cknoma2005

iTrader: (3)

I recently replaced the knock sensors, harness and opsu when tracking down an oil leak. After putting it back together the SEL flashed at first startup and now has flashed one other time since the first one. If I turn the car off and back on again everything is fine. Was wondering what this could be. I had oreilly auto parts scan for codes but they didn't see anything. The car runs great other than that.

Any ideas?

my_99Z

iTrader: (4)

While its flashing does the car run any different? Any loss of power? Normally a flashing SEL light means multiple random misfire, I'm surprised the computer wouldn't show any codes for that. Perhaps the knock sensors aren't working right, I had a friend who was having problems with misfires and it turned out to be the knock sensors he installed one of them was bad. I'm not really sure what it could be other than that if you aren't even getting codes

cknoma2005

iTrader: (3)

It does not appear to be running any different. The car is cammed so its hard for me to tell if its missing. I suspect its the knock sensor or harness I installed since it never did that before I switched them out. If the knock sensor was bad wouldn't it log a code? Maybe the scanners that Oreilly uses can't see it? It has only happened twice in over a week of driving it everyday.

Suggestions?

MontecarloDrag

iTrader: (3)

It's normal for a cammed engine, the PCM thinks the low vacuum and power at idle is because of misfire. Not all cams cause it but most big cams do.

You need to modify the misfire tables and give the engine the air, fuel and spark it wants at idle to keep the PCM happy without disabling misfire detection

cknoma2005

iTrader: (3)

Thank you for your insight. So, you are saying I need to go back to my tuner?

I just think its funny that it started after replacing the knock sensors and harness and that it only has happened at cold start up. Why wouldn't it log a code? The plug wires are new(plus i havn't touched them since i installed them), plugs are AC Delco Iridiums (that have maybe 45k on them) Is it worth checking the intake bolts? I know I torqued them down according to specs as well as the knock sensors.

MontecarloDrag

iTrader: (3)

If it doesn't give a DTC, it may be other issue, but it's hard to know without the car or a datalog

cknoma2005

iTrader: (3)

What would you suggest me to do?

MontecarloDrag

iTrader: (3)

Well, I have only seen a blinking DTC when severe misfire was happening, the engines were running very poorly. If yours is working good and doesn't pop a code, it may not be misfire.

I'd put new plugs just to be sure. Check plug wires, vacuum hoses and vacuum leaks. Check if grounds and battery terminals are not corroded or loose.
Get a scanner to check for codes and basic troubleshooting

Old Geezer

iTrader: (3)

Knock sensor torqued to?

cknoma2005

iTrader: (3)

15 ft\lb
the same that I torqued the opsu to when I replaced it.