What are the most common symptoms besides IAC motor and TPS voltage? Any particular vacuum area's to check? I've looked all over the vehicle and can't find a single vacuum line messed up, IAC and TPS are working correctly. Im about to scan it tonight but wondering if there is anything I missed? Its idling at about 2000 rpm.

 

Ok, just scanned it using datamaster and the result is:

Idling at 1600 rpm.

IAC at idle is at 0 steps (WTF? Usually at 22 or some other number, it rises when I give it gas)

Codes were:

MAT low
MAP Low
O2 sensors failed, left and right (These are brand new)
The readings on the o2's stayed at 453 and 448. bouncing between both numbers, I know this is not normal.

Spark advance was at 30 * at idle.

Anyone got a clue to this? If you need more details let me know, i'll run the datamaster log through.

Im thinking the morons at the body shop snagged one of my wires, the IAT was at -40* and its 93* out right now.

 

I had a problem with my engine idle a few years ago. I changed out the throttle position sensor on the throttle body and it fixed it right up.

I don't know if it is the same problem I had, but I hope it helps.

Joe

 

TPS was fine, .57 volts at idle.

 

Wow no one?

 

, usually someone posts with, my car isn't working and gets tons of replies, I be specific and bleh. .

 

The inlet air temp sensor is easy to check with an ohm meter. Shoebox has the values of resistance vs. temperature on his Tech Pages, and they are also in my online ScanMaster writeup. -40degF corresponds to infinite resistance.... the wire is off the sensor, or the sensor is dead (open circuit).

What were your MAP readings? Since MAP is sort of the "opposite" of vacuum, reading "low" contradicts the possibility of a vacuum leak.

The readings for your O2 sensors would indicate they are not working at all. The voltage you are seeing is the voltage the PCM applies to the sensors. Possibly they are not heating up - but there would be a code for the faulty heater circuits.

 

Map was at 28.4 I believe, I think normal idle for me it would stay at 22.8, at work currently and can't see the scan. Im not sure what "MAT Low" is. What confuses me is my IAC is at 0 steps at idle, but works fine when giving it gas and the motor seems to be stepping fine, but stays at 0 during idle. Is the spark advance at 30* normal? It also rises when giving it gas.

 

Also, the O2's are 1 month old, im not sure why they took a crap. Infact the left was replaced twice because it took a crap within one week. Any way to clean them? Im positive their getting heated up.

 

The ignition advance comes off a table of advance vs. RPM. The advance is higher than normal because your RPM is higher than normal.

"MAT" = IAT.... inlet air temp sensor.

The IAC has dropped to "0" because it is trying to reduce idle RPM, and it has "bottomed out" at fully closed and can't bring the idle down any further. Also, remember.... the IAC "counts" are simply what the PCM is trying to set it at. There is no feedback to insure it is actually moving to the position the PCM commands. Maybe its stuck open? Did you check the IAC using the procedure on Shoebox's Tech Pages?

Is the cable loose enough to let the blades close all the way? Have you taken a look to make sure they are closed? Did you move the idle stop screw? Could you have bent the throttle blades (you'd be surprised what a nitrous backfire can do to them )? Is the bottom plate tight? Is the TB to manifold gasket good?

Its the "MAP low" that makes me wonder. If you are getting values like 28kPa and 22kPa, it is unusually low (what altitude are you at?). That's just the opposite of what you would see with an air leak or the throttle blades open too far.

 

Im near the rio, not sure what elevation im at but it ain't high. Throttle blades open and close just fine. Idle screw was never touched, no slack on the throttle cable and closes correctly with foot off the gas. What is a normal MAP rating?

 

MAP it idle is typically 1/3 of barometric pressure (BAR). With a 103kPa BAR, a stock cam should be in the range of 33-36kPa. If you switch units, 9.5-10.0"Hg.

 

Well, suppose i'll wait ti'll I get home to check it out. Any clue on what is causing my O2's to take a crap? Anyway to clean them?

 

You would have to seriously contaminate them - silcon from non-sensor-safe RTV, coolant, leaded fuel, touching them with oily hands, using anti-sieze on the thread (they are pre-coated with the correct, CONDUCTIVE anti-sieze), contaminating the outside of the shell with something. But as they get contaminated, they generally "slow down" first, don't just "die". Do you have any kind of extensions? Did you check the fuses for the heater circuits?

With all those codes kicking off, I would also consider the possibility of a faulty PCM or engine ground(s).

 

Im leaning towards engine grounds, I had the car being painted for a month and a bunch of dumbass body workers all over it. Im going to recheck them all. Neither O2 was exposed to any of the above mentioned.