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Topic Review (Newest First)
08-24-2013 05:26 PM
banks316
Quote:
Originally Posted by Matches View Post
Backwards.
My bad... Thanks
08-24-2013 04:47 PM
Matches
Quote:
Originally Posted by banks316 View Post
Another thing that gets over looked...Engine temp... must be over 195 degree or the ECU stays in a closed loop mode. So heres deal on that. Your ECU has two modes close loop and open loop. Close loop mode is used for start up, it helps get the engine to operating temp buy burning more fuel and pretty much ignoring the O2 sensor. Open loop triggers when the engine is at operating temp. It then adjust fuel air mixture based on what the O2 sensor is telling it. There is a coolent sensor on the tstat housing that wouldnt hurt to replace. This sensor is for the ECU not the guage.
Backwards.
08-24-2013 12:22 PM
ddtt225
Quote:
Originally Posted by deepak View Post
so i opened up the oil pan to replace main seal.. it seems like it's losing comresssiong
referring to his post guys. I know you cant tell compression by dropping the oil pan and that you need a compression tester. I was just trying to figure out how he knows he has low compression by just dropping the oil pan.
08-24-2013 12:10 PM
banks316
Quote:
Originally Posted by ddtt225 View Post
how can you tell by dropping the oil pan that your losing compression?
You cant, you need a screw on compression test guage. It goes in the spark plug holes.
08-24-2013 12:09 PM
ddtt225 how can you tell by dropping the oil pan that your losing compression?
08-23-2013 04:43 PM
banks316 Another thing that gets over looked...Engine temp... must be over 195 degree or the ECU stays in a closed loop mode. So heres deal on that. Your ECU has two modes close loop and open loop. Close loop mode is used for start up, it helps get the engine to operating temp buy burning more fuel and pretty much ignoring the O2 sensor. Open loop triggers when the engine is at operating temp. It then adjust fuel air mixture based on what the O2 sensor is telling it. There is a coolent sensor on the tstat housing that wouldnt hurt to replace. This sensor is for the ECU not the guage.
08-23-2013 03:58 PM
miked196 x2 on the o2 sensor
03-13-2012 02:04 AM
deepak yes the speedometer is correct.. i checked it with my gps...time to rebuild the engine.. gonna do the comression test then ill ask you guys if i have any questions..
03-12-2012 12:01 AM
Z-TJ Did you change your speedo gear?
03-11-2012 11:55 PM
Xpress
Quote:
Originally Posted by deepak View Post
yes the speedometer is correct.. thank you for your guys's advise
Are you sure? Did you re-gear the speedometer?
03-11-2012 10:42 PM
deepak so i opened up the oil pan to replace main seal.. it seems like it's losing comresssiong
03-07-2012 10:19 AM
deepak yes the speedometer is correct.. thank you for your guys's advise
03-06-2012 09:15 PM
jdeere_man This may seem to be a stupid point, but is your speedometer correct? If not (incorrect Speedo gear) your odometer is not adding miles correct. If you are figuring your gas mileage of an incorrect odometer that doesn't help.
03-06-2012 07:52 PM
Xpress Disconnect the positive and ground it out on the negative. It shouldn't spark or do anything, just drain the caps in the ECM, which is what resets it.
03-06-2012 03:48 PM
Garyk x-2 good advice.....to reset your ecm, disconnect the battery for a few minutes..
03-06-2012 12:27 PM
Xpress You have a 4.0 I6, not a V6. A V6 engine indicates that you have 6 pistons in a V shape, 3 pistons on one side, 3 pistons on the other. An I6 engine has all 6 pistons in a straight line. Basically I6 stands for Inline 6. Jeep never included a V6 engine in the Wrangler until the newer 2007+ JK models.

You need to do a FULL tuneup. That includes replacing EVERYTHING that is replaceable as a part of maintenance. I'm not entirely familiar with the 4.0, but here is a basic list of parts for you to go through and replace:

-Air filter (stock ones work just fine)
-Fuel filter (people always skip this one)
-Distributor cap
-Distributor rotor
-Plus
-Plug wires (all 7 of them, even the one coming from the coil to the dizzy)
-Remove the throttle body and scrub it out by hand with cleaners and a toothbrush
-Oil change (don't forget the filter)
-Replace PCV valves (if it has one, not entirely sure)
-Replace ALL vacuum tubing- it seems like a PIA but even a small leak can cause your engine to run odd
-Replace O2 sensor (get an OEM, Bosch O2's often fail prematurely)
-Replace MAF
-Flush out old coolant, replace with new GREEN coolant

And once all of the above has been done, run a good quality fuel injector cleaner inside of your gas tank- you need to have a full tank for the full bottle otherwise it won't work as intended.

