OK, '92 cherokee. New o2 sensor, rugged ridge air intake, E3 spark plugs, Magna flow muffler, ect... But, the milage has gone down. Do I need to "reset" the ECU? and if so, anybody out there able to tell a shade tree how?

 

There was a thread here a little while back saying that the I6 doesn't like the E3 plugs too much and it was recommended they be changed. Sorry I can't remember the suggested brand to switch to.

 

Resetting the ecu on a 92 is as simple as disconnecting the battery.

 

Well that's easy enough to do. Thanks guys, I'll have to do some searching on the E3 plug thing. So far it doesnt seem to mind them much at all.

 

ok. air-fuel-spark.
all 3 need to be equal and relative to each other. if you increase the amount of air, or get colder air to the engine, it needs more gas to match the added air mass and more spark to burn it more effectively. the "air" part is controlled by both the intake and exhaust pressure. you know when you see that ricer sitting there with an exhaust big enough to fit an elephants dick? well, unless that engine is sucking in a ton of air, buring it hot and with GOOD compression, then hes probably gotta keep his rpm's up or it will stall... see where im going? so the principal of "more" doesnt always play out as expected. if you want better gas milage, one) get a prius... hahaha.

no, seriously:
-dont go to jcwhitney and order the ricer special: a short ram intake, TB spacer, and cat-back wont do **** for gas mileage. it will, however, make your friends hate you, give you like 5, maybe 10 more ponies and all at the sacrifice of gas mileage.
-smaller, highway radials for tires are good
-new cap/rotor, plugs/wires
-run sea foam thru your gas and in your intake (get a buddy to keep the rpms up from the drivers seat, or it will stall)
-get a good tune up done: compression test, ALL FLUIDS changed, seriously, this makes a big difference.
-check for vac line leaks.
-check tire pressure.
-i wouldnt recommend this anyways, but with gas prices the way they are, dont bother running a higher test gas...
-before using sea foam, pull your TB off, take off the IAC and TPS, and clean the hell out of it with TB cleaner NOT carb cleaner. carb cleaner will aparently take the finish off the TB and leave it sticky... idk, untill just recently, carb cleaner was what you used on a TB... but not anymore...? ok, good luck!

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