Scan Master Reading - is the tuning way off?

[PsYcHo GN]

I bought my Scan Master a few months ago, but never paid too much attention to the numbers because the car was running fine. Now that I've completely finished the alky install tonight, I took it for a test drive and these are my Scan Master numbers at idle (average):

o2 640
AF 04
L8 34
bat 13.5
Int 128
bL 133
mph 00
Clt 171
Ats 72
r 825
tps .50 (always stays at .50)
IAC 07
cc 33
mal 00

What looks good and what looks bad? What needs to be adjusted and how?

Thanks in advance for the info!

One more thing... when I go to 'Recall' mode, it doesn't go into recall mode because it's not going into 'Record' mode. Even if I drive the vehicle around at WOT.

 

[PsYcHo GN]

{{{{Anyone???}}}}

 

[johnnyttype]

everything is pretty good for the most part. i would bump the iac counts at idle in park up to about 15-20 counts. sounds like maybe ur TPS sensor is bad. ur car will not go into record mode unless the tps sensor registered above 3.0 volts. i think u can test the sensor with an ohm meter. car off, unplug connector and take a look at the wires. shoud be three since it is a variable resistor. dont know colors off hand but i imagine that there will be a black wire for ground, go across the other two on the sensor and see if the ohms readings change, go up and down with throttle movement. u could do same test with key on and backprobe connector when plugged in to measure voltage instead of ohms! i think i typed that all eight! hth

 

[TurboDave]

Turn your key on without starting the engine. Slowly press the throttle down to WOT while monitoring tps on the Scanmaster. Does it move to higher values when you press the pedal? or does it always stay at .50 (too high for idle value anyway)? If it doesn't follow your pedal then replace it before driving anymore.
The rest of your numbers look pretty good except for a low AF reading. Should be 06 +/- nor more than 1.

Which maf? 3" or 3.5"? What's the MAF BASE setting in your Translator?

I would imagine the reason it doesn't record is because your TPS is shot. Scanmaster needs to see the TPS go WOT before it can record values.

 

[PsYcHo GN]

Turn your key on without starting the engine. Slowly press the throttle down to WOT while monitoring tps on the Scanmaster. Does it move to higher values when you press the pedal? or does it always stay at .50 (too high for idle value anyway)? If it doesn't follow your pedal then replace it before driving anymore.
The rest of your numbers look pretty good except for a low AF reading. Should be 06 +/- nor more than 1.

Which maf? 3" or 3.5"? What's the MAF BASE setting in your Translator?

I would imagine the reason it doesn't record is because your TPS is shot. Scanmaster needs to see the TPS go WOT before it can record values.

I'll have to try tps when I get home this evening.

I'm running the 3.5" MAF and the Base and WOT settings are at "0"

How do I adjust the AF settings?

Thanks!

 

[TurboDave]

I'll have to try tps when I get home this evening.

I'm running the 3.5" MAF and the Base and WOT settings are at "0"

Try setting "1" (a little richer).

How do I adjust the AF settings?

You can't, at least not directly. MAF settings will have some small affects.

 

[PsYcHo GN]

Try setting "1" (a little richer).



You can't, at least not directly. MAF settings will have some small affects.

I set the "Base" setting of my translator to "1" and now the AF is around 6-8

I also tried the throttle with the ignition ON and the "tps" setting does increase. When I start the car, the "tps" is at .50 and doesn't change.

Is there a way to adjust it for a lower reading? I ordered a new TPS through the dealer, but they're not sure if they've been discontinued, so they will contact me when they find out.

 

[johnnyttype]

does the tps. voltage move with the car on and u giving it throttle input? .50volts is too high for idle. u want it to be below .42. u can loosen the two screws on the sensor, it has slotted holes for adjustment. with key on engine off set idle to .40 or so and then set WOT at 4.4volts or higher if it will let. this procedure will be annoying if its ur first time because every time u adjust one parameter the other will jump out of spec. hth! ttt

 

[PsYcHo GN]

does the tps. voltage move with the car on and u giving it throttle input? .50volts is too high for idle. u want it to be below .42. u can loosen the two screws on the sensor, it has slotted holes for adjustment. with key on engine off set idle to .40 or so and then set WOT at 4.4volts or higher if it will let. this procedure will be annoying if its ur first time because every time u adjust one parameter the other will jump out of spec. hth! ttt

I had it on Ignition ON (engine off) and I was looking at the values on the Scan Master and the values kept increasing as the throttle was going down. I figured the tps sensor is working, so I started the car and the tps value would not change from .50

If I loosen the two screws on the sensor, how do I set the idle? Is there an adjustment screw?

 

[TurboDave]

I'm still a little confused about whether you're saying it's working or not.

With key on, engine off, you press the acclerator all the way to the floor, what does the TPS value show with the acclerator on the floor?

 

[54Rich]

I just did this last week. Takes about 15 min at the most:

IAC Reset Procedure

Then:

Adjusting the TPS

While your there might as well make sure this is right:

TV Cable System

Made a big difference in my car, settings were way off

Rich

 

[TurboDave]

OK, I think I see now. It does increase with throttle pressing.

You just need to go through the TPS adjust procedures to get the idle value close to .40-.42 (ideal values). WOT close or over 4.6

That IAC reset procedure (good procedure) that 54Rich points to is a good one that Ken and I collaborated on years ago, but because of what he named it, it often get confused with the reset procedure that actually resets the IAC motor (bad procedure).
I wish Ken would have named it what it actually is, and that is IAC adjustment procedure.

