Az_NavajoRob
Active Member
- Joined
- September 15, 2004
- Messages
- 50
- Reaction score
- 0
- City, State
- Tucson, Az
- Year, Model & Trim Level
- '91 Navajo
Okay guys, here's the deal. I rescently bought a '91 Navajo that needed cyl heads (and radiator, heater core, starter, battery, altinator, etc.). After doing all this work, it generally runs great. I say generally because sometimes it feels like it's down on power, like it's dragging an anchor. Other times it feels fine and has plenty of power. Also, I get pretty crappy mileage (12-13 mpg). It passed emissions fine and there is no fuel leak so my thought is that the computer is retarding the ignition, like in response to poor fuel or engine knocking and that's what is causeing the loss in power. I run 87 octane (the cheap stuff) and have never had a hint of pinging.
My question is this-is there a knock sensor that could be bad telling the computer to retard the ignition timing? Would this show up if I pull codes? If there is no knock sensor then how does the computer know how to alter the timing? Does it use the air intake temp sensor for this purpose? If so, would one of those $10.00 "chips" (you know, the little resistor that plugs into the harness instead of the temp sensor to fool the comp into thinking the air being drawn into the engine is at 0 degrees) keep the computer from retarding the ignition?
Any advice or thoughts on this subject would be appreciated, including any experience with those "cheater chips" that fool the computer as described above.
My question is this-is there a knock sensor that could be bad telling the computer to retard the ignition timing? Would this show up if I pull codes? If there is no knock sensor then how does the computer know how to alter the timing? Does it use the air intake temp sensor for this purpose? If so, would one of those $10.00 "chips" (you know, the little resistor that plugs into the harness instead of the temp sensor to fool the comp into thinking the air being drawn into the engine is at 0 degrees) keep the computer from retarding the ignition?
Any advice or thoughts on this subject would be appreciated, including any experience with those "cheater chips" that fool the computer as described above.