93 SE vibration 2-2.5K RPMs

So I posted a while ago about a problem I was having with my 93 SE, it was Vibrating, "missing" and shuddering at just about any speed, and was worst at 2-3K RPM's under load. It turns out my EGR valve was clogged up, after a nice cleaning my problems just about all went away and I had a way better driving experiance. however I still have slight power loss and vibration at 2-2.5K RPMs under load, in very little 3rd, slightly 4th and very noticeable in 5th, I figured it was still my EGR valve and something was wrong with it all together. about a week ago I seafoamed my car in hopes that it would help clear up the EGR, althought it helped clean everything out, it did not help my vibration. I got a donor EGR valve from my friends 93 V6 LE that he rolled, everything worked great on it to date. I installed this egr valve and my problems are still there, they were decreased though, my 3rd gear has extremely little to no vibration, 4th is insignificant and 5th is a little less harsh, but still jaring. Checked ignition, vacuum lines, CV's, got new tires(i needed new tires anyways, and some of my highspeed vibration that I had from the old tires is gone) and I have no CEL. and I am getting pretty terrible fuel economy, Ill admit I drive a little hard sometimes, but even when I keep it down I still only get about 250-300 miles on a tank. so heres my questions.



1. is it possible that the "new" egr valve is bad as well?

2. is there a difference in an Auto tranny EGR and Manual?(they look identical but have 1 number difference)

3. What can cause a Vibration at these RPM's under load?

4. is it just the design of the tranny that makes it not operate at the low rpms/high gears?

Reply 1 : 93 SE vibration 2-2.5K RPMs

anyone?

Reply 2 : 93 SE vibration 2-2.5K RPMs

I have a slight vibration at anything under 3000 rpms or so. Mine does not feel motor related, it feels suspension or axle related. I have new pass axle. So not that. It feels like I am running over mini turtles in the roads. Not harsh ones just small vibrations. 93 se also

Reply 3 : 93 SE vibration 2-2.5K RPMs

hmm... how man miles on it? did you check the plugs? sounds similar to my problem when i first put my S/C on. one plug was cracked and under load at lower rpms it would miss-fire a little. the more load, the worse it was. also, how old is the cat? it may not be the source of the vibration (though a blocked cat can screw with the exhaust flow in a way that could cause it) a blocked EGR is a sign of extra deposits that may be clogging your cat and causing the power loss and bad mileage.

Reply 4 : 93 SE vibration 2-2.5K RPMs

Quote:

Originally Posted by bigbird hmm... how man miles on it? did you check the plugs? sounds similar to my problem when i first put my S/C on. one plug was cracked and under load at lower rpms it would miss-fire a little. the more load, the worse it was. also, how old is the cat? it may not be the source of the vibration (though a blocked cat can screw with the exhaust flow in a way that could cause it) a blocked EGR is a sign of extra deposits that may be clogging your cat and causing the power loss and bad mileage.

180k miles, on the sparkplug, I checked the front three and the back passenger side bank thats easy to get to, they all look fine, probably really did get a tune up when the guy said it was. plus its not a miss, its a true physical vibration. as far as the cat, im getting a custom Y pipe and highflow cat soon, but the cat isnt purple so I dont think its clogged, could be a little stuffy though. I have a feeling its a multi system problem, and I do think the cat is on its way out, because there is a bit of a bad cat smell from the exhaust.

Reply 5 : 93 SE vibration 2-2.5K RPMs

Quote:

Originally Posted by 1BADBAJA I have a slight vibration at anything under 3000 rpms or so. Mine does not feel motor related, it feels suspension or axle related. I have new pass axle. So not that. It feels like I am running over mini turtles in the roads. Not harsh ones just small vibrations. 93 se also

yeah same here, but mine only really occurs at 4th and harshly at 5th gear, it shakes the whole steering wheel assy and you can feel it a bit in the seat. 3rd gear gets it a little at 2.2k rpms and then its gone less than .2k rpms later. nothing in 1st and 2nd. didnt think about axles.