What is EVO?

[JMDigital]

Ok my power steering fluid is leaking. I found out today that is is the Rack&pinion that is leaking and I need to replace it. When ordering the part I was asked if it has EVO or not. I dont know what that is ?

Thanks for the help.. Oh my the way I am told the part is $400.00 and its a 5week special order... can you let me know if I am getting shafted :1zhelp:

 

[GotBoost?]

Your power steering fluid is leaking from where: high pressure PS hose, the bellows, pump, etc? It's very possible the PS rack costs $400. More or less, depending on what store is ordering your part. If $400 includes the part and installation, that's a fair price. Btw, if the PS rack is leaking, it usually loses all its fluid in a matter of seconds, fyi.
The high pressure hose doesn't even cost $100, plus install. It goes bad from heat, pressure and age. When the high pressure goes bad, the system loses oil much more slowly.
I don't know what they're calling EVO, but some Supras have variable effort PS systems. Maybe that's what they're talking about.

 

[SupraDerk]

Btw, if the PS rack is leaking, it usually loses all its fluid in a matter of seconds, fyi.

Nooooooooot true. My rack leaked and it took a full day for the fluid to completely leak out.

The 89+ I guess had an option, not sure if it was standard or not. They had PPS (progressive power steering) which used a PPS ECU to "dumb" the rack down at higher speeds. That might be what EVO is.

 

[rumptis]

I have an 89 and I have thought it had speed sensitive steering but wasn't for sure...I didn't notice it until I got my speedo fixed and it steering felt completely different afterwards.

 

[mkIIIman089]

^ ah hah, maybe thats what that speed signal off the speedo is used for! I've been trying to figure it out for a while now.

 

[3p141592654]

PPS was on all 89+ supras in north america.

 

[rumptis]

cool...I wish I had a windows stick for my car.

 

[JMDigital]

Arg.. so I need to put fixing the spedo a little higher on the list.. It seems it does alot more then tell me to slow down..

I dont know exactly where its leaking from but the mechanic is a friend and I trust him.

 

[GotBoost?]

Nooooooooot true. My rack leaked and it took a full day for the fluid to completely leak out. QUOTE]

When my rack was leaking, it would loose all its fluid in about 200 yards. Yeah, that's a massive leak. I guess it depends on where the leak is at.

 

[mkIIIman089]

It's used for a lot of things Colin. The ISC system uses it, it's used to calculate deceleration fuel cut off and resumption, cruise control, TEMS, ECT functions and more. Driving around with no speed sensor input effects a lot, especially regarding EFI operation.

Thats pretty interesting. I was always under the impression that most of that stuff was calculated simply by RPMs... Thanks!

 

[supra90turbo]

EVO actuator is GM's term for PPS.
All pumps I have ever ordered for customers that have variable assist or whatever gm likes to call it has specified "Must transfer original EVO actuator to new pump"