1994 Accord VTEC Engine/Trans Vibration
 

Hi All.

I have an odd thing happening to our 1994 Honda Accord VTEC with 191,000 miles. Between 2000 and 2500 RPMs on acceleration I get a pretty bad vibration. It mostly happens when it is in 4th gear but I have felt it at other speeds as well. I thought I remembered reading here someplace that it may be the torque converter starting to go out on the transmission. The other day I decided to check the spark plugs thinking it may be a missfire, but why would it just be at that RPM? I pulled all plugs, one had some oil on it from a leaking o-ring gasket but looked ok, but on the next 2 cylinders the spark plugs were all covered with a light powdery substance which I was told was a symptom of just running hot. I replaced the plugs and nothing changed. Before I take it in to the dealer and pay $120 just to have it looked at I wanted to ask the question here. Any ideas?

Thanks!!

RE: 1994 Accord VTEC Engine/Trans Vibration
 

How much oil on the one plug? Enough to short some of the spark to ground? Fuel mixture is more difficult to ignite at some loads & rpms, so a marginalweak spark can misfire under some conditions & fire OK otherwise.

Open the hood after dark, turn out all the lights, start the engine. Look for arcing around the cap & plug wires.

RE: 1994 Accord VTEC Engine/Trans Vibration
 

Hi.

I was thinking the same thing about the oil shorting the plug but I do not think it was enough to get up into the top of the plug. Wouldn't it affect the engine at all RPMs then if it was shorting? I did also try to look for arcing spark with the lights out, nothing.

Thanks.

RE: 1994 Accord VTEC Engine/Trans Vibration
 

If it was only shorting out a little bit(?), it could misfire in some conditions, but fire OK in conditions where the mixture was easy to ignite.

WhatI wanted was for you to check it, & it sounds like you did that & ruled it out.

RE: 1994 Accord VTEC Engine/Trans Vibration
 

Hi All.

Just an update. I did find out what the problem was, it was the exhaust gas recirculation system which is located under the fuel rail. 3 of the 5 ports were blocked solid. Cleaned those out and put it back together and the problem was gone.

RE: 1994 Accord VTEC Engine/Trans Vibration
 

Thanks for letting us know.