 

[johnnyttype]

I had it on Ignition ON (engine off) and I was looking at the values on the Scan Master and the values kept increasing as the throttle was going down. I figured the tps sensor is working, so I started the car and the tps value would not change from .50

so it works when engine off but does not move no matter what u do when engine is turned on? do i have this right? sorry its alittle early

if i have it right it sounds like the signal is droppin out when the car is strated. do u have anything like a volt booster on the car? oh and what is the max WOT voltage u get with the engine off, i think someone asked that earlier?

 

[PsYcHo GN]

so it works when engine off but does not move no matter what u do when engine is turned on? do i have this right? sorry its alittle early

if i have it right it sounds like the signal is droppin out when the car is strated. do u have anything like a volt booster on the car? oh and what is the max WOT voltage u get with the engine off, i think someone asked that earlier?

Yes, when the engine is OFF, the tps values increase. At full throttle, I think it was at 1.46

I don't know what a volt booster is. I will try to adjust the tps over the weekend and see if I can lower the numbers. I will replace it when the new part comes in.

So the AF increased a couple of values. Now I just need to get the tps numbers correct and everything should be good, right?

 

[johnnyttype]

yea, 1.46 is way low for WOT. once u get the new sensor and set it to the specified parameters everything should be in working order. ur scanmaster will be able to see the needed voltage to start recording with the new sensor.

oh, the volt booster, ive just seen people with sensors issues when they install a volt booster harness and when they disconnect it goes away. if u dont have one then no need to worry!

 

[TurboDave]

Yes, when the engine is OFF, the tps values increase. At full throttle, I think it was at 1.46

I don't know what a volt booster is. I will try to adjust the tps over the weekend and see if I can lower the numbers. I will replace it when the new part comes in.

So the AF increased a couple of values. Now I just need to get the tps numbers correct and everything should be good, right?

Don't bother trying to adjust the TPS. Based on what you just said it sure sounds like you have a bad TPS.

You can make a quick check by trying to get the full throttle value higher.
Loosen both screws holding the tps in place just enough to allow you to move it. Pull it as far forward toward the front of the car as the slots will allow, tighten them. With key on, engine off, go to full throttle.
Does the value exceed 4.0 volts? If not, go no further, and replace the tps.

 

[VadersV6]

Dont make assumptions guys. He may not be getting to full throttle.
First, check that. Pop the up-pipe off. Have someone sit in the car and go to wide open throttle. Look to see if the throttle blade is opening all the way. If it doesnt, then your TV cable is probably screwed up or something is jammed. Do the TV cable adjustment on gnttype.org. Its real easy.
Next step is to adjust the IAC stepper motor/idle air bypass. Follow the procedure on gnttype.org. Make sure the engine is completely warmed up when you do it or the numbers will change.
Once thats dialed in,
Loosen the TPS screws just barely enough so that the sensor stays tight but you can rotate it.
Pull the sensor toward the front of the car..this will get you more "sweep". Rotate it slowly until the voltage says .42 volts. Tighten the screws down and check again. Keep going till its .42, locked down with the engine idling. It shouldnt change just idling...but it may move like .01 volts as the engine vibrates. Thats normal.
Now with the ignition on, slowly give it more and more throttle, and look at the tps number on your scanmaster, and make sure the number keeps rising, with no points where it doesnt respond, or goes dead or changes in a random direction. It should sweep up to at least 4.3 volts. Some people's tps goes up to 4.8, but as long as you're getting true wide open throttle and getting above 4 volts, you're fine.
The tps is a variable potentiometer...like a speed knob for electric motors or a light dimmer in your house. The voltage output changes as you rotate it. Its a variable resistor basically. It uses voltage instead of a quadrature signal like an encoder on modern day stuff (overlapping square waves...they're used for position sensing on all sorts of machines). If the number is always the same at WOT and always the same at closed throttle no matter how many times you cycle it, then its fine.

 

[trbojo]

i noticed you have razor's alky kit, which uses the 5 volt reference wire from the tps for the supplied map sensor. you usually tap off the tps wire and run it to the new map. any chance of a loose/weak/broken connection in this area?

 

[PsYcHo GN]

i noticed you have razor's alky kit, which uses the 5 volt reference wire from the tps for the supplied map sensor. you usually tap off the tps wire and run it to the new map. any chance of a loose/weak/broken connection in this area?

I tapped the gray and black wires from the harness behind the glove box and tapped them into the ECM. The green wire from the MAP sensor is connected to the green input wire on the PAC. I didn't tap any wires from the tps sensor. That was a good point, since most people tap their alky wires off the tps! The tps value has never moved from .50 since I've had my Scan Master (which was before I installed the alky). I think the TPS sensor is probably bad. I order one through the GM dealer and I also ordered one from Gyrhead today. I have a feeling my GM guys can't get it since they're discontinued, but they've found me discontinued items before. They're pretty good guys at Harbor Chevrolet in Long Beach, CA.


I will have to try to adjust the TV cable, TPS sensor, and the IAC as TurboDave and VadersV6 suggested. Hopefully it will work. Regardless, I will replace my MAP sensor when the new one arrives.

 

[PsYcHo GN]

Finally found time to work on my car this evening.

I did the TV Cable Adjustment. Everything went fine.

I did the IAC Reset Procedure and increased the value to 23.

Then I got to the TPS adjustment. I had the Ignition ON (engine off) and got the idle value to .46 and WOT value to 4.5 (this was challenging to get both values within the range).

Once I completed everything, I started the car up to verify the values on the Scanmaster are correct. The IAC was good, but the TPS went back to .50 . When I turn the car off, then the TPS value goes back to .46

When my new TPS sensor comes in, I'll install it and repeat this exercise. Hopefully the new sensor will fix this issue.