Broken Valve Spring? Or something else?
Left to go to a friends house, pulled into traffic, got in the gas a little bit, not to the floor, only got up to about 3300 rpm or so. When I got to the light to make my turn, car started shaking real bad. When I gave it gas to go, it puttered really bad, I didnt give it more gas, just held the pedal where it was, then it just revved like normal and went, but with a little jerk. Check Engine Light just comes on. I already know its a missfire code, dammut!
I get right around the corner from the light, shut it off for a minute, continued to my friends house just fine, which is only about 2 miles max. Got there and pulled the codes....300: Random/multiple cylinder missfire...152: o2 sensor circuit high volts.
Made one little run around the block, and it did it again once, then fine again. Car sat for the nxt 2 hours.
Started the car up to leave, after about 10 seconds, it idles down to about ~500 or so and holds it, but the whole car is shaking, not vibrating, shaking. So I unhooked the batt for about 10 minutes, left to go home, car starts it again a block away.
1st light car starts actin bad again, so I shut it off, turn it back on, no help. Pulls a 302 code now too, start to accelerate, it putters, I hold the gas steady, not giving it more, it bogs, then goes, bogs, then goes. At this point I was mad and ready for it to blow. Next light, it idles about 550-600, but no shaking, and continues on home for the next mile or so no problems.
The engine isnt making any noises, no ticks or clicks. One buddy is suggesting a broken valve spring. He's broken them before and had them not make any noise, his opinion is valued, so Im planning on pulling a valve cover tomorrow too. I still havent pulled the plugs in this car since Ive owned it, for about 4 months now. Car is stock with mods listed, and 191k miles. Any other ideas?
Your my hero, lol (I have almost 140K-makes me feel better about my car)
Give it a full tune up first, meaning change the plugs and wires. For plugs, I'd reccommend AC Delco Platinums or Iridiums, or NKG Iridiums. For wires, I'd go with either the stock AC Delco ones, or Granatelli wires. I have the AC Delco Iridiums and Granatellis, and I've been happy with them.
I seriously doubt its a broken valve spring, the car shouldn't run that bad unless the spring was completely destroyed, and you'll almost always hear the tick tick tick from the broken spring.
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Oh and be careful when taking high mileage rocker arms off mine didnt comply with me...so i killed it..

Now the only wire I didnt pull yesterday, was #8. The wire contact broke off on that spark plug (3rd in the pic) and prevented me from getting the socket on it, I dont know if I broke it off trying to get the wire off, or maybe that was the problem. It was me that broke the plug itself though.
I did pull the valve cover since I was there, everything is good on that side too. Starting to get a little worried as to my problem.
This is the best pic I could get with my crappy little camera, but you get the idea, they look fine. They are NGK's incidentally.
Last edited by WS6NIGHTMARE; Jan 23, 2007 at 06:03 PM.


how about your coil packs? i bet they're original. no one ever thinks to change their coil packs, so i bet they have 191k miles on them
perhaps you need new coils.
perhaps you need new coils.
I guess I could do that while I wait for dinner....search better be working....
I guess I could do that while I wait for dinner....search better be working....
my advice to you is to go to napa, autozone or advance and buy one coil. it'll run you $50-$60. what you do is, you take off cylinder 1 coil and replace it. see if the problem's still there. if it is, take off the cylinder 2 coil and see if the problem's still there. keep trying until you find the bad coil. of course, it's possible that more than one has gone bad, but make no mistake, all 8 haven't gone bad at the same time
IMO, you should replace all your coils anyway. i mean they have nearly 200k on them. it can't hurt.
my advice to you is to go to napa, autozone or advance and buy one coil. it'll run you $50-$60. what you do is, you take off cylinder 1 coil and replace it. see if the problem's still there. if it is, take off the cylinder 2 coil and see if the problem's still there. keep trying until you find the bad coil. of course, it's possible that more than one has gone bad, but make no mistake, all 8 haven't gone bad at the same time
IMO, you should replace all your coils anyway. i mean they have nearly 200k on them. it can't hurt.

hope you get it working 