Join Date: Apr 2010
Location: Lawrenceville, GA
Fuel Mileage / Vacuum / Timing Issues Jeep 1993 YJ
I have been fiddling with my first jeep that i just bought a few weeks ago for a while now and have not had much luck. Here is a detailed explanation of what i have been through so far with my current issues at the very bottom next to the *.
1993 Jeep Wrangler YJ 6 cyl. 4.0
Bought a 1993 Jeep Wrangler at a great deal that had new wires, plugs, cap, rotor. Pretty much a complete tune up. My drive from the seller to my house was approx 44 miles so i filled up the Jeep and by the time i got home i was on 1/8 of a tank so almost a full tank. I noticed Carbon coming out of tailpipe heavy like powder.
I then pulled the plugs and started to try to diagnose the problem which i first thought it could be catalytic converter but temperature came out good on that, and also had it checked through emissions and it was good. So i proceeded to the Fuel Pressure Regulator and changed it out and noticed a vacuum line that goes to it had dry rotted rubber boots so changed them out too. This did not fix my problem So i proceeded to the next avenue and cleaned up the Air Intake Control Valve and it was caked up with carbon also and since the idle control valve is right next to it i went ahead and changed it out just for kicks since it was only 12 bucks.
Now i thought this would help it at the least but instead my idle went from running around 1100 rpms up to about 800 rpms with surges up to 1500 rpms.
This obviously didnt do any help. So i went ahead and drove it to hope to clean it up and nothing helped so started to go over with a fine tooth comb.
"Remember this is my first 4 wheel drive and first Jeep" so i get underneath it and notice i have 4 vacuum lines that run off the back of the transmission up to my firewall area that have come in contact with my exhaust and have all melted together (Thank god in a way i could tell which one went to which after i cut and spliced them all together.) So now i crank it up and im running at a smooth idle about 850 rpms and when i drive i feel like i have more torque and the engine is no longer skipping any. So i am assuming these vacuum lines are all intertwined from the transmission up to my fuel line areas and etc. Have not had a chance to drive it on a long distance drive yet.
**Here is my current issue now... When i drove it home from fixing those lines about 5 miles away i can still smell the unburnt gas faintly (not as bad as before) while driving. And when i accelerate going through my gears the check engine light will come on only when my foot is on the pedal. once i release the fuel pedal the light goes out or once i get into 4th to 5th gear the light goes out also. So since that has been going on since the beginning i am assuming i have yet to track down my problem**
CAN ANYONE HELP?