1999 GS300 Limp Mode
Thread Starter
Driver School Candidate
Joined: Feb 2019
Posts: 6
Likes: 0
From: NJ
1999 GS300 Limp Mode
Good evening everyone!
My name is Nick, and I have a 1999 Lexus GS300. I recently completed the W58 Manual Swap, and now I'm having engine trouble.
I'm running a stock 2JZGE, and it is in limp mode. The vehicle won't rev past 4000 RPMS, and at idle its extremely shaky. It will be steady at 1200, then drop down or move up by itself. Sometimes out of nowhere it will jump to 2000 by itself and stay there.
List of things I have replaced -
Spark Plugs
Coils and wires
Throttle Position Sensor (TPS)
Mass Air Flow Sensor (MAF)
VVT-i Oil Control Valve (OCV)
Oxygen Sensors
I insured there are no vacuum leaks whatsoever.
There are 9 trouble codes, all related to a missing automatic transmission. Nothing engine related.
I'm about ready to buy a used TB and see if that helps.
Any info or leads would be fantastic. Thank You all.
My name is Nick, and I have a 1999 Lexus GS300. I recently completed the W58 Manual Swap, and now I'm having engine trouble.
I'm running a stock 2JZGE, and it is in limp mode. The vehicle won't rev past 4000 RPMS, and at idle its extremely shaky. It will be steady at 1200, then drop down or move up by itself. Sometimes out of nowhere it will jump to 2000 by itself and stay there.
List of things I have replaced -
Spark Plugs
Coils and wires
Throttle Position Sensor (TPS)
Mass Air Flow Sensor (MAF)
VVT-i Oil Control Valve (OCV)
Oxygen Sensors
I insured there are no vacuum leaks whatsoever.
There are 9 trouble codes, all related to a missing automatic transmission. Nothing engine related.
I'm about ready to buy a used TB and see if that helps.
Any info or leads would be fantastic. Thank You all.
Rookie
Joined: Feb 2019
Posts: 50
Likes: 2
From: FL
I had an issue where my 05 GS would bog down as if the MAF was not reading right, it turned out that the last catalytic converter was clogged, my MAF reading was 2g/s lower than what it should have been at idle when the cat was clogged.
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Rookie
Joined: Apr 2016
Posts: 61
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From: Georgia
Thread Starter
Driver School Candidate
Joined: Feb 2019
Posts: 6
Likes: 0
From: NJ
The throttle body was off the engine because I just finished swapping in a new low mileage one along with the manual transmission. If I take off the air snorkel and look in I can see the throttle blade move and function as it should as I move the lever. Although I'm getting this weird noise coming from it. Sounds electrical. I'm going to swap in a different TB and see what happens.
Again, there's no codes and I've changed the MAF. I'm getting 12volts to it from the ECU. Although the fuel light is flashing fo some reason.....maybe it's fuel cutting?
Again, there's no codes and I've changed the MAF. I'm getting 12volts to it from the ECU. Although the fuel light is flashing fo some reason.....maybe it's fuel cutting?
Thread Starter
Driver School Candidate
Joined: Feb 2019
Posts: 6
Likes: 0
From: NJ
I'm just really confused because it starts right up but the idle is NEVER consistent. It'll drop then go up and down and sounds like it wants to die but then jumps to 2000 and stays there. It's so weird.
Ive had the multimeter out for the past couple days, I've traced back the harness and nothing is grounding out. Not sure what else to look for at this point.
Ive had the multimeter out for the past couple days, I've traced back the harness and nothing is grounding out. Not sure what else to look for at this point.
Intermediate
Joined: Jul 2017
Posts: 266
Likes: 44
From: Florida
The intake snorkel.. squeeze it makd sure no hidden rips.
If memory serves well, recently on thd forum someone had issues solved when putting back thd original intake tubing as hd had changed to larger diameter and caused ptoblems.
Ill look around the board see if i find it.
If memory serves well, recently on thd forum someone had issues solved when putting back thd original intake tubing as hd had changed to larger diameter and caused ptoblems.
Ill look around the board see if i find it.
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lildorsey1
GS - 2nd Gen (1998-2005)
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Jan 2, 2015 01:27 PM