TECH 1 GURUS....HELP!
Thread Starter
Burning Brakes
Joined: May 2001
Posts: 790
Likes: 2
TECH 1 GURUS....HELP!
No idle at start up...slowly improves on warmup to about 650.
Here are some numbers from my tech1
engine off: throttle 0%-.60volts 100%-4.06 volts (max)
L/R 02 both 453
0 RPM-4 degrees advance (when it was running this went to about 24)
L/R pulse width 23.2 mSEC
IAC 145 Learned 32
I'm not sure what any of this means (except timing advance)...but it appears my TPS is working ok....how about the rest?...or is there some numbers I can get for you to help me diagnose this problem.
Car used to idle up on start up til it warmed up...then settle down to a good idle. I've cleaned the TB and IAC. Think my IAC is shot? Also, I get a bit of pop on returning back to idle after reving a bit. :confused: :banghead:
Here are some numbers from my tech1
engine off: throttle 0%-.60volts 100%-4.06 volts (max)
L/R 02 both 453
0 RPM-4 degrees advance (when it was running this went to about 24)
L/R pulse width 23.2 mSEC
IAC 145 Learned 32
I'm not sure what any of this means (except timing advance)...but it appears my TPS is working ok....how about the rest?...or is there some numbers I can get for you to help me diagnose this problem.
Car used to idle up on start up til it warmed up...then settle down to a good idle. I've cleaned the TB and IAC. Think my IAC is shot? Also, I get a bit of pop on returning back to idle after reving a bit. :confused: :banghead:
Safety Car
Joined: Feb 1999
Posts: 3,504
Likes: 4
From: Mexico Beach FL
Re: TECH 1 GURUS....HELP! (emoshn)
The Tech-1 is bi-directional -- that means, along with reading parameters, it can send commands to various components.
The Tech-1 can send a command to the IAC to tell it to increase or decrease the idle speed. If you tell the Tech-1 to increase idle speed and it does, then you know the Tech-1 is controlling the idle speed by moving the IAC. This tells you the IAC is working. If the idle doesn't change when you command it through the Tech-1, you need to find out why.
Tom Piper
The Tech-1 can send a command to the IAC to tell it to increase or decrease the idle speed. If you tell the Tech-1 to increase idle speed and it does, then you know the Tech-1 is controlling the idle speed by moving the IAC. This tells you the IAC is working. If the idle doesn't change when you command it through the Tech-1, you need to find out why.
Tom Piper
Thread Starter
Burning Brakes
Joined: May 2001
Posts: 790
Likes: 2
Re: TECH 1 GURUS....HELP! (Tom Piper)
The Tech1 will not increase the idle. I've tried that. I know I can set the idle up or down when in the IAC adjust mode...but very little happens. It appears to want to but as soon as I exit that test, it goes back to the idle it was at. Does that mean my IAC is bad?
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: TECH 1 GURUS....HELP! (emoshn)
I'm not sure why your IAC is at 145counts but it should be around 20counts.
You might pull the IAC and clean it & the bore and clean the TB.
Also check for a vacuum leak.
You might pull the IAC and clean it & the bore and clean the TB.
Also check for a vacuum leak.
Thread Starter
Burning Brakes
Joined: May 2001
Posts: 790
Likes: 2
Re: TECH 1 GURUS....HELP! (65Z01)
The IAC count is with the engine off. How does one adjust the IAC count...it was doing this before I cleaned it and TB, checked connections, checked for vaccuum leaks. Does it have anything to do with Block Learn. Seems like I read somewhere that I have to activate Block Learn and drive the car to get it to reset?
I have no codes in either the ECM or CCM.
I just went out to the garage and started it again. Ran Fine. Just like it supposed to!!!!
Must be an intermittent problem. Guess I'll buy a new IAC and connector and replace it or have it on hand if it starts acting up again. Oxygen sensor too. Does the 92 have one or two oxygen sensors?
When it comes to the TECH1...guess I'm gonna have to learn by guess and by damn. :)
I have no codes in either the ECM or CCM.
I just went out to the garage and started it again. Ran Fine. Just like it supposed to!!!!
Must be an intermittent problem. Guess I'll buy a new IAC and connector and replace it or have it on hand if it starts acting up again. Oxygen sensor too. Does the 92 have one or two oxygen sensors?
When it comes to the TECH1...guess I'm gonna have to learn by guess and by damn. :)
Safety Car
Joined: Feb 2002
Posts: 4,212
Likes: 10
From: Sun City West Az
Re: TECH 1 GURUS....HELP! (emoshn)
Never having the $ to afford a TECH-1, I can't says as how to check the O2's with it. If you can access their input to the ECM, the mv should be "swinging" across 450mv. .....spending as much time below as above that number. Also, if the O2's are spending to much time on one side of the 450mv, the BLM's will be above or below 128 depending on the A/F ratio that the O2's are seeing. Hope that makes sense.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
2027 Corvette vs The World: Every Model vs Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
5 MOST and 5 LEAST Popular Corvette Model Years in History!
Joe Kucinski
2027 Corvette Buyer's Guide: Everything You Need to Know!
Joe Kucinski
10 Things C8 Corvette Owners Hate (But Won't Tell You)
Joe Kucinski
10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!
Brett Foote
Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)
Joe Kucinski
Grand Sport & Grand Sport X Launch Alongside All-New 535hp LS6 V8!
Michael S. Palmer
5 Reasons Bad Drivers Crash & 5 Ways to Avoid a Costly Mistake!
Joe Kucinski
Safety Car
Joined: Feb 2002
Posts: 4,212
Likes: 10
From: Sun City West Az
Re: TECH 1 GURUS....HELP! (emoshn)
It shows the 128 figure...without running. so that would be the history. BLM is BLOCK LEARN MODULE?
So to answer your question, if the car is off you are looking at the long term stored memory;BLM in THAT cell.