camaroeater

Once i give it about 3/4 to full throttle, i can feel a vibration from under the hood that shakes the dash. Its not cutting out or studdering at all and I don't feel any loss of power.

It kinda reminds me when my balancer went out, but that sent vibrations around the shifter. I also thought maybe the driveshaft, but the vibration is not velt on the floor. I pulled codes and got a code 31(egr voltage low). I tred bypassing the egr valve by unpluging it and capping off the ends, but that didn't help.

Any ideas what it could be or what I could check? Oh yea, I changed the spark plugs, and inspected the cap, rotor and it looked fine.

daredevil95

Check the tranny and engine mounts!

camaroeater

I checked the tranny mount recently, but I will take a look at the engine mounts. I don't understand, it idles perfect, but vibrates from the front when I get on it. As far as a code 31(egr voltate low) could this cause these symptoms?

daredevil95

Low voltage could give a stalling effect.......starving for gas like feeling. What is your volt gauge reading? Rev it up and watch if it's dropping.....if it's not dropping the charge system is good. Could also be the distributor having issues with volts.....what's the condition of the cap/rotor/wires & plugs? This could all appear good but, the distributor could be out of wack. You would have to bring the distributor to a garage and have them test it....at that point....price wise you could buy a new distributor. Good luck

P.S. start off with the mounts....they tend to brake.

camaroeater

I cleaned the egr position sensor and the connectors, then applied some dielectric grease to the pins in the connector. I took it for a ride and it doesn't vibrate when i go WOT. It seems that instead of the egr going into the closed position at WOT, like is supposed to. It was staying open or somehthing.

I cleared code 31, ran KOEO and code 31 is gone now.

daredevil95

Easy fix....awesome!

whiteNblack95

have you replaced your harmonic balancer?

camaroeater

The vibration is still happening. My car idles perfect with no vibration. The vibration seems to happen above 2k rpms and increases when i go WOT. I can really feel it on the freeway going 55mph+. If i let off the gas, it goes away.

What go you guys think? It not pulling any codes and seem that something is barely off.

lxman1

Pull the plugs and see how they look. Seems to be misfiring under heavy load, so it could be a weak plug or a plug wire arcing somewhere. Could even be a weak coil, partially clogged fuel filter or injector.

camaroeater

I replaced the coil a little over a year ago and just did the spark plugs and the fuel filter. I thought maybe it could be an injector too, but wouldn't it hesitate real bad? It seems to be shaking around the dash and the floor, but it stops once i let off the gas.