STS oil pump????
STS oil pump???? my oil scavange pump only works on high , low speed setting is inop , been told it could be the resistor on wire harness, has anyone replaced one and if so how, it is wired into harness??? 
Joined: Jun 2004
Posts: 1,501
Likes: 7
From: Ft. Irwin, California (But Virginia is home)
Originally Posted by smoke20
my oil scavange pump only works on high , low speed setting is inop , been told it could be the resistor on wire harness, has anyone replaced one and if so how, it is wired into harness???
Couple things could be causing your problem. The resistor does just as the name implies....restricts voltage to the pump during light loads. The two "black boxes" on the wiring harness near the resistor are switches that bypass it to allow the pump to operate at high speed (via unrestricted voltage). Possible one of those is "stuck", but not too likely. The switch connected to the vacuum source by the pcm is a more likely culprit. That is what senses the 1PSI of boost and then sends the signal to the switch to bypass the resistor. Check the wire connections on this. If the wire connection is arcing actoss the pressure switch, it will bypass the resistor and the pump will operate at high speed. If you really think the resistor is bad....check it for heat (but not with your bare fingers
) If the resistor isn't getting hot, then it's being electrically bypassed. If it's smoking hot and everything else checks good....then the resistor might be going bad. If it is failing, it's a common elelctrical resistor. Should be able to get one locally in your area.Probably not the best explanation, but hopefully this helps.
Joined: Jun 2004
Posts: 1,501
Likes: 7
From: Ft. Irwin, California (But Virginia is home)
Originally Posted by smoke20
hey schantin found the problem , the power wire leading to the psi switch had worked itself loose, tightend and now pump works like a champ
