Ground Problem?
Thread Starter
Racer
Joined: Feb 2006
Posts: 269
Likes: 0
From: Vancouver B.C.
Ground Problem?
('95 LT1 383)
Code: H21 (TPS)
Voltage reading way low (.32 - 3.7) although the book says code 21 is voltage too high?? Inspected (accessable) wiring to PCM, all look fine. Replaced TPS w/new.....same low reading.
Wiper ground problem as well. Had to ground it out (ground wire to block) in order to work.
Also, Cruise Control not working, although have yet to diagnose that.
This all happened suddenly after a 4 month storage. (everything worked last fall and TPS was at .54 idle) So, I suspect a ground issue in my PCM? Checked/cleaned all the 'known' grounds (7 wire bundle from harness to engine) as well as ground strap from chassis to block.
All to no avail. Still pulling code 21, still failing sniffer (high HC's - rich) still seems to run excellent.
Any suggestions?
Code: H21 (TPS)
Voltage reading way low (.32 - 3.7) although the book says code 21 is voltage too high?? Inspected (accessable) wiring to PCM, all look fine. Replaced TPS w/new.....same low reading.
Wiper ground problem as well. Had to ground it out (ground wire to block) in order to work.
Also, Cruise Control not working, although have yet to diagnose that.
This all happened suddenly after a 4 month storage. (everything worked last fall and TPS was at .54 idle) So, I suspect a ground issue in my PCM? Checked/cleaned all the 'known' grounds (7 wire bundle from harness to engine) as well as ground strap from chassis to block.
All to no avail. Still pulling code 21, still failing sniffer (high HC's - rich) still seems to run excellent.
Any suggestions?
Last edited by Carpenter; Jun 4, 2007 at 04:54 AM.
Intermediate
Joined: Oct 2006
Posts: 39
Likes: 0
From: Memphis TN
Dirty armature ground inside your alternator. I bet you think I'm crazy, pull it apart and look. To get the brushes back in, drill a tiny hole (there may be one already there) in the housing big enough to slide a piece of wire in to hold them back, once the armature is back in place remove the retaining wire to release the brushes.
