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I just joined the forum. I have an '89 4.9L inline six F-150 which suddenly began loping and blowing black smoke out the exhaust. I've been checking for vacuum leaks and I intend to check my PCV, EGR, IAC, etc. Considering the difficulty I'm having finding the PCV, I thought I'd ask for a little guidance from other members as to the location of these items. I'm sure that in time I'll find these components, but what the heck! Why not make it easy on myself and tap into the tons of experience in this forum?! Thanx.
I checked the MAP, lines and connections. I subsequently purchased a Fault Code Scanner and ran a KOEO (w/Continuous) Self-Test. The codes were as follows: KOEO - 67 (Neutral Pressure Switch Circuit Open and C - 32 (EGR Pressure Feedback Fault). First of all, my manual (Haynes) doesn't even mention a Neutral Pressure Switch. The only switch I can think of that might apply is the switch that is on the clutch assy. which doesn't allow you to start the engine unless the clutch is engaged (which doesn't seem related). I've located the EGR and EVR; but, my Code Scanner Book advises that the KOEO problems be corrected before you proceed to the C problems and beyond.
As I said earlier, my truck is a 1989 4.9L, inline six with 5-speed manual transmission and fuel injection.
67 means you did not have the clutch pedal down during the test.
Service Code 32 in Key On Engine Off and Key On Engine Running indicates that the EGR valve and/or EVP sensor voltage is lower than normal in the closed position. The EVP voltage is less than the closed limit voltage of 0.24 volts. Because of the preload of the EVP sensor it is very difficult to determine whether the EGR valve has malfunctioned or the EVP sensor has an abnormally high resistance.
I felt a bit sheepish when I read your comment about the "67" code (smile), especially after discussing it with my spouse (she was helping me by holding the clutch down during the test). After careful consideration, she admitted that she MIGHT have been depressing the brake. We ran the test again, and it came up "11" KOEO (good) and, again "32" (C).
I checked the input voltage to the EVP and it was within tolerances. The manual mentioned a resistance check using a vacuum pump. I have a pump but no gauge; however, I'll try to run the check tomorrow the best I can without a vacuum gauge. I'll let you know how it comes out...and BTW... Thanks a heap for your assistance.
Semperfi just bought an 89 with the 4.9 also and the pcv valve is located behind the intake on the valve cover there is only one hose going to it and it is not easy to find, I had to get up on the radiator support to find it after searching inside the engine bay forever good luck with your truck