athenG

iTrader: (2)

really? I thought I heard your Turbo spool when you reved your engine and before you took of on your video.. Also you cant just rev your car when it is still cold and expect the turbo to spin. On my video my car is already warmed up and been driving for 10 mins already before I took the video.

toddrs93

I don't believe so, its pretty responsive, a nice fit for that motor.

DanielW

iTrader: (27)

Yeah thats one thing about the kit... you've really got to get it warmed up for peak performance. I see it as a trade off for the lower IAT's

Boozt

Any of the STS guys running an ECU reflash????? Looking into to improve peak performance of my STS Z. Feed back would be great- Jim

Ahsmo

iTrader: (13)

Johnny, did you modify the fuel pressure regulator? (not sure if this has been covered) Or did you just drop the walbro in? My idle is wild. This is due to the unstable fuel pressure at idle. The only way to fix it is to modify the regulator or run a fuel return system.

Boozt, The UTEC controls everything at wide open throttle. The stock ECU only controls off boost conditions. So if you want to improve driveability then sure, go for it.

athenG

iTrader: (2)

how wild is your idle and what rpm do you idle? I idle around 700-800 when I let it idle for over 3 mins but when I'm driving I idle around 800-950 when on a stoplight. My idle do drop/increase about 100-200rpm too and dont know if it is my TB going bad. I always thought you need a return system to actually change the fuel pressure with our car..

Ahsmo

iTrader: (13)

It is fluctuates about 3 or 400 RPM I think. I don't really remember. My AFRs go crazy. I idle at 900 rpm. Before I had the idle bumped the car was worse. When Mark at SGP tuned my car it improved some but the fluctuations didn't go away.

According to CJM, unless you drill out the fuel pressure regulator according to the instructions in the Turbonetics manual the fuel pressure at idle is pretty wild with the Walbro. I never drilled it out because it really didn't bother me that much and CJM said it wouldn't hurt anything.

I emailed STS about this problem but they ignored me.

Boozt

Technosquare claims throttle response is better....Plus increased redline, no speed limit, and able to ditch the annoying CEL's. True????

Ahsmo

iTrader: (13)

I am sure there would be some difference in throttle response but it would only be noticeable at partial throttle. I could be wrong but on a NA car this would be very noticeable. What year is your Z? The Utec can bump the redline on some years but it is probably not recommended with the stock block. What CEL's do you have? Only one I get is the misfire code. I bought a cheapo code reader to erase those.

JonnyC

iTrader: (19)

Yeah, I installed the Walbro per phunk's (CJM's) instructions. I didn't have this issue at all with my 650cc injectors and walbro, but I have now switched to 440cc (old Bosch, so really 400cc). My fuel pressure is solid at idle though, although a little high at ~51 psi (if I remember right). But who knows how accurate my gauge/sensor is.

I idle around 650 maybe, then drop down to 500 (I think) and that's where it wants to die. My friend has a Consult II, so I was maybe just going to bump the idle and see if it goes away. However, I don't want to mask a real problem if there is one.

We'll see come this next spring, but thanks for helping me try to diagnose it.

JonnyC

iTrader: (19)

Ahsmo - I just noticed you're selling your kit. Maybe I completely forgot if you stated that before, but what the hell?! It seems as though the STS crowd is diminishing.

JonnyC

iTrader: (19)

The flashers seem to want to sell their flash to anyone and everyone regardless of the situation - at least that's what I've noticed.

I was looking into getting a flash for the simple reason of scaling my injectors on the ECU. You obviously scale the injectors in the UTEC for when it is in control, but there are weird situations when you can feel hiccups (very light throttle after decel). Also, with my 650cc's before, the car had a hard time starting because the UTEC has no control over the injectors while cranking.

Anyways - I emailed UpRev about it, and they said they would need to do a full tune since there's no such thing as a simple reflash to scale the injectors. They then wanted to sell me their $700 flash tool.

Ahsmo

iTrader: (13)

I think you would definitely see an improvement with an idle bump.

