GmTruckHQ is the resource on GM Trucks, Suspension, engine information, Body Modifications, painting tutorials.  Modifications to suit every need, budget and whim
Home   Forum   Chat   Register   Today's Posts   Search  

GMTruckHQ is the premier GM Truck Site on the internet. Registered Users do not see the above ads. Please Register - It's Free!

Go Back   GmTruckHQ > Tech Discussions > Diagnostic Trouble Codes (DTCs)

no DTCs, engine dies in seconds


Reply
 
Thread Tools Display Modes
Old 08-07-2012, 01:46 PM   #1
LS-10's Avatar
Send PM    Add to friends    Homepage
Join Date: Aug 2012
 
  LS-10 is offline    
LS-10
Junior Member

Have installed a 98 LS1 into an 89 S10. Time to start it up... 2 symptoms.
1. Turn key to "on". bright "MIL" light. engine starts up & runs smooth for 5-10 seconds, then dies. No trouble codes.

2. Turn key to "on". dim "MIL" light, engine starts & immediately dies. No trouble codes.

We are using OBDcom interface with a laptop. No trouble codes, but it "connects" and can read O2 sensor voltages.

Our only 2 ideas are:
1. VATS not "turned off" in the PCM.

2. Oil pressure sensor reading low pressure? (We hooked up the original S10 oil pressure gauge to the LS1 oil pressure sending unit. Could it be loading the sending unit output enough to cause it to read low in the PCM?)

We tried to be very careful & thorough when integrating the 2 systems together and modified the Corvette engine harness and the original S10 harness to integrate them.

Any ideas?

Thanks!

Reply With Quote
Old 08-23-2012, 01:00 PM   #2
LS-10's Avatar
Send PM    Add to friends    Homepage
Join Date: Aug 2012
 
  LS-10 is offline    
LS-10
Junior Member

Problem solved!
Turned out to be a flag in the PCM. Peculiar to 97 & 98 Vettes (I think), there is a flag in the PCM for steering column lock. When programming with EFI Live, it asks the question "steering column lock installed?" We had the answer set to "NO", thinking that that meant "OFF". Well, it had to be set to "YES". Now it starts up & runs fine!

Movin on......

Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not 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

Forum Jump


 


Vin Decoder Info