Burning Smell off and on sometimes bad. on 1998 Ford F-150

I got this car a few days ago from a used car lot. It has 182,000 miles on it and runs good. But when I first got it, there was a strong burning smell like rubber or something. It is usually like this after I start it and it warms up, or after driving it for a bit and then park it and turn it off. Lately I have also been having a problem with it sounding like there is a knocking noise when it is cold and then smooths out once it warms up. Thanks for the help James

by in Anchorage, AK on February 19, 2009
2 answers 1 comment
ANSWER by on February 19, 2009
I think you should get under the vehicle, at engine. Look for fluid leakage that may be dripping onto the exhaust/manifold. Could be an oil leakage, referring to bad gasket, etc.
ANSWER by on February 25, 2009
THIS HAPPEN TO ME, I FOUND OUT IF ITS A 4.6 ENGINE THE PROBLEM IS INTAKE MANIFOLD GASKET LEAKS OIL , IT WILL SOON START TO MISFIRE ON #3 OR #4 CYL AND CHECK ENGINE WILL COME ON, YOU WILL FIND YOUR LOOSING OIL BUT DONT KNOW WHERE ITS GOING, FORD USESD PLASTIC GASKETS AND THERE WAS A CLASS ACTION SUIT , YOU CAN TRY TURNING IN BILL FOR REPAI TO DEALERSHIP BUT DONT HOLD YOUR BREATH
COMMENT by on August 29, 2010
I have a 2005 Ford Explorer Sport Trac with a 4.0L SOHC engine. I was noticing a burnt antifreeze smell at times while driving. I didn't see any evidence of leakage on ground or from above and I also noticed my vehicle seemed to be using more gas. It would seem to lose power and act as if it didn't really want to "pull". I thought maybe I needed a tune-up. The check engine light wasn't coming on. I took it to a mechanic for a diagonosis. He performed a leak detector test on my truck and discovered it had a leak at the intake manifold gasket. Of course I'm very upset by this considering my truck is only five years old. I do have approx. 90,000 miles on the truck even so this problem should not be occuring this soon. I've owned Hondas and driven them over 200,000 miles without experiencing anything of this nature. I will be calling the Ford dealership Monday. I had another mechanic to diagnose the problem before going to the dealership because I realize they'll sometimes intentionally "misdiagnose" a problem to keep from admitting the company is producing poor quality vehicles. This is why so many recalls occur.