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.

 

[TALONTRAX]

When was the last time you replaced the plugs & wires ? Sounds like an ignition misfire - check your plugs & wires

 

[bsbllfit7]

I got new plugs and wires maybe 5-6k miles ago. I have not however gotten new cool packs. Why would somethin be ratteling if it was ignition related though?

 

[esoteric]

Did you check your timing, if you skipped a tooth and dinged up some valves it would still run and be doing what you are describing

 

[bsbllfit7]

I took a brief look at the timing and made it so the marks on the ams ligned up so I don't believe that is the issue. It definitely feels ignition related but the thing that got me was why it would idle just fine and start right up. But then when you rev it it rattles and also misses when driven in gear

 

[TALONTRAX]

Can`t explain the noise . . . But the jumping tach is an indication of an ignition breakdown. Could be the coil pack, or also the transistor. Look closely at the coil pack, maybe when its idling, look for any arcing near the plug wire boots. I used to spray a fine mist of water from a windex bottle at the wires & coils to help find an arcing wire or coil . . .

 

[bsbllfit7]

ok I'll do that and possibly start at the coils. Where is the transistor located. I'm not extremely familiar with ignition systems.

 

[XiKeiyaZI]

Just because your cams line up, doesn't mean that it didn't skip a tooth at your crank.

Pull of your crank pulley and line it up at the crank and THEN check the cams.

It sounds like a tooth skipped. Check that first and then move on to ignition. I normally say start small and work up... but when it comes to timing, don't ever take a chance of just "thinking" it's okay.

 

[vzeoh6om]

check the terminals at your battery......i had a similar problem a while back and thats what it was....your problem definently sounds ignition related tho

 

[bsbllfit7]

if the timing was off though wouldn't the idle characteristics such as vacuum and rpms be off?

im about to go back to the car on the highway right now and have it towed back home. Anything i should look for while im out on the road? Ill rotate the timing too make sure. Also i will check for arcing at the coil packs.

 

[Thor25X]

Check the black plug above the spark plugs. It controls firing of the spark plugs... I had the EXACT problem. I pushed it back in and it worked fine. So i'd check that.

 

[bsbllfit7]

my problem is not that plug it was seated all the way down, i think my next thing is to go to the junk yard and get two new coils. If it is the coils then ill fork out some money for some good msd ones or something but want to make sure of the problem. The misfire doesnt always happen just during revs and when driving ###### once very 4-5 seconds or a little more

 

[XiKeiyaZI]

Did you verify timing via the crank Vs the CAMS? Just want to be clear that the crank can skip a tooth and the CAMs can be in perfect time. It may run fine at idle and low RPM. At higher RPMs the car would run funky. Vacuum wouldn't change noticeably unless it was 2+ more teeth. I think at 3 teeth is where you start slapping valves.

^^ Just verify it's been checked properly before you go tossing money left and right.

 

[bsbllfit7]

alright im going out right now to rotate the cams/crank by hand to tdc to verify timing. I will also test the timing with a timing light. I have done the 1g cas swap. These wouldnt be symtoms of a bad CAS would it?

 

[XiKeiyaZI]

alright im going out right now to rotate the cams/crank by hand to tdc to verify timing. I will also test the timing with a timing light. I have done the 1g cas swap. These wouldnt be symtoms of a bad CAS would it?

Uhm... I can't say yes or no. It sounds like it SHOULD be related to the CAS...as that deals with ignition. I haven't done the CAS swap onto my own engine yet so I have no knowledge on the effects of it if it starts to go out.

Start with mechanical timing. Verify that it's correct. Mechanical timing be off is a very potential danger for your engine. Should be priority #1.

 

[bsbllfit7]

whats the timing mark on the crank look like again. Lol its been awhile

 

[XiKeiyaZI]

whats the timing mark on the crank look like again. Lol its been awhile

Haha.

For ignition timing, it's a notch in the middle lip of the Harmonic Pulley.

For MECHANICAL timing. You need to take off the 4 bolts that hold that pulley on (requires removing your belts) and remove the pulley. On the actual crank plate behind the Timing Belt, there is a 'V' shaped notch taken out of the plate. There should also be an arrow-like shape cast on the block. The Arrow should point to the Notch in the Crank plate.

When it is lined up perfect, the notches on the CAM gears should also be lined up, even with the seam where the Valve Cover and Head meet.

 

[bsbllfit7]

so timing is perfectly set both ignition and mechanical. When i started the car up cold it still rattled a bit but drove fine. As the car heated up i ran into problems and started having misfires. Im posting a video now of some revs with it good than suddenly going bad. Idk if it is the cas or the coils but im guessing one of those too. Also still no clue what the rattle is as it isnt a rod knock or anything like that and isnt present at all times!

<object width="480" height="385"><param name="movie" value="http://www.youtube.com/v/cRWaAxnkeok?fs=1&amp;hl=en_US"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/cRWaAxnkeok?fs=1&amp;hl=en_US" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="480" height="385"></embed></object>

here it is, the rattles when in the front shots are at about 2k rpms but after that it goes away!

 

[GsXdSmKingGsX]

I took a brief look at the timing and made it so the marks on the ams ligned up so I don't believe that is the issue. It definitely feels ignition related but the thing that got me was why it would idle just fine and start right up. But then when you rev it it rattles and also misses when driven in gear

Thats what I was gunna say.. And thats the freakin wierdest noise Ive ever heard in your video.

 

[bsbllfit7]

could this be symtoms of a bad 1g cas too or is this almost certain to be coils/

 

[talon187]

it sounds like somthings knocking or hiting? do a compression test? could timing belt tenisor but ive never heard it knock like that its always ben a loud tick

 

[bsbllfit7]

ok im heading out for the night but tomorrow i will do a compression test first thing when i come back! Post up any other ideas! Its weird cause its not at all times like rod knock or something like that, could it be somethign broken in the transmission or something broken in the valvetrain?

alright so got back and did a compression test. I had 170 in cylinders 123 and 160 in cylinder 4. That should not be a cause for concern with a higher mileage motor correct?

 

[bsbllfit7]

Alright so I forgot to let the engine warm up before I did the compression test. Went back and did it today came up as 170 on all four cylinders. What to test for now?

tried switching out the plug wires today and same thing happens. The car runs magnificently until the engine gets warm and reaches normal operating temperature. Anyone with any information that could help me out?

alright would it be better to go coil on plug setup or go and get new coils. I mean it is 180 for the two coils and idk how much cop's go for but it seems easier!

 

[vzeoh6om]

alright would it be better to go coil on plug setup or go and get new coils. I mean it is 180 for the two coils and idk how much cop's go for but it seems easier!

i think it would be best to try and find the problem then fix it instead of throwing parts at it to try and mask it....from the video i dont know if its my speakers or the quality bout ive never heard a knocking sound like that...it kinda sounds like a knocking from fuel detenation over here....

 

[bsbllfit7]

ya im getting new coils tomorrow or the next day, the knock is there as i start the car then goes away at idle. Then only knocks in like first gear and thats it! Could it be transmission related? Idk what the hell would be knocking in the transmission but its my only guess.