New user needs help
Thread Starter
6th Gear
Joined: Sep 2023
Posts: 6
Likes: 2
From: Clarks Summit ,PA.
New user needs help
I have an 1998 C5
codes I pulled P1221
P1120
P1221 returns immediately when I try to reset it
" Reduced engine power" " Service traction system" " Service active handling"
it all started unexpectedly today after I drove home ...I cleaned all grounds and plugs on intake ( TBS,MAF cleaner, PCM, TAC plugs etc)
tried my best before bothering you all ......any ideas ? all grounds looked good actually even the ones by the headlights I took the box apart and the insides were shiny new on both sides of car ..
codes I pulled P1221
P1120
P1221 returns immediately when I try to reset it
" Reduced engine power" " Service traction system" " Service active handling"
it all started unexpectedly today after I drove home ...I cleaned all grounds and plugs on intake ( TBS,MAF cleaner, PCM, TAC plugs etc)
tried my best before bothering you all ......any ideas ? all grounds looked good actually even the ones by the headlights I took the box apart and the insides were shiny new on both sides of car ..
Last edited by theski00; Sep 13, 2023 at 05:45 PM.
Melting Slicks
Joined: Sep 2008
Posts: 3,117
Likes: 793
From: Espanola New Mexico
If proficient with DMM measure across battery terminals should be around 12.5v for a fully charged battery. You could disconnect the negative battery cable for 5- 10 minutes and reconnect that sometimes clears the codes.
Thread Starter
6th Gear
Joined: Sep 2023
Posts: 6
Likes: 2
From: Clarks Summit ,PA.
Hello...yes I did that on battery...... battery was in the green good mark ( lower green) when I put my burner tester on it ....I'm going to get a new battery tomorrow and a new alternator...( it has been a little fluctuating in volts as I drive from 12.3 to 14 volts ( but mostly is at 13.8 volts) but I've been meaning to replace both for good measure and ....I ordered a TPS sensor as well
Le Mans Master
Joined: Mar 2002
Posts: 8,466
Likes: 51
St. Jude Donor '17
Thread Starter
6th Gear
Joined: Sep 2023
Posts: 6
Likes: 2
From: Clarks Summit ,PA.
Got it
Well I took apart the TPS sensor hair dryered it put it back together and now everything is fine. There was water in it. Also. All codes are gone the reduced power is gone etc etc wish me luck 
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