Sorry I totally forgot you were supercharged before. Then the obvious conclusion then is that my idle problems may not be due to my fuel pressure. I will find out when I go back to stock and leave the walbro in or take it out. Your problem is obviously related to the kit. Could one of the solenoid valves be leaking by on the PCV system? Again I am not familiar with your PCV setup but...

I don't think I came out and said it but I am going into the Navy and I needed to get rid of this money pit before I got too busy to fix it every time it had a problem. Not that I have had any but I expected the engine to let go in the future. This was a problem I really did not want to worry about while I was in school or moving somewhere. I am going to get another Z and turbocharge it in the next 5 years. For now, the 08 crew cab Silverado I just bought will reliably get me to and from work and carry all of my stuff too. These two things I could not depend on my Z to do for the next 5 years or more.

I think the STS community is bigger than this forum would lead you and I to believe. I think a significant number of people are buying these kits from someone not here and having them installed by someone other than a vendor. I think this is natural as this platform progresses and becomes cheaper to acquire.

You said it all right there.

athenG

iTrader: (2)

Did you guys did an Idle relearn at least? My idle is not as bad and pretty much idle around 750rpm and maybe drop/increase 100-200rpm every now and then (Not consistent). My CEL problem seem to disappear after replacing my MAF sensor, replacing my MAF also stabilize my Idle a little. FWIW my car also dont like to idle below 650rpm but is stable above 700rpm.

JonnyC

iTrader: (19)

I don't blame you. That day will come for me sometime, where it just becomes more of a liability. Best of luck with your endeavor - hopefully you are able to get some good money for your parts.

JonnyC

iTrader: (19)

I didn't do a relearn - only reset the ECU. I'll have to look into do that. Otherwise, I can just bump the idle.

DanielW

iTrader: (27)

I had an ecu reflash from when i had bolt ons. Not sure if it affected anything though.

Mike_G

iTrader: (3)

<-- STS owner/lurker... Cars away for the winter

Mike_G

iTrader: (3)

So, Im curious how many of us are kicking around ?
I have had the problem described erratic idle. Added some fuel to the 0% column got some better results. Still not perfect Im sure the temp compensation would help out. Hopefully this spring it will get sorted out.
Happy Holidays
Mike

athenG

iTrader: (2)

First reset your ECU (I did a batter disconnect) then do the entire idle relearn.. adding more fuel will not fix it coz if your 02 sensor, TB or your MAF is malfunctioning then the symptom will go back. Utec Temp Compensation dont take effect until you are on boost so it is non factor in idling. The ECU control everything in close loop.

Try this procedure:



Accelerator Pedal Release Position Learning
1) Leave ACC pedal "as is”
2) Turn IGN switch “ON” – at least 2 sec
3) Turn IGN switch “OFF” – at least 10 sec
4) Turn IGN switch “ON” – at least 2 sec
5) Turn IGN switch “OFF” – at least 10 sec

Wait 10 sec for next procedure

Throttle Valve Closed Position Learning
1) Leave ACC pedal “as is”
2) Turn IGN switch “ON” – appr 3-4 sec
3) Turn IGN switch “OFF” – at least 10 sec


Wait 10 sec for next procedure.. Make sure the car is fully warmed else drive for a few mins before doing the idle air volume learing.

Idle Air Volume Learning
1) Leave ACC pedal “as is”
2) Start engine and warm up to operating temp – temp gauge around middle
3) Turn IGN switch “OFF” – at least 10 sec
4) Turn IGN switch “ON” – 3 sec
5) Fully depress and release ACC pedal – 5 times within 5 sec
6) Wait 7 sec
7) Fully depress ACC pedal for appr 20 sec – during this time CEL blinks
8) When CEL light is “ON”, not blinking – fully release ACC pedal
9) Turn the engine “ON” within 3 sec
10) Start engine and idle
11) Wait 20 sec
12) Rev engine 2-3 times and check IDLE and TIMING


Your idle will be a little off since the ECU is trying to relearn but after a few mins of idling just drive normal.

If that doesn't fix it then try to borrow a MAF sensor and see if it makes a difference. I had some idle problem (P507) and P1273 code and after replacing my MAF pretty much fix ever thing. My idle is also much better after changing the MAF sensor.