LT1-LT4 Modifications 1993-97 Gen II Small Block V8

Lt1 bad idle hypertech not communicating

Thread Tools
 
Search this Thread
 
Old Jul 8, 2016 | 10:54 AM
  #1  
shezam's Avatar
Thread Starter
Teching In
 
Joined: Jun 2016
Posts: 17
Likes: 1
Default Lt1 bad idle hypertech not communicating

Alright you guys have helped me in the past. And hypertech are no help at all 1994 trans am cold idle super low when check engine light comes on (closed loop) idle goes up a little to high and irregular i tryed pulling out hypertech to check codes and chip says cannot communicate with computer call hypertech hypertec says chip does not interfear with checking codes. Well ive owned the car since 97 3rd engine 5th trans 3rd rearend and i remember when i first took the car for recall and they needed me to remove the chip guy said you can't check codes with chip installed.i have tryed and its a jumper wire and no codes just turns air pump on anyone have this proplem or point me in the right direction it has a lunati cam but it is slightly bigger than stock and lunati said it wont affect computer and it didnt the car is basically stock runs great wot just lousy idle i did plug egr valve any ideas thanks
Reply
Old Jul 8, 2016 | 11:08 AM
  #2  
hokeplaya05's Avatar
TECH Fanatic
10 Year Member
Photogenic
Photoriffic
Liked
iTrader: (3)
 
Joined: Mar 2013
Posts: 1,208
Likes: 77
From: new hampshire
Default

get a real tune on it, hypertech is junk. talk to Solomon (lt1pcmtuning.com) and he can set you up. changing the cam and deleting the EGR will definitely affect the computer, CEL is probably because of the EGR delete.

also, use some punctuation in your posts. very tough to read/understand your run on sentences.
Reply
Old Jul 8, 2016 | 10:57 PM
  #3  
CamaroVsMustang's Avatar
Teching In
 
Joined: Nov 2014
Posts: 45
Likes: 0
Default

Hypertech is OK... but there are only limited values u can change with any hand help programmer... I'd look into updating ur computer to a 96-97 ECM, and change the harness so u can go OBD2... and pull codes if u need them.

The other thing I would suggest is idle air control valve may not be functioning.... so it's causing crappy low idle... 93-95 ECM is dead... upgrade... and things become a hell of lot nicer...
Reply
Old Jul 11, 2016 | 11:21 AM
  #4  
hokeplaya05's Avatar
TECH Fanatic
10 Year Member
Photogenic
Photoriffic
Liked
iTrader: (3)
 
Joined: Mar 2013
Posts: 1,208
Likes: 77
From: new hampshire
Default

Originally Posted by CamaroVsMustang
Hypertech is OK... but there are only limited values u can change with any hand help programmer... I'd look into updating ur computer to a 96-97 ECM, and change the harness so u can go OBD2... and pull codes if u need them.

... 93-95 ECM is dead... upgrade... and things become a hell of lot nicer...
completely unnecessary to do, would be a waste of time and money to swap over to obdII for what the OP needs. just send it out for a mail order tune (soloman, PCMforless, etc.), or if you have someone locally that can dyno tune it do that.
Reply
Old Jul 12, 2016 | 10:10 AM
  #5  
moehorsepower's Avatar
TECH Addict
iTrader: (3)
 
Joined: Feb 2003
Posts: 2,334
Likes: 17
From: Texas
Default

Originally Posted by hokeplaya05
completely unnecessary to do, would be a waste of time and money to swap over to obdII for what the OP needs. just send it out for a mail order tune (soloman, PCMforless, etc.), or if you have someone locally that can dyno tune it do that.

^^ Exactly, why in the heck would you want to go thru all that trouble of changing a wire harness just for a low idle, makes no sense...
Reply
Old Feb 20, 2017 | 12:03 AM
  #6  
Impala project's Avatar
Registered User
 
Joined: Feb 2017
Posts: 1
Likes: 0
From: Texas
Default

I need help with a high idle problem on my 94 Impala..... I don't know how to use this forum to post something......
It's got a high idle when the car is warmed up or just starting, I've read a lot of forums and tried some things that have been suggested. It slams into gear and shifts hard from 1-2nd. I did a test that I saw was suggested on another forum where you have the car running and then you un plug the IAC and after that you turn the car off plug it back in and start it and it will bring the idle down and it did but it creeps back up if I leave it plugged in.

I have replaced the IAC the TPS the coolant temp sensor I have checked for vacuum leaks with carb cleaner or TB cleaner and fixed the leaks that were needed, I've checked for exhaust leaks with a sniffer, I've checked the throttle blades and they are working properly not catching and the screw is not touching to keep them open, I've cleaned the TB and MAF, I've checked power to the plugs for the TPS and IAC, I've ran the car at night to look for arcing and there's none..... I'm sure there's a couple things I'm forgetting but I'm at a loss, I haven't had the car scanned yet but I need the get this fixed before I do anything else.... I am doing cam and heads after I get this all figured out and having Solomon tune the car for that..... Also the egr isn't sticking or stuck. The car seems to stumble a little but there is no loss of power at WOT or anywhere between
Reply




All times are GMT -5. The time now is 07:06 AM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE