Okay. I'm gonna try looking for answers here one last time before I head to a shop.
Newbie
Joined: May 2016
Posts: 1
Likes: 0
Model: Cherokee
Plugged 🐈.
That's what I've been wanting to do but everyone says "converter glowing red just means it's running very rich and the converter is burning a bunch of extra fuel but the converter itself is fine."
Also, I unbolted the entire exhaust from the exhaust manifold and ran it open header with the o2 sensor plugged in and it ran just the same.
Also, I unbolted the entire exhaust from the exhaust manifold and ran it open header with the o2 sensor plugged in and it ran just the same.
Best of luck bro
CF Veteran
Joined: Nov 2017
Posts: 3,700
Likes: 238
From: Groton, MA
Year: 1995
Model: Cherokee(XJ)
Engine: I6 4.0L
LS coils? What is "LS"?
I mean obviously that's not the stock coil rail used in an 00 XJ (and 00-06 TJ), but what's the advantage and how difficult was the conversion.
I believe that one of the guys on here who knows his shi1 described the system as firing 2 cylinders per cycle - the normal combustion one plus another for emissions reasons and the coil pack design was essential in this - so assuming that conversion maintains that function, I would believe the wiring stuff would have been a bit of a bi1ch.
Inquiring minds want to know!
I also must assume that this upgrade would be a much bigger deal to do on a pre 00 XJ if not impossible.
I mean obviously that's not the stock coil rail used in an 00 XJ (and 00-06 TJ), but what's the advantage and how difficult was the conversion.
I believe that one of the guys on here who knows his shi1 described the system as firing 2 cylinders per cycle - the normal combustion one plus another for emissions reasons and the coil pack design was essential in this - so assuming that conversion maintains that function, I would believe the wiring stuff would have been a bit of a bi1ch.
Inquiring minds want to know!
I also must assume that this upgrade would be a much bigger deal to do on a pre 00 XJ if not impossible.
Old fart with a wrench
Joined: Nov 2010
Posts: 14,398
Likes: 740
From: Manlius, east of Syracuse, NY
Year: 2000 XJ Sport & WJ Laredo
Model: Grand Cherokee (WJ)
Engine: 4.0L
The original coil rail system operates on the "waste spark" principle whereas 2 cylinders fire every revolution, one on compression and one on exhaust. There are only 3 coils in the rail and 3 drivers in the PCM. It would be a quite simple matter to wire the GM LS coils in pairs to serve the same function. 1&6 fire together, 5&2, 3&4. Obviously the LS coils would fire hotter and last longer than the Jeep system because the rail has a habit of shorting internally.
I really like your idea! I guess you don't need a heater in Venezuela.
BTW, LS is the new generation of Chevy small block engines.
I really like your idea! I guess you don't need a heater in Venezuela.
BTW, LS is the new generation of Chevy small block engines.
Last edited by dave1123; Nov 10, 2019 at 06:33 PM.
CF Veteran
Joined: Jan 2017
Posts: 3,402
Likes: 394
From: Connecticut
Year: 2000
Model: Cherokee (XJ)
Engine: 4.0
CF Veteran
Joined: Jan 2017
Posts: 3,402
Likes: 394
From: Connecticut
Year: 2000
Model: Cherokee (XJ)
Engine: 4.0
Newbie
Joined: Apr 2022
Posts: 7
Likes: 0
From: Las Vegas Nv.
Year: 1989
Model: Cherokee (XJ)
Engine: 4.0 in line 6
It's been 4 weeks now and I'm done. I'm either gonna take it to a shop or put a carb on it. Here's the break down...
92 Cherokee Laredo 4.0.
History...
Fully rebuilt the engine two months ago so the engine itself is fine.
One month ago I noticed a coolant leak from the bellhousing.
Removed tranny and saw bad freeze plug.
Replaced freeze plug, replaced tranny.
Noticed pinhole fuel leak in hose between fuel pump and fuel filter. Replaced hose and filter.
Problem...
Starts, idles, will NOT rev past 2k rpms. Just spits and pops and gasps.
What I think caused it...
I DID forget to unhook the battery when I started to remove the tranny and the starter arced against the frame.
What I did...
I have replaced the ECU, the crank position sensor, the o2 sensor, the ignition coil, the cap and rotor.
Getting spark out of all six wires.
Fuel pressure test shows 36 to 40 psi at all times.
I tested the TPS and it showed a volt range of .060 to .200. It is supposed to be .200 to 3.80ish.
Bought an Autozone TPS and it read the exact same voltages so I took it back.
Bought an O'Reilly TPS and it read the exact same voltages so I took it back.
While examining the wire harness a frayed wire to the TPS grounded against the manifold and caused the fuel pump to cycle.
I then fixed the frayed wire and now the (original) TPS reads perfect voltages. (.300 to 3.80ish).
Problem as of now...
Will NOT stay running when cold. I have to start it about 15 times before it holds a TERRIBLE clunky idle.
The idle gets better and better until it warms up and idles just fine, but it WILL NOT REV PAST IDLE.
It just clunks and pops out the intake and out the exhaust and acts like it is missing terribly but will NOT rev past 1000k to 1500k.
Stinks to high heaven. Plugs are all fouled.
Removed muffler and can see bright glowing red inside the catalytic converter.
What. In the hell. Do I do now? Please, ANY suggestions whatsoever I will try them all.
Thank you.
92 Cherokee Laredo 4.0.
History...
Fully rebuilt the engine two months ago so the engine itself is fine.
One month ago I noticed a coolant leak from the bellhousing.
Removed tranny and saw bad freeze plug.
Replaced freeze plug, replaced tranny.
Noticed pinhole fuel leak in hose between fuel pump and fuel filter. Replaced hose and filter.
Problem...
Starts, idles, will NOT rev past 2k rpms. Just spits and pops and gasps.
What I think caused it...
I DID forget to unhook the battery when I started to remove the tranny and the starter arced against the frame.
What I did...
I have replaced the ECU, the crank position sensor, the o2 sensor, the ignition coil, the cap and rotor.
Getting spark out of all six wires.
Fuel pressure test shows 36 to 40 psi at all times.
I tested the TPS and it showed a volt range of .060 to .200. It is supposed to be .200 to 3.80ish.
Bought an Autozone TPS and it read the exact same voltages so I took it back.
Bought an O'Reilly TPS and it read the exact same voltages so I took it back.
While examining the wire harness a frayed wire to the TPS grounded against the manifold and caused the fuel pump to cycle.
I then fixed the frayed wire and now the (original) TPS reads perfect voltages. (.300 to 3.80ish).
Problem as of now...
Will NOT stay running when cold. I have to start it about 15 times before it holds a TERRIBLE clunky idle.
The idle gets better and better until it warms up and idles just fine, but it WILL NOT REV PAST IDLE.
It just clunks and pops out the intake and out the exhaust and acts like it is missing terribly but will NOT rev past 1000k to 1500k.
Stinks to high heaven. Plugs are all fouled.
Removed muffler and can see bright glowing red inside the catalytic converter.
What. In the hell. Do I do now? Please, ANY suggestions whatsoever I will try them all.
Thank you.
