1992 honda civic lx, 5sp 200K. Blown head, tried Blue Devil, didn't work had the gaskett replaced, head was pressure tested and all that, timing belt replaced, oil changed as well. It runs good, but whenever it gets to normal temp after 10-12 miles...when I come to a stop and it idles down, the oil light comes on, if I give it some gas it goes out. I took it back to the mechniac and he adjusted the idle on it and turned it up and said that was all he could do, he said that the car is just old and worn and its going to happen, he says it won't hurt anything that the oil is just thinning out when its hot and tripping the sensor(it does it quicker if I run the AC too since it idles it down further) the oil light never came on before this and I have had it for 3 years. He also said it COULD be due to the fact some of the blue devil gasket stuff was inside the engine block, he said he got all he could off, but there was still a little hardened in there. it never does it cold, just once its warmed up and when it idles down as low as it will go. Has he messed something up? WILL it indeed hurt something doing this? I get 38mpg and want to keep it unless its hosed at this point. The car is almost perfect inside and out and everything works on it, thats the reason I got it fixed to begin with. I dont mind the light IF IT won't really hurt the engine. Now I thought about draining the oil and trying a thicker oil, but not sure that would matter a lot. The mechniac said it might help, but he doubts it....Please help me out guru's! Thanks!

 

IMO it sounds like you need to find a different mechanic..

When you did the oil change, what type of oil did you put in?
Is the oil at the correct level...?

 

Try just doing and oil change, drain your oil and replace the filter with some new oil. My oil pressure light will come on when im getting low on oil during start up, once i top it off the light no longer comes on. If there is in fact stuff in your oil just change it and get it out of there before/IF it will infact mess anything up.

 

I asked about the oil they used and he first said 10/30, I said well it calls for 5/30 and he said...oh yea we used 5/30...so not 100% sure...I did check the level and it was full, now I did add a little extra hoping it would help...I bought a quart of 5/30 high mileage because it says its a thicker oil(not sure if it is or not) I am not a mechanic by any means, I can do simple things, but over my head here....I thought about just selling the car, but hate to let it go if nothing is REALLY wrong.

 

Well first ya get rid of your mechanic, 2nd that probably your problems, if 5/30 is thicker than 10/30 and "thin" oil is tripping a sensor then change your oil with 5/30. Dont mix them.