LT1 Swap Computer Issue - Team Camaro Tech
Troubleshooting Diagnosing problems done here.

LinkBack Thread Tools Display Modes
post #1 of 5 (permalink) Old Sep 30th, 06, 08:00 AM Thread Starter
Join Date: May 2005
Posts: 26
LT1 Swap Computer Issue

Have a 67 RS/SS Convertible with a 94 LT1 donor engine/computer. Following are the known mods/specs (I'm sure some are irrelevant for this question but just in case). The computer is not communication with any programming tool. On the OBDII Harness (Painless Harness) there are the 12volt and two 5volt reference lines present.

Symptoms: Idle all over the board - mostly 2500 rpm but drops down to 800rpm occasionally, headers are running extremely hot (rockers have just been adjusted), occasionally severe hesitation.

I am trying to figure out what the correct steps to troubleshoot this system would be. Also, assuming the computer is bad, what system (cost effective as I have blown my wad on the rest of the car!) would you recommend?

Donor Car: 94 Camaro SS VIN# Unknown, Codes on the computer: 86BMJRK1414575ZL, BMJR, 16210011
Vortech Blower
Cam: Lt4 Hotcam GM Part #24502586
Heads: LT1 Ported to 2.05 intake & 1.67 exhaust
Comp Springs w/ Titanium Caps
Pistons: TRW Dished Blower Pistons 9:1 compression
Stock rods & crank
Engine bored .030 over
2 Bolt main
Fuel system: Rock Valley fuel pump pressure 45 psi
Injectors: SVO 36lb injectors
Clutch: 11" centerforce
Rear Axle: Strange Ford 9" rear posi 4:11 gears
Roller rocker tips 1.6
Vortech Supercharger
Wilwood Braking system 12.1" plated/drilled/slotted rotors front and back w/ 4 piston calipers and Wilwood main cylinder
Power Steering
Power Windows
Airride Technologies Rear Suspension
Oversized Aluminum Radiator
Flex-a-Lite Dual Cooling fans
RockValley Stainless Steel Gas Tank
Autometer Phantom Gauges
Martz Drag Front End 3" drop spindle coil overs
Box Reinforced Frame
Detroit Speed Subframe Connectors
Painless wiring harness (engine and car)
Magnaflow 3" dual exhaust
Ceramic Coated Headers

Last edited by StompS; Sep 30th, 06 at 11:18 AM.
StompS is offline  
Sponsored Links
post #2 of 5 (permalink) Old Oct 12th, 06, 12:22 PM
Gold Lifetime Member
Join Date: Feb 2006
Location: Fairhope Alabama
Posts: 436
Re: LT1 Swap Computer Issue

Stomps, I am not a computer gearhead but have some lt1 experience from my 95 ss impala. Here are some things to look at-

You have an OBD 1 car (pre 1996) and an OBD 2 harness-cold be the whole problem.

Also all of the mods you have on that engine will definately require a reprogram of the computer. Bryan Herter of PCMS for less does a lot of work for guys on the impala ss forum and can help you out at a reasonable price. Also tons of info on the forum about modded lt1s.

Good Luck
Camuchi is offline  
post #3 of 5 (permalink) Old Oct 12th, 06, 02:55 PM Thread Starter
Join Date: May 2005
Posts: 26
Re: LT1 Swap Computer Issue

Funny you should recommend Bryan, as I called him an he did, in fact, program my computer. Everything is OK now except that I am running about 1100RPM at idle and hesitating and some backfiring when decelerating and then giving a little gas. Laso, I am burning about twice as much fuel as I should be and my Air/Fuel guage is still all over the board. I just cleaned my sensor in my blower tube but it did not make a change. I have been looking for a vacuum leak but am coming up short...

Portland, Oregon
67 RS/SS Vert w/Supercharged 94 LT1
StompS is offline  
post #4 of 5 (permalink) Old Oct 13th, 06, 05:51 PM
Senior Tech
Join Date: Jul 2005
Location: Tucson, Az
Posts: 283
Re: LT1 Swap Computer Issue

You may want to try "". They have some great info and links for TPI troubleshooting.


Last edited by Hot 67; Oct 13th, 06 at 06:08 PM. Reason: Incorrect Info
Hot 67 is offline  
post #5 of 5 (permalink) Old Oct 13th, 06, 06:07 PM
Senior Tech
Join Date: Jul 2005
Location: Tucson, Az
Posts: 283
Re: LT1 Swap Computer Issue

You may want to check ouy "" , they have lots of good info and links for troubleshooting TPI.


Last edited by Hot 67; Oct 13th, 06 at 06:09 PM. Reason: Delete Double Entry
Hot 67 is offline  
Sponsored Links

Quick Reply

Register Now

In order to be able to post messages on the Team Camaro Tech forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address.
NOTE we receive a lot of registrations with bad email addresses. IF you do not receive your confirmation email you will not be able to post. contact support and we will try and help.
Be sure you enter a valid email address and check your spam folder as well.

Email Address:


Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Similar Threads
Thread Thread Starter Forum Replies Last Post
Help with leaf spring swap gusher Brakes, Suspension & Steering 8 Dec 28th, 06 09:39 AM
lt1 swap TheGr8Schlotzky Performance 1 Jun 10th, 06 08:37 AM
LT1 motor swap Seneca SS Engine 0 Mar 30th, 06 05:09 PM
Drive line vibrations - big block swap 69OrangeTwist Engine 1 Mar 28th, 06 04:16 PM
LT1 Computer programming Tokala Bench Racing 3 Apr 13th, 05 04:34 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome