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Disconnected Power Steering Pressure Switch causing low idle???

JohnHoward

CEG'er
Joined
Sep 22, 2003
Messages
54
Location
Wisconsin, USA
Can a disconnected Power Steering Pressure Switch (PSPS) cause a bad/low idle?

I'm asking because the wires to my PSPS are broken off and I got a 519 error code ("PSPS not operated during test"). But I assumed that could have nothing to do with a low idle and who needs a PSPS anyway?

BUT in reading the Haynes book just now (6-12) under #10 for "Power Steering Pressure Switch" it states: "...a pressure-operated switch...contacts normally closed, opening when the system reaches the specified pressure. On receiving this signal, the PCM INCREASES THE IDLE SPEED, to compensate for the additional load on the engine."

While I was blaming the IAC, could this disconnected PSPS be causing my low idle?

Of course I will connect it as soon as I can find suitable size connectors and figure out which wire goes where. Any help on this? There are three wires (yellow/purple; white/purple; and brown/white). I can see the male terminals where they attach but the female plug end is missing. All I have are the three broken off wires.

Which color wire goes to which terminal?

Excuse me for starting a new thread, but this may change everything in troubleshooting this problem. The guy who said don't blame the IAC so soon might be right. I hope he is right!

Do you guys think a disconnected PSPS would cause a low idle condition? And to which terminals do the three wires go?

Thanks!!!
 
Progress on PSPS made.

Plug was missing from PSPS. Where could it be? Years ago I wanted to fix it but never did. Figured it was lost for good, but finally found it on back seat floor of the car. Good thing I never clean my car!

Haynes wiring diagram shows a different switch with only 2 wires while my PSPS has 3 wires. But then I thought maybe I had made a note of the plastic (now gone) on the broken wire ends on the plug before messing with it. So I looked in an repair notebook for my old junk and found it! #1: Brown/white #2: White/blue #3: Yellow/violet. Good thing to keep notes.

I then broke off some of the plastic plug end to expose more of the broken wiring. I think that I can solder short pieces of new wire to the old broken ends and then solder the repaired plug unit into the wiring harness. Easier than soldering the broken plug directly into the harness.

I feel pretty confident this may cure my low idle condition, but I feel like an idiot for ignoring that 519 error code and the broken wires to the PSPS and not even mentioning it. But other things came up and I didn't think the PSPS needed to be there anyway because I grew up with carburettors and ignition points, but I'm seeing now that every sensor input affects the driveability of the car. Who'd of thunk it? $50 for a new unneeded IAC is a cheap lesson to how to troubleshoot these modern vehicles -- if this fix works.

Oh yes, I also put all the plastic intake parts back on. Those sure are rinky-dink metal snaps on the air cleaner cover. One smart thing I did was NOT take off the old IAC before I had the new one in hand. I'd feel even more stupid if I had...

Thanks!
 
I should know later today....

I should know later today....

More progress.

Yesterday I carefully soldered 3 short wire lengths to the old PSPS plug. It was a delicate operation because the wire stubs on the plug were very short. But I took my time and it came out okay. Then I used shrink tube to insulate the bare sections of wire.

Later today I will put it into the car and temp. hook up the wires and start the motor just to see if it fixes the low idle condition. I'm pretty confident it will, but have been fooled in the past. If it does fix it, I'll send back the new IAC and order a new 02 sensor which was another code I got.

I just wonder if the PSPS wires will stick up so high they get smashed when the hood comes down. They are mounted very high. I'm thinking that's what broke them off before.
 
yes the sensor effects idle. when it senses pressure the pcm will bump the idle up as not to create to much drag from the ps pump at idle.
 
yes the sensor effects idle. when it senses pressure the pcm will bump the idle up as not to create to much drag from the ps pump at idle.

And that appears to be true for my Contour too!

I hooked up the wires and with the PSPS attached the car idled better than before. It still seemed to idle kind of low, but it did not kill or run rough and "chug" like before. But that was just up on ramps for a minute. I'll solder the wires in tomorrow and take it out for a test drive. That should tell me more.

02 sensor next up.

Thanks!
 
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