wtf just happened to my car??? Please help

[bsbllfit7]

ok so I was just driving my car and all of a sudden it started shaking violently when in gear. It wasn't all the time just quite often. It felt like it was missing heacily when the problem was happening. At one point I could hear backfires coming from my exhaust. I turned the car off and on and it fires right up and idles wonderfully at 700 rpms with the same amount of vac as before. I then gave it a few revs and I hear a rattling coming from the engine bay. It wasn't all the time just when it was revved up and for a certain time. Not the WHOLE time it was being revved. When it was mising on the highway the tachometer needle would jump every time. Like about 500 rpm jumps when it missed. What the hell could this be? Could it be a bad cool not sendin the signal at all times? Bad transmission? I don't understand why it would be ratteling even if it was a cool or ignition related omponent. Please help and I'll be so grateful.

 

[vzeoh6om]

is the check engine light on?

 

[dsm8883]

That sounds like a rod when u rev it real high. The more i watch the more it sounds like a rod bearing. (I) would pull the oil pan and check the rod bearings.

 

[bsbllfit7]

no check engine light and wouldnt the knock be all the time if it was rod knock? This is very very sporadic

 

[XiKeiyaZI]

Better be safe than sorry.

Bite the bullet and drop the pan.

 

[bsbllfit7]

ill go take another video for you guys so you can hear the knocking sound better. Ill do an idle and rev

the noise at idle is lifter tick. Damn those 2g lifters!

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http://www.dsmtuners.com/forums/new...ounds-like-knock-noise-coming-4-cylinder.html
could this be my problem? i had the flywheel professionally done though

im not so sure it might be a bas 1g cas??? It starts up normal drives normal tell it sees full operating temp. Then it sounds like im running on two cylinders like a wrx or something. Now if im right thats a sign of a bad cas isnt it?

 

[vzeoh6om]

he stated that he had to press in the clutch for the car to idle properly and that the knock goes away when on the throttle....it dosent sound like your symtoms but then again no two cars are the same....

 

[bsbllfit7]

i dont think its that either now, i just let it warm up again and the clutch pedal has no vibration so i dont think it would be that. Im still going crazy over this, i do think it might be my cas that is failing when hot instead of the coil packs, anyone have a test to figure out which one is the culprit?

so i went out to the car and warmed it up, let it run tell it started missing, then i pulled the plug wires from the plug, on all 4 plug wires i heard popping as the spark was sparking. That leaves me to think that its not getting fuel and that is the reason for the missing. What the hell could that be!

 

[nyTalonTsi]

Does the tach jump around like crazy when the car is warm? It's something electrical if it runs okay till warm like the cas or coil pack.

But if the tach jumps all over the place I can say its the power transistor. Had the issue last winter with my old car, wouldn't miss till the car got warm then sounded like a sick horse.

 

[bsbllfit7]

it doesnt always jump around, the tach was jumping when i was driving and it was missing badly, it would jump around about 500 rpms or more. This is really starting to bug me, as i said i took the spark plug wires out whjen i was having the problem and the plugs were all sparking.

also ill be driving and then when this happens and starts missing thats when the rattle starts again. Also when it starts missing if i let in the clutch the car rpms will go straight down to 0 and die, Then will have to restart the car. I am so so confused by this problem, there is no check engine light to tell me whats wrong and i dont have a ton of money to throw at problems right now just to find out it wasnt that,

 

[shockracer]

crankwalk? as for the miss, i would try a new set of plugs they are cheap.

 

[bsbllfit7]

how could that be crankwalk, those arent even symptoms of it . If anything it would be a spun bearing or something like that which produces rod knock, but then again it cant be that because the knocking is intermittent. I am thinking it might be transmission related because when this started happening with the knocking my girlfriend was trying to drive my car. She was struggling with first gear and accidentaly dropped the clutch at high rpms and did some crazy stuff. Still trying to figure out the misfire though! Once again does anyone have any tests to figure out if this is power transistor, coil packs, cas related? Or what the hell else this could be. Once again no CEL's have been tripped from this issue.

 

[tenn-gsx]

Did you try a new transistor? I see it mentioned several times but you ignore it. Transistor will cut fuel to 2 or 4 cylinders and it will cut the tach signal by 50% or completely if it totally cuts out.

 

[Dserge]

Damn that is a beautiful car too!!

 

[1997_GSX]

I'd just drain the oil and check for metal, its an easy and quick test. Plus your only out $25 for new Mobil 1 and a nice filter.

 

[jmorri15]

we all assuming the worst. it may not be internal at all, try taking off all the belts other then the timing belt. try and see if its something on the outside of the motor.

 

[bsbllfit7]

the transistor sounds like its the problem to me, cause its still got spark when this problem is happening, i know this because ill pull the wire while the engine is running and its still popping. It sounded as if it was fuel related and one of the posts above said it can cut fuel

ha thing is i have no clue where the transistor is on this car. Also would that be a part stocked at autozone or napa? If so about how much does it run for one. I will go get it today if they have it. If not ill need to know where its at to go to a junk yard.

 

[dsm8883]

Check one thing at a time!!!!!!!!!! Like the (knock) pull the oil pan and check the rods and mains, if the engine has a bad rod or main who cares if it is missing??? I would be checking on the noise and then worry about a random miss. If you pull the oil pan and everything is great than mark that off the list.

 

[bsbllfit7]

im thinking the noise is a collapsed lifter or failing lifter. The reason for my theory of this is that the noise is coming from the very top left side of the engine. I used a stethoscope to try to listen to where it is coming from. That might explain why the sound doesnt follow all rpms or happen at idle. also when the car has regular oil pressure this is not a problem.

 

[jimbob_843]

It could be a spun bearing. Mine only knocked when it first started and then when the rpms went up. But as long as the rpms were low it wouldnt knock, even while driving. Drain the oil and check for shavings.

 

[bsbllfit7]

alright and if the bearing is crap, should i just throw in some new bearings and call it good or would i need to do a whole tear down of the block and polish the crank and what not.

 

[boosteclipse]

If the bearings are shot don't just replace with new bearings, if there is enough play to make knock then somthing is scared. Drop your pan and check it out. Look for shavings in your oil, check any slack in rods, also check your balance shafts for play. Rod knock has a way with tricking people.

 

[bsbllfit7]

im gonna fix the problem whether it be the transistor or coil pack first, then drive it around and if it starts knocking more ill drop the pan and check things out. No reason taking it off prematurely if in the end id need to rebuild the block anyhow.

 

[prockish_90gsx]

Maybe balance shaft??? If you have them still...

 

[bsbllfit7]

haha to be perfectly honest im not sure if i still have the balance shafts or not, i think it is the lifters actually. Once i get the transistor and coil ill throw in some more oil (its a half court low) and see if that takes away the knock/tick. If so then ill be replacing all the lifters with some 3g revised lifters

 

[Ghost_92TSi]

! My 1g is doing the EXACT same thing. It does it around 2k rpms and it sounds like its on the driverside of the motor and like it is coming from the Valvetrain and not the bottom end. Mine does it everytime I hit the gas. I thought it was my cv shafts but when I replaced them and still had the sound I investigated further.

I don't have balance shafts.
I have low oil pressure all the time, how is the OP's oil pressure?