Adjusting the TPS

[Trevor]

Originally Posted by svxfiles

Hi Trevor.

When you hook up a Subaru Select Moniter you have four modes to check out your SVX.
The first that pops up is EGI, to check the engine parameters
then AT for information on the automatic transmission,
AC for checking out the air conditioning stuff,
and CC for the cruise control.

On the engine mode you can check the vehicle speed in both MPH or KPH.

But in the trans mode you can check either speed sensor #1, or #2,
in both MPH and KPH.

In EGI and AT you can check engine temp, in both farenheit and celsius,
and THOSE readings show the same...

More later.

(1) Exactly how did you produce/create two actual specific parameters, when you took the two different and separate TPS voltage readings quoted?

(2) Was a select monitor connected?

(3) Was the engine running?

(4) What in fact actually changed between taking the two readings of 0.48 and 0.5 volts?

As Joe has noted this is interesting information and is worth pursuing.

[svxfiles]

Originally Posted by Trevor

(1) Exactly how did you produce/create two actual specific parameters, when you took the two different and separate TPS voltage readings quoted?

(2) Was a select monitor connected?

(3) Was the engine running?

(4) What in fact actually changed between taking the two readings of 0.48 and 0.5 volts?

As Joe has noted this is interesting information and is worth pursuing.

(1)

(2) Yes.

(3) Yes, or key on and not running.

(4) I switched between the modes without touching/adjusting/moving anything else.

I can only assume that there is more resistance in the AT testing circuit, as this happens on almose every SVX that I check.

Please note that Subaru says anything between 0.45 and 0.55 is within specifications.
I only share my experiences to help.

[svxfiles]

Originally Posted by ridered777

Seems like SOMEONE is having fun playing with his toy...

Yes.

Another fun thing is driving around and watching the timing advance, watching the boost gauge, watching the timing retard, watching the boost gauge, watching the wide band readings, watching the boost gauge, and on occasion, watching the ROAD!!!


Oh look, a birdie!

[svxfiles]

Originally Posted by svxistentialist

He's rubbing it in Craig, just 'cos the rest of us don't have one!!

OK,ok, NOW^ I was rubbing it in!
















MMMmmmmmm, BOOST!

[ridered777]

Originally Posted by svxfiles

Yes.

Another fun thing is driving around and watching the timing advance, watching the boost gauge, watching the timing retard, watching the boost gauge, watching the wide band readings, watching the boost gauge, and on occasion, watching the ROAD!!!


Oh look, a birdie!

We can all have our fun...

Wait, wait, wait. You have BOOST?! EDIT: Oh my, look at your siggy... guess you do! I didn't know that. I guess because I only ever here YT and Bobby talking about their boost woes, or what their next thing is in relation to boost...

Aren't you too old to be paying attention to all those things at once?! EDIT: Aren't you too old for boost too?! :P

Hahah. Just kidding!

And yes Joe, he is rubbing it in. Thoroughly. Next thing we know, we'll have Earl in here talking about all the SVXi he owns, and how its such a PAIN to find time to drive ALL of them...

[svxfiles]

Originally Posted by ridered777

We can all have our fun...
Aren't you too old to be paying attention to all those things at once?! EDIT: Aren't you too old for boost too?! :P

lol:

I just looked at YOUR signature, young man!, Now GO CLEAN YOUR ROOM!!!




























No, seriously, go clean your room!











"Or are you talking vacuum/pressure(boost) in the manifolds?"

Crazy kids!

[Manarius]

Well, I adjusted the TPS to exactly .50v DC.

Still have cold hesitation. *sigh*

[Manarius]

Hate to bring this one back up again, but I took a video of some of the hesitation I have when cold. The TPS is adjusted to exactly .50v.

http://www.youtube.com/watch?v=9Efjxpy4DYc

I still think there are others who could benefit from tracking this problem down (including myself).

I liken it to awakening the sleeping beast. The car when it gets to a certain temperature seems to awaken from being hesitant to want to go. It also seems to be RPM dependent as well, but who knows. It certainly seems electronic however.

