Would code P0121 (TPS) cause built trans not to downshift at WOT? tuning problem?
Thread Starter
TECH Fanatic
Joined: Nov 2001
Posts: 1,064
Likes: 0
From: CA
Would code P0121 (TPS) cause built trans not to downshift at WOT? tuning problem? I am receiving codes:
P0507 - Idle Control System RPM Higher Than Expected
P0121 - Throttle Position Sensor A Circuit Range/Performance
From a dead stop, my built 4L60e trans runs through all 4 gears just fine. But from a 20-40mph roll in second, third and sometimes fourth gear and I go WOT, it hesitates and will not downshift for about 3-5 seconds. The car “wants” to go, it bogs down for this short time – then she shifts and I am on my way.
What else could this be if the TPS is not the issue?
Thanks
P0507 - Idle Control System RPM Higher Than Expected
P0121 - Throttle Position Sensor A Circuit Range/Performance
From a dead stop, my built 4L60e trans runs through all 4 gears just fine. But from a 20-40mph roll in second, third and sometimes fourth gear and I go WOT, it hesitates and will not downshift for about 3-5 seconds. The car “wants” to go, it bogs down for this short time – then she shifts and I am on my way.
What else could this be if the TPS is not the issue?
Thanks
TECH Senior Member
Joined: Nov 2001
Posts: 7,036
Likes: 1
From: Lake Zurich, IL
I'd hook up some sorta scanning tool and see what the TPS % and voltage is during problem times.... (or just use a voltmeter, 4.4 or 4.5 volts is WOT I believe... closed is .5 volts I think ... so just step it up watching to see if thevoltage increases proportionally)
The PCM uses TPS apply percent to determine what speed to downshift at... (as well as upshifting)
The PCM uses TPS apply percent to determine what speed to downshift at... (as well as upshifting)
On The Tree
Joined: May 2003
Posts: 145
Likes: 0
From: New Jersey
Originally Posted by MeanWS6
I am receiving codes:
P0507 - Idle Control System RPM Higher Than Expected
P0121 - Throttle Position Sensor A Circuit Range/Performance
From a dead stop, my built 4L60e trans runs through all 4 gears just fine. But from a 20-40mph roll in second, third and sometimes fourth gear and I go WOT, it hesitates and will not downshift for about 3-5 seconds. The car “wants” to go, it bogs down for this short time – then she shifts and I am on my way.
What else could this be if the TPS is not the issue?
Thanks
P0507 - Idle Control System RPM Higher Than Expected
P0121 - Throttle Position Sensor A Circuit Range/Performance
From a dead stop, my built 4L60e trans runs through all 4 gears just fine. But from a 20-40mph roll in second, third and sometimes fourth gear and I go WOT, it hesitates and will not downshift for about 3-5 seconds. The car “wants” to go, it bogs down for this short time – then she shifts and I am on my way.
What else could this be if the TPS is not the issue?
Thanks
What should the base and WOT TPS voltages be on a 2002 throttle body?
What you need to do is in the Engine Diagnostics section of your editor. Find the tables that read PO121 error min/max. Edit those values to read 85 and 65. I know the trouble that the code has caused. My trans would do some really weird things. Edit those tables if you have the resources and you will be fine.
