car died, bad idle, backfiring?

[Roc87]

Hey Guys, hope you can help me out on this. Haven't driven the GN since Tuesday, had the K&N off to do a cleaning. Got it put back on today (cleaned it tuesday night, let it dry until Thursday and oiled it thurs. also). It idled bad all day, then on the way home, it died (In a really bad spot ) Before it died, I had gone thru the drive thru at sonic and while idling, it died twice but started fine both times. Anyways when in died going up a steep hill on a two lane road it wouldn't start. Got somebody to pull me up the hill onto the side of the road and around 20 minutes later it started. Idled even more rough, but it got me home. The SES light was on the whole way. Checked on DS and it was code 41, the Cam sensor. So I replaced top of cam sensor and it was the same. SO, in the past hour I've swapped out most of the parts off the Iroc to try on the Buick. Things I've tried:
Top of cam sensor
O2 sensor
MAF sensor
Ign. module/Coil pack
ECM

Car still idles bad, and dies at idle. BLM's at idle is down to 90. IAC counts seem good, and both MAF's showing 6 at idle. Of course this has to happen the night before most of us here in Albuquerque/Rio Rancho are going to go to the Strip Help!

 

[badboy86gn2]

Dam i was hoping some of the stuff we talked about would work perhaps tomarrow we will get to the bottom of it

p.s
early so we can pull the slicks off mine and have some fun

Johnny

perhaps the whole cam sensor has to come out and reset???

 

[Razor]

BLM90 means rich as hell, ecm pulling fuel out.

Whats the base fuel pressure set at? On what chip?

Sounds like bad MAF.. but I see you replaced it.. Post back if you find the problem.

 

[Roc87]

Fuel pressure is 40 (No vac.) and the chip is one of my own.
Thanks for the thoughts, I tried the MAF because on one of them, it seemed to idle better when it was unplugged, but ran the same with the other MAF

 

[.38 special]

I would hook up a volt meter to the cam sensor and make sure it is set right.
Or possibly, (Im probably wrong) you could have jumped a tooth on the timing chain and that is throwing off the cam sensor.

 

[badboy86gn2]

get some rest buddy

 

[Roc87]

How do I use the volt meter to test? It might very well be a jumped tooth on the timing chain, since I believe it's stock

 

[snodgrass]

i would check the crank sensor with a scanner, or replace it.

 

[Razor]

Ok..my understanding of these sensors is, the cam sensor is used to to synchronize injector1 firing. If the cam sensor were to be off, and the injector fired lets say against a closed valve, then typically you could see the motor backfire or run wrong for the first few seconds. Once the motor has fired, it runs off the crank sensor. So with a running motor you can unplug the cam sensor and it will stay running..

What throws me off is your BLM at 90, which means its really rich and pulling fuel out. What determines its rich is the O2, fuel pressure, and the MAF as the primary three.

Put a fuel pressure guage on the rail and see if you dont have injectors bleeding of pressure adding additional fuel. So if you shut your motor off..the fuel pressure should remain constant until fired again.

Unplugging your MAF should let the engine run, not very well..but if you damaged the chain, this should let you diagnose that.

Try to determine if its mechanical or electronic..

Dunno what else to say.