to almost every singly "sr20det knock" video on youtube. my engine has never made a loud knock like what i hear on the videos. damn thing just sounds like a deisel engine and has a really sketchy power band. im not ruling out a rod knock or a spun bearing i just want to get all the cheaper stuff, that i needed to do anyway, out of the way. i will see if i can borrow sombodys video camera and post a video on youtube of the sound. let me clarify on when and where the sound comes from. with the car parked, me looking under the hood, the engine at idle, no knock. valvetrain sounds a lil sketchy comes from the back. when i rev the motor in nuetral the noise isnt there. it sounds fine. no diesel noise. the horrible sound i hear is only when the engine is in gear and im accelerating. the sketchy power band- i have read that a bad pcv can cause the system to not ventilate well and make dips in the power. and i know my pcv valve is bad. maby im in denile about the engines problem but at the same time out of all the stuff i have read it just doesnt seem like a rod or a spun bearing. idk...

[redtop91]

i put it to tdc. tried to see if i could push any of the rockers don and couldnt- thats good right?

Yes. At TDC the motor is at the top of it's compression stroke and all the valves are closed. The Rockers enact the valves to open so if you could push them down you would have compression issues.

also when i was cranking the motor to tdc, i used a wrench hooked to the crank pully, i could hear air escaping. like it would build a little pressure then ssssssss air slowly escaped. isnt that a bad thing? i shouldnt be able to hear it right? but my compression test was like 149, 151, 155, 152. so my rings and valvs are good... right?

Think about it for a second. When you are cranking the motor you are compressing the air. When you finish the compression stroke, the exhaust stroke begins and the compressed air is escaping the cylinders through the exhaust valves. When you take an air compressor and spray releasing the compressed air it makes a hissing noise. If your engine didn't make this noise that would mean trouble. If your compression check read those numbers that portion of your engine is healthy and it's time to move onto other things. It's sounding like your head was starved of oil and your lifters are ticking. If you could get a video that would help. Here's a video of my lifters ticking:

[s13-t]

thats wat my head souns like. then when i accelerate the car has a big burly tone like a truck or sumthin. that y im assuming axaust and i need new gaskets.

k assuming that it is my lifters does that mean that i HAVE to bleed them asap? will a dry lifter cause damage? also do i need a new oil pump? strainer ect... no dents on the oil pan. pan is brand new. although i dont have an underskirt for the engine bay... somthing could have bounced up? i will check to make sure.

thanks for the imput guysi will have an update on the car probly late friday or early on saturday

[nismoracingsx]

the horrible sound i hear is only when the engine is in gear and im accelerating.

anybody else see something wrong here? He only has noises when he's in gear...and everybody is telling him he has massive engine problems....loose/damaged flywheel can sound like knocking/rod knocking.

[s13-t]

yea see i was wondering if it was my clutch cause some times its hard to shift. ok well more info on the sound. it sounds like a lawn mower when im accelerating. like a have a big a$$ hole in my exhaust or somthing. then there is also lifter tick like the video. i havnt been able to go out and work on it yet. finals week

[redtop91]

k assuming that it is my lifters does that mean that i HAVE to bleed them asap?

No but ticking lifters is the most annoying sound on this side of rod knock. You'll want to shoot yourself after a couple of weeks.

will a dry lifter cause damage?

A dry lifter would because it would have no method of checking the rockers as the hydraulic pressure adjusts the valvetrain automatically. Hydraulic lifters suck, Lessens maintenance though. A dry lifter would be something that happens after you throw a rod. That being said, if in fact your lifters need to be bled that most likely means your head was being starved of oil because either A. Oil was low or B. Low oil pressure. Find out which and hope nothing happened to your bottom end. FWIW, on my SR rod knock shortly followed ticking lifters. Not necessarily what has to happen to yours just take the standard precautionary steps.

also do i need a new oil pump?

Only way to know that is with an oil pressure gauge. At a warmed up idle a healthy pump will see around 23-25 psi.

strainer ect...

Nah. It's always better to address the issue with what you have (Unless you find your pump is bad or something) than to buy stuff to try and fix it because it usually doesn't help unless you know exactly where the problem is.

[s13-t]

my oil pressure gauge when warmed up, reads 11psi at idle.... but my dipstick never showed signes of low oil...