Derrick86

I have kinda been stumped here. I have an 86 camaro 305 tpi. I have recently replaced the intake gasket and water pump. I retimed it and set the base ignition timing at 6-8 btdc. The car runs just running off the base timing with the ignition bypass wire disconnected. But the idle is unstable. It will bounce around 700- 1100 rpm its not steady. If i shut the car off plug the bypass wire back in, the car will run for about 10 seconds unless i give it gas. If i don't it dies after a few seconds.

ploegi

vacuum leak.

Derrick86

Would fuel trims show that? Block learn?

Pro

yea
U need a way to view the data, and also to record via your phone and upload whats going on. youtube is free, upload a video there.
also something like these are cheap these days. i use one. The guy is great, and the app he wrote is super easy and he keeps it updated constantly
https://www.ebay.com/itm/12-Pin-ALDL...r/272388698454

luvofjah

iTrader: (2)

As ploegi stated, my car had the same issue, and it had vacuum leaks...
O2 was up / down, etc... Fixed leaks, fixed idle... Be sure to check all bolts on tpi / base / runners etc are tight...

Derrick86

This is some data I got off the car. I broke them down into 2 columns one is with the bypass ignition wire unplugged and the other is plugged in. I took pictures of the scanner, the o2 reading is low in all the pictures but it was bouncing around like it should. Also I had to have the rpm higher with it plugged in due to it not running at idle.

BYPASS WIRE UNPLUGGED BYPASS WIRE PLUGGED IN

RPM- 700- 925 RPM-1450-1550
02-31 02-90
CLOSED LOOP CLOSED LOOP
TPS- .56 TPS-.76
IAC POSITION-55 IAC POSITION- 24
INTEGRATOR- 128-131 INTEGRATOR- 132
EXHAUST OXYGEN- LEAN EXHAUST OXYGEN- LEAN
BLOCK LEARN- 128 BLOCK LEARN- 126
FT CELL-0 FT CELL- 2
02 READY- YES 02 READY- YES
02 CROSSCOUNTS- 180 O2 CROSSCOUNTS- 208
BASE PW- 2.2 BASE PW- 1.7
DECEL ENLEARN- NO DECEL ENLEARN- NO
DESIRED IDLE- 750 DESIRED IDLE-750
A/F LEARNED- YES A/F LEARNED- YES
COOLANT-176F’ COOLANT-183’F
MAT-99’F MAT-95’F
MAF (GM/SEC)- 6 MAF- 13
AIRFLOW (GM/SEC)- 6 AIRFLOW- 13
LOAD/LV8-44 LOAD/LV8- 41
SPARK ADVANCE- 0’ SPARK ADVANCE-28’
KNOCK-59 KNOCK- 17
KNOCK RETARD- 0’ KNOCK RETARD- 0’
PROM ID-14391 PRIME ID- 14391
BATTERY-13.5V BATTERY- 13.5V
FUEL PUMP-14.2V FUEL PUMP- 14.2V
HIGH BATTERY- NO EGR DUTY%- 0
MAF BURNOFF- OFF EGR DIAG SW - ON
EGR DUTY%- 0 CCP DUTY CYCLE- 0
EGR DIAG SW - ON DECEL ENLEARN- NO
CCP DUTY CYCLE- 0 AIR DIVERT SOL- DIV
DECEL ENLEARN- NO AIR SWITCH SOL- CONV
AIR DIVERT SOL- DIV
AIR SWITCH SOL- CONV

Derrick86

Anyone?

BadSS

I always "rinse and repeat" the minimal idle speed adjustment, TPS adjustment, and the timing adjustments when someone has a hunting idle. I've had to go through the process a few times to get everything "matched up" on some cars.

Read through the information in the first link below and you'll see what issues you can have when the settings are off. The second link is the procedures to set everything. If you end up moving the idle set screw up or down to adjust the minimal idle speed, you'll need to reset the base timing and TPS (rinse and repeat). Best I remember I would usually see around 15-20 IAC count with a stock 305. Yours is showing 55 which would leave me to believe you need to screw in the throttle adjustment to give you a little higher idle with the IAC disconnected.

http://www.gmtuners.com/tech/TPS_IAC.htm

http://www.fuelinjection.com/tpi/for...0Procedure.pdf

Pro

Derrick, what scan tool are you using? A snapshot like that doesnt help much. A spreadsheet of data, real-time helps out much more.

Derrick86

I'm using a 2500 Snap on scanner, its an old one but gets the job done I need it to lol. Is there a way to set idle, timing, tps, and IAC in park? I have the trans out right now for a rebuild and I am waiting on a torque converter. So I cant' set any of that stuff in drive is there a way to do so in Park? I would like to have the engine stuff done before the trans goes in so everything is good to go.