fast idle, cannot communicate to obdII

mmtphoto

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All of a sudden tonight, my 96 mark viii started idleing fast-2200 rpm in neutral, 1300+ in drive-it happened when I got of the expressway. I pretty much have to stand on teh brakes at lights, and if I have to wait for one of those 'eternity' lights, I put it in neutral so I dont make it worse on the trans than necessary-got it home, took the air tube off expecting to find something interfering with the throttle-nothing. Everything seems to be connected too. It ran ok on the way home, not hot, but the 'check engine light' came on.
I have a scanner (Actron 9145) but there is no OBD II conector by the driver location? the hood sticker says it is OBDII-My questions are-where is the IAC on this thing? what does it look like, it sure seems like a likely culprit to me-and what is the deal with the lack of OBDII connector on an OBDII car??? HELP-anyone have any clue? thanks
 
check on the passenger side of the center console unde rthe dash.

thats where it is on Tbirds. never messed with a 2G mark.
 
I had the same problem and it was the idle air control valve.I actually used one off of a mustang 5.0 that i had layin around.It worked. BTW--good luck gettin it off
 
Where Is It???

I had the same problem and it was the idle air control valve.I actually used one off of a mustang 5.0 that i had layin around.It worked. BTW--good luck gettin it off

WHERE IS IT??? the IAC, I mean-what does it look like? anyone have a photo? Does anyone have 96, and where is the OBD II connector? thanks
 
found both, man, my vision and patience are not what they used to be-the IAC location qualifies the 4.6 designers a medal for the stupidist place to locate a sensor that will fail-I disconnected it for now, it still idles and I can drive it the way it is. anyone around Glenside Pa want to replace it. I've got money...
 
change an egr valve on a 95 4.6 tbird. thats a fun job.

i have yet to look for it on the mark....not looking foward to its location.
 
Not a fun place. Last week I attempted it, took the windshield scroud off, air tube, TB, and used a small ratchet and socket on the right bolt and was able to break it loose but the dam left one, the screw stud, I used a small ignition wrench to try and break it loose. Couldn't get much of a grip but I tried so hard with just my fingers and wound up with a fracture of the middle finger. Needless to say I wasn't able to loosen it so it stays the way it is until I heal. Happy Easter to all on the board.:)
 
Not a fun place. Last week I attempted it, took the windshield scroud off, air tube, TB, and used a small ratchet and socket on the right bolt and was able to break it loose but the dam left one, the screw stud, I used a small ignition wrench to try and break it loose. Couldn't get much of a grip but I tried so hard with just my fingers and wound up with a fracture of the middle finger. Needless to say I wasn't able to loosen it so it stays the way it is until I heal. Happy Easter to all on the board.:)

Funny it would be your MIDDLE FINGER, that seems poetic-
I disconnected the battery terminals, clamped them together for a half hour, cleaned the posts, and hooked up the IAC again, put it all back together and it WORKS again-idles at 750, no CEL, it's all good-
my wife remembered that this happened before in my '93 years ago, she said I did something that worked the next day- I went online and read a Toyota blog about people having the same problems with Camrys (98-99) and this is one of the fixes-bingo!.
Try it, it worked for me, if you get a P1506 (IAC overspeed) or a P1507 (underspeed), that means it (the IAC)works, and the ECM is just not able to calibrate it-if you disconnect it, it has to start over again. After driving it, the idle is like before, I also noted that the trans seems to shift 'better'-when I got this one ('96, in September '06), one of the very first things I did was the 1-2 accumulator with a complete drain of the trans and torque converter, new filter to hopefully cure poor shift-it holds first forever if you get on it from a stop, and you have to get off the throttle to get it to shift-that seems to be better now, but it still takes too long to shift between gears, unlike my '93, which would bark the tires on 1-2 shifts.
Since these cars have so many electrical connections and modules, it makes sense that clearing out the ECM's settings and allowing it to start over again can solve some problems. It worked for me, thank God, 'cause I'd break more than a middle finger replacing that bi&ch!
 
MMT Photo, Thanks for the tip, I will have to try it, can't see it hurting anything and if it works, darn side better than trying to change it. When I tried changing it, I popped the black dust cover that's above the screw bolt for more room and still couldn't budge the dam thing and a fractured finger to boot.:( Thanks again for the tip:)
 
My trans is out right now and I am replacing the EGR and IAC at the same time pretty easy to do with the trans out of the way.
 
so its in about the same place as the tbird then?

i did the egr on a tbird with the trans out and it was easy.
 
yeah i am guessing its in the same spot (driversides head connected to the rear of the intake) I had to replace that tube last summer and it was a huge PITA.
 

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