Double check for exhaust leaks as well, between the exhaust manifold and the O2 sensor. All it takes is for that O2 sensor to see a little bit of fresh air and it tells your ECM to dump more gas in.

If your engine doesn't run like new after that then you have something else amiss, such as a faulty ECM, or a bad injector not working properly, or something else. Remember to re-set your ECM after installing the new MAF and O2.
03-06-2012 05:35 AM
DirtyRob Another option is take it to a mechanic that you trust, and let them look at it. You can throw parts at it and spend more money than repairing what it actually wrong with it, unless you just feel it needs a lot of stuff anyway. Good luck
03-06-2012 02:30 AM
banks316
Quote:
Originally Posted by deepak View Post
its's a 4.0l v6 with like 2 inch lift kit only...so i was thinking about going with k and n intake (the roundy roundy filter) but im not anymore. so how about fujita and any other brand recommendation.. it just passed smog like 2 monts ago so im assuming that it's not catylic converter.. i'll replace the oxygen sensor.. and should i get the valve tuneup done? and any other recommendations
There's your problem you don't know what you. 4.0l are online 6 not a V
03-05-2012 10:36 PM
Frenz Hellz yeah reset the ecu.
03-05-2012 10:36 PM
GrayYJ If you change your converter, you are also going to want to change plugs.
03-05-2012 10:16 PM
deepak so what is should do at this point is leave the bosch plugs, get new oxygen sensor, and new catytic converter... any air intake suggestions and how to fix the enrich fuel mixtured.. should i reset the computer to see what happens..
03-05-2012 08:12 PM
DirtyRob
Quote:
Originally Posted by dmcg View Post
Does it have a lift? Is it a 2.5 or 4.0? What year is it? You need to include these things. 2.5s with a lift get worse gas mileage then the 4.0s. Also, Jeeps like champion plugs the best. Replace your air filter with an AC delco. Don't use K&N. A failing catalytic converter will also give you crappy gas mileage and loss of power.
Jeeps get crappy gas mileage regardless. I'm lucky to get 15mpg in the city
You took the words out of my mouth. I don't know why but it is true about Champion plugs. The other suggestions are very good too.
Does your exhaust smell like fuel? If so you are runnig way rich
Does your floor get real hot behind the passenger seat? If so your cat converter is going bad. Just two things that come to mind to narrow it down.
03-05-2012 03:13 PM
deepak and the year is 1992
03-05-2012 03:13 PM
deepak its's a 4.0l v6 with like 2 inch lift kit only...so i was thinking about going with k and n intake (the roundy roundy filter) but im not anymore. so how about fujita and any other brand recommendation.. it just passed smog like 2 monts ago so im assuming that it's not catylic converter.. i'll replace the oxygen sensor.. and should i get the valve tuneup done? and any other recommendations
03-05-2012 02:42 PM
banks316 O2 sensor
03-05-2012 02:34 PM
dmcg Does it have a lift? Is it a 2.5 or 4.0? What year is it? You need to include these things. 2.5s with a lift get worse gas mileage then the 4.0s. Also, Jeeps like champion plugs the best. Replace your air filter with an AC delco. Don't use K&N. A failing catalytic converter will also give you crappy gas mileage and loss of power.
Jeeps get crappy gas mileage regardless. I'm lucky to get 15mpg in the city
03-05-2012 01:47 PM
deepak
Really really low gas mileage

So i originally had 35 inch tires and my jeep gave 8 mpg. So then i decided to put stock wheels and tires. The jeep didn't do any better. It just improved by 2mpg. After that i put in new bosch platinum 2 spark plugs, new wires, new rotor and rotor cap.. The mileage is still around 10mpg with everything stock.. Any suggestion on what should i do next to improve it little bit.. I suspected it's fuel injectors so i put lucas fuel injector cleaner and still no luck.. Any other suggestion/ideas on what i should do to imporove it.

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