94 z28 surging at idle and during 1 & 2 gears
11-11-2011, 01:22 PM
#1
Teching In
Thread Starter
Join Date: Jul 2007
Location: Houston, TX
Posts: 4
Likes: 0
Received 0 Likes
on
0 Posts
94 z28 surging at idle and during 1 & 2 gears Hello everybody, well my car had been parked for about a year, recently I tried to start it up n it takes about 2 to 3 tries then it surges at idle and during 1st & 2nd gear unless I raise the rpms up. I replace the opti, fuel pump, maf, spark plugs, wires. Its also giving me dtc codes 27 and 48. Anyone know what it could be? Its a stock lt1 with cai, mid tubes and borla cat back. Thanks
11-13-2011, 11:55 AM
#2
Teching In
Join Date: Nov 2011
Posts: 4
Likes: 0
Received 0 Likes
on
0 Posts
Code 42 has to do with your ICM; Code 42- Ignition control circuit (ignition module). Check wiring and connections from ignition module and ecm. Replace module only after verifying wiring and connections are not shorted or open.
Your Code 27 reads EGR vacuum control solenoid circuit. Check the EGR solenoid wiring and connections.
Both of the problem would easily explain your problems getting her started and the surge at idle.
Your Code 27 reads EGR vacuum control solenoid circuit. Check the EGR solenoid wiring and connections.
Both of the problem would easily explain your problems getting her started and the surge at idle.
11-27-2011, 09:01 PM
#3
Teching In
Thread Starter
Join Date: Jul 2007
Location: Houston, TX
Posts: 4
Likes: 0
Received 0 Likes
on
0 Posts
If I deleted the egr system do I have to tune the ecm? Could that be the problem? I'm getting a lq4 in my rcsb 08 silverado so I think I might just swap that lt1 for the 5.3
