Questions and Answers
Oil Burning Neon
Q. Hi Vincent, I recently purchased a 1997 Dodge Neon (SOHC, 2.0, 4cyl, manual 5-speed) from my neighbor and it wasn't kept up very well mechanically, but is in surprisingly good shape. It currently has 82,000 miles on it and at about 79,500, I changed the spark plugs and wires,(for the first time!),and the gaps were huge and the plugs were covered in oil and 2 were covered in carbon.
My MPG went way up and I was happy with that. I just pulled them the other day to check up on the gaps and noticed that the plugs on the #2 and #3 cylinders were covered in oil. I was wondering what could be causing this? Rings on the pistons or is there a seal somewhere that could be leaking. I am still getting about 40 MPG highway and 25 MPG city, is this still something I should worry about? I am hoping it is an easy fix like when I fixed my big oil leak that I thought was the head gasket with a $5.00 O-ring on the cam sensor, but I am doubting it now.
Thanks for your time, looking forward to your expert input.
TomA. Oil on the plugs is never good. What you need to do is a wet/dry compression test to determine where the oil is coming from. First a dry test is done and the compression is noted. The compression should be about 160 to 180 pounds. More important than the actual reading is that they are fairly equal between all the cylinders.
One the dry readings are noted, then a couple of squirts of oil are shot into the cylinder. This has the effect of improving the ring seal. If the readings go up significantly, then you have worn rings and the engine needs an overhaul. If the readings only increase by a small amount, then it indicates the problem is with the valves, most likely the valve seals. If this is the case, replacing the seals is relatively easy and inexpensive.
FYI: There was an informational TSB on that seal you replaced. I quote from the bulletin: Whenever performing oil leak diagnosis on one of these models carefully inspect the cam sensor area to determine if the leak originates from the seal or from other sources. A leak in this area can be mis-interpreted as a leaking head gasket. Additionally, whenever a head gasket is replaced, the cam seal should always be replaced to prevent the possibility of the vehicle returning with oil seepage.
Additional Information provided courtesy of ALLDATA