[Trevor]

Jason,

Firstly, did you remove and test the TPS as per my how too stuff?

Idle speed is directly dependant on the TPS, the Auxiliary Air control valve and the By-Pass Air Control Solenoid Valve, as well as engine speed sensing. The AACV is temperature sensitive and is suspect as you report all is OK when the engine warms up.

I could do a write up on what is involved but this would no doubt provoke further sarcastic comment, that I simply copy and paste the information which I provide. I now refrain from this activity, in view of official instruction that I have no means of even mildly robust recourse, against such insults.

[Ricochet]

Originally Posted by Manarius

http://www.youtube.com/watch?v=9Efjxpy4DYc

I'm no mechanic but that doesn't sound too good.. just let it warm up before driving I guess?

[Manarius]

Originally Posted by Trevor

Jason,

Firstly, did you remove and test the TPS as per my how too stuff?

Idle speed is directly dependant on the TPS, the Auxiliary Air control valve and the By-Pass Air Control Solenoid Valve, as well as engine speed sensing. The AACV is temperature sensitive and is suspect as you report all is OK when the engine warms up.

I could do a write up on what is involved but this would no doubt provoke further sarcastic comment, that I simply copy and paste the information which I provide. I now refrain from this activity, in view of official instruction that I have no means of even mildly robust recourse, against such insults.

The TPS is brand new. I didn't remove it because it was brand new.

Idle is fine. However, the AACV may be suspect here as you said. Is the AACV what we call the Idle Air Control Valve? I guess I can test that next.

[Trevor]

Originally Posted by Manarius

The TPS is brand new. I didn't remove it because it was brand new.

Idle is fine. However, the AACV may be suspect here as you said. Is the AACV what we call the Idle Air Control Valve? I guess I can test that next.

There are two valves which control air supplied at idle in respect of the SVX, i.e. “Idle Air Control Valves” and hence confusion. From what I have seen. the By-Pass Air Control Solenoid Valve, is the one often referred to as an an Idle Air Control Valve, IACV.

The AACV is not electrically operated, being directly activated by temperature. The BPACSV incorporates a rotary solenoid, as per my write up. This valve could also be involved as it is operate by the ECU, which does have an input based on engine temperature. However in your as reported case, the BPACSV is second in the chain of suspect items, IMHO.

[Manarius]

Originally Posted by Trevor

There are two valves which control air supplied at idle in respect of the SVX, i.e. “Idle Air Control Valves” and hence confusion. From what I have seen. the By-Pass Air Control Solenoid Valve, is the one often referred to as an an Idle Air Control Valve, IACV.

The AACV is not electrically operated, being directly activated by temperature. The BPACSV incorporates a rotary solenoid, as per my write up. This valve could also be involved as it is operate by the ECU, which does have an input based on engine temperature. However in your as reported case, the BPACSV is second in the chain of suspect items, IMHO.

So what exactly is the AACV? I don't think I have found your write up regarding exactly how to deal with the AACV. Diagrams would be helpful.

Thanks.

[Trevor]

Originally Posted by Manarius

So what exactly is the AACV? I don't think I have found your write up regarding exactly how to deal with the AACV. Diagrams would be helpful.

Thanks.

Sorry Jason, I have not done a write up on the AACV, only on the AACSV.

The AACV supplies extra air when the engine is cold. It incorporates a bimetal strip as the active component, This is heated by an element so as to bend and operate a rotary air valve. The inlet and outlet passages are opposite each other and if the flexible tubes are removed, it should be possible to observe the valve, which is directly between the two, as being open or closed.

It is appreciated that all of this is difficult, as nothing involved is at all easy to get at.

[redlightningsvx]

Ok, briging this up because of recent sucky slowness action at the drag strip. I adjusted the tps to .48 volts an the idle is set 1 tick below 1000rpms. Then when the fans kick on the tps reads .401-3 volts, and when the fans quit running it goes back to .48 volts. Just want to know if this is normal. Also i'm getting a code 31 for the tps and it will not clear.