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BluRT00
06-20-2009, 09:31 PM
Ok I have been reading on acouple R/T forums that guys are having weird idle issues. Well mine has been acting up within the last 2 weeks. I have replaced the spark plugs/ cape and rotor with the autolite plugs and msd brass contactor cap and rotor. I also went ahead and replaced my idle air circuit sensor on the back of the throttle body. The old one wasn't brass and had bad rust on the plunger head. So got the direct replacment delphi one for it. Fired the truck up and she runs good for the first 5 or so mins idling a tick above 750 rpm. Then she starts to creep down, and I had my scanner on watching the PCM is calling for target of 608 rpm. So it settles down to that and falls under it to as low as 580 rpm. This all started acouple weeks ago when I could that some of my rubber plugs blew off the nipples on the side of the M1. Once I fixed the plugs bang she started idling low. No codes are thrown at all, my vac/boost gauge stays at 20 hg vac like it has since day one installed. All I have on my mind next to check is pull air hat and see if the blades are sticking. Then once that was thinking my 1 yr old bosch 2 O2 sensors are fubared up from me running race leaded gas in it last yr/beginning of this year. Ok sorry for novel just throwing this out there to get any other ideas for you guys. The truck once you hit the gas comes to life and runs like a bat out of hell. She just wants to idle to low and throw my AFR in the 13.9 range where she used to idle higher and be around 14.9 to 15.2.

ODDFIRE V10
07-23-2009, 02:45 PM
Ok I have been reading on acouple R/T forums that guys are having weird idle issues. Well mine has been acting up within the last 2 weeks. I have replaced the spark plugs/ cape and rotor with the autolite plugs and msd brass contactor cap and rotor. I also went ahead and replaced my idle air circuit sensor on the back of the throttle body. The old one wasn't brass and had bad rust on the plunger head. So got the direct replacment delphi one for it. Fired the truck up and she runs good for the first 5 or so mins idling a tick above 750 rpm. Then she starts to creep down, and I had my scanner on watching the PCM is calling for target of 608 rpm. So it settles down to that and falls under it to as low as 580 rpm. This all started acouple weeks ago when I could that some of my rubber plugs blew off the nipples on the side of the M1. Once I fixed the plugs bang she started idling low. No codes are thrown at all, my vac/boost gauge stays at 20 hg vac like it has since day one installed. All I have on my mind next to check is pull air hat and see if the blades are sticking. Then once that was thinking my 1 yr old bosch 2 O2 sensors are fubared up from me running race leaded gas in it last yr/beginning of this year. Ok sorry for novel just throwing this out there to get any other ideas for you guys. The truck once you hit the gas comes to life and runs like a bat out of hell. She just wants to idle to low and throw my AFR in the 13.9 range where she used to idle higher and be around 14.9 to 15.2.

POISONED O2's

98Dak408
08-06-2009, 11:03 PM
Ok I have been reading on acouple R/T forums that guys are having weird idle issues. Well mine has been acting up within the last 2 weeks. I have replaced the spark plugs/ cape and rotor with the autolite plugs and msd brass contactor cap and rotor. I also went ahead and replaced my idle air circuit sensor on the back of the throttle body. The old one wasn't brass and had bad rust on the plunger head. So got the direct replacment delphi one for it. Fired the truck up and she runs good for the first 5 or so mins idling a tick above 750 rpm. Then she starts to creep down, and I had my scanner on watching the PCM is calling for target of 608 rpm. So it settles down to that and falls under it to as low as 580 rpm. This all started acouple weeks ago when I could that some of my rubber plugs blew off the nipples on the side of the M1. Once I fixed the plugs bang she started idling low. No codes are thrown at all, my vac/boost gauge stays at 20 hg vac like it has since day one installed. All I have on my mind next to check is pull air hat and see if the blades are sticking. Then once that was thinking my 1 yr old bosch 2 O2 sensors are fubared up from me running race leaded gas in it last yr/beginning of this year. Ok sorry for novel just throwing this out there to get any other ideas for you guys. The truck once you hit the gas comes to life and runs like a bat out of hell. She just wants to idle to low and throw my AFR in the 13.9 range where she used to idle higher and be around 14.9 to 15.2.How's it running now?

BluRT00
08-07-2009, 03:33 AM
I changed the O2's and even have a used 58 MM TB on it with different sensors. Doesn't dump fuel anymore at idle just runs 15.2 afr and sits at around 650 rpm. Now I am picking up a can of lube to lube the shafts of the TB cause its sticking. Other then that truck seems to run like a bat out of hell. I am basically at a loss, no vac/exhaust leaks at all. So guess I will live with it.

98Dak408
08-07-2009, 03:45 AM
What about resetting you IAC counts?

BluRT00
08-07-2009, 05:55 PM
What about resetting you IAC counts?

I could give that a shot, but doesn't the PCM relearn it anyway and put it where its happy?

Nolan
08-07-2009, 09:39 PM
I could give that a shot, but doesn't the PCM relearn it anyway and put it where its happy?

Yes, but the IAC only has a certain range of movement so if it has to move all the way to one end of its range just to maintain the correct idle speed it may not have enough range to compensate for all conditions.

Setting the throttle blade (idle) postion so the correct idle speed is in the middle of the IAC's range of movement lets it better compensate for the conditions.

The factory sets the throttle blade position then presses in a plug to prevent tampering.

Nolan

blackknight
08-07-2009, 10:30 PM
are you supercharged or you just running a vacuum/boost gauge for the heck of it? where you pulling your vacuum from?

BluRT00
08-08-2009, 02:16 AM
I am tied into the intake pulling the Vac reading, and yes I am supercharged.