Need Help. On Vacation and motor is going NUTS!!!
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Teching In
Joined: May 2017
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Need Help. On Vacation and motor is going NUTS!!! Info: 02 2500 LQ4 swapped into a Jeep Wrangler. Flipped it last year. Parked for about 4 months while overhauling suspension. EGR deleted along with rear O2 sensors.
Problem: Falling flat on acceleration and cruising. WOT runs like a raped ape. Sometimes while driving it will correct and run great. But only for seconds. Then back to a bog.
At idle it sounds great. Fuel pressure is around 55. On throttle it jumps to 60. I've replaced all the plugs. MAF is 4 months old and cleaned. Pulled codes and it showed a knock sensor issue. Pulled the intake and replaced both knock sensors and harness. Went ahead and replaced the intake with a cleaner one. While in it I cleaned the TB really well. Fired it up and thought we had it whooped. No dice. After driving down the road it is back. All the coils are firing.
I hooked it up to a Snapon scanner and the only thing it is showing is an O2 sensor reading on the passenger side that is all over the place. From 200 to 800. Constantly bouncing. I plan on changing this out tomorrow. If this doesn't fix it, where should I look next? I filled it with premium and threw a can of seafoam in it, hoping it would help.
Any help would be greatly appreciated.
Problem: Falling flat on acceleration and cruising. WOT runs like a raped ape. Sometimes while driving it will correct and run great. But only for seconds. Then back to a bog.
At idle it sounds great. Fuel pressure is around 55. On throttle it jumps to 60. I've replaced all the plugs. MAF is 4 months old and cleaned. Pulled codes and it showed a knock sensor issue. Pulled the intake and replaced both knock sensors and harness. Went ahead and replaced the intake with a cleaner one. While in it I cleaned the TB really well. Fired it up and thought we had it whooped. No dice. After driving down the road it is back. All the coils are firing.
I hooked it up to a Snapon scanner and the only thing it is showing is an O2 sensor reading on the passenger side that is all over the place. From 200 to 800. Constantly bouncing. I plan on changing this out tomorrow. If this doesn't fix it, where should I look next? I filled it with premium and threw a can of seafoam in it, hoping it would help.
Any help would be greatly appreciated.
Originally Posted by Fireman Crawler
Driver's side was moving from 925 to 975.
Sensor should bounce from 200-800 like crazy.
When you hit WOT, it ignored oxygen sensors and fuels according to tables. "Open loop".
Light acceleration and cruising, if sensor is always reading 900+, the computer tries to keep cutting fuel. 450 is stoich. Higher is rich, lower is lean. The ECU expects it to switch rich to lean to rich to lean constantly.
