01ws666

So i'm having a local guy do a street tune with EFI live for the mod's in sig but he says he cant finish tuning with it stuck in open loop. The first thing we thought was the o2 sensors were bad because they wer'nt showing much oscelation durring data loging, they were only moving between .430 and .471mv also had SES codes p0134 and p0154 wich I believe is sensor 1 left and right bank, insufficent activity... the car still threw these codes after swapping out the old 02's for the new one's So I changed both 02's for new bosch one's and it still wont switch over to closed loop! So next we thought it might be the MAF since he saw I had a slp one so we swapped it for a good stocker and nothing! the only other thing I can think of would be the coolant temp sensor on the drivers side head that I somewhat broke the connector on but its held on good with a dab of super glue... Is there anything else I can check? maybe my pcm is shot?

sreve

iTrader: (3)

it will not go closed loop with those codes.
tuning is only a good option for a car that just needs a tune. not one that has
other problems.
a temp sensor that is open will make the pcm belive its -40* outside and will never
go closed loop. it will not show a code for the temp sensor the pcm will belive it.

01ws666

ok I realize the car is still throwing the codes for the 02's and it wont go into closed loop with them but I put new 02's on and still got the 134 and 154 codes so could the problem be my pcm or the wiring harness? as for the coolant temp sens. it is in there good i just broke the clip on the connector so it wouldnt stay plugged in the sens. I know thats in good cuz the car ran like **** without it... also I think I read that that sensor is the one that controlls the guages and that there is another one that the pcm reads in the water pump somewhere but I didnt see it... also the guage on EFI live was reading 180-185* would it have been reading this correctly if the sensor was broke or would it have just read -40*? Sorry if these are dumb questions I am not a tuner, just trying to fix my car so my tuner can finish the job I already payed him for. lol

Doc

iTrader: (9)

Get a new temp sensor and a new tuner. That should have been an easy one.

01ws666

Ya thanks for the advice! the problems not my tuner its my car...and I dont see you even trying to be helpfull and answer my questions...where the tuner I'm using went out of his way spending over an hour researching the wiring diagrams for a f-body 02 sensors and actually come up with some helpfull advice! you should try it if you want to convince people they should go to you for tuning

sreve

iTrader: (3)

with 185* on the scanner your ok there. could be dead sensors or wiring.
check the fuses for the O2s. heres some copy\paste on the codes.




For the specific DTCs required for each system, see table. Systems such as fuel delivery, misfire, and
comprehensive components may not be listed in a system status list. These tests run continuously on some
vehicles and may not require an indicator. The PCM compares the actual MAF sensor frequency signal to the
predicted MAF value. This comparison will determine if the signal is stuck based on a lack of variation, or is
too low or too high for a given operating condition. DTC P0101 sets if the actual MAF sensor frequency signal
is not within a predetermined range of the calculated MAF value. The Powertrain Control Module (PCM)
supplies 5 volts to the MAP sensor on the 5 -volt reference circuit. The PCM also provides a ground on the low
reference circuit. The MAP sensor provides a signal to the PCM on the MAP sensor signal circuit which is
relative to the pressure changes in the manifold. The PCM should detect a low signal voltage at a low MAP,
such as during an idle or a deceleration. The PCM should detect a high signal voltage at a high MAP, such as
the ignition is ON, with the engine OFF, or at a Wide Open Throttle (WOT). The MAP sensor is also used in
order to determine the Barometric (BARO) pressure. This occurs when the ignition switch is turned ON, with
the engine OFF. The BARO reading may also be updated whenever the engine is operated at WOT. The PCM
monitors the MAP sensor signal for voltage outside of the normal range. The PCM calculates a predicted value
for the MAP sensor based on throttle position and engine speed. The PCM then compares the predicted value to
the actual MAP sensor signal. The DTC P0106 will set if the MAP sensor signal is not within the predicted
range.
Diagnostic Procedures
1. Did you perform the Diagnostic System Check-Engine Controls? If yes, go to next step. If no, see
DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS under SELF -DIAGNOSTIC SYSTEM.
2. Install a scan tool. Idle the engine at the normal operating temperature. Operate the engine above 1200
RPM for 2 minutes. Use a scan tool in order to observe the HO2S voltage. Does the scan tool indicate the
HO2S voltage varies outside 350 - 550 mV? If yes, go to next step. If no, go to step 4 .
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start
the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze
Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next
step. If no, see INTERMITTENT CONDITIONS under SELF -DIAGNOSTIC SYSTEM.
4. Turn ON the ignition, with the engine OFF. Disconnect the affected HO2S. Jumper the HO2S high signal
circuit to a known -good ground. Jumper the HO2S low signal circuit to a known-good ground. Use a scan
tool in order to observe the HO2S voltage. Is the HO2S voltage below 200 mV? If yes, go to step 8 . If
no, go to next step.
5. Remove both jumper wires. Measure the voltage from the HO2S low signal circuit to a battery ground
using the Digital Multimeter (DMM). Does the DMM indicate that the voltage is near 5 V? If yes, go to
next step. If no, go to step 7 .
6. Turn OFF the ignition. Disconnect the PCM connector. Test the continuity of the HO2S high signal
circuit. Repair the open circuit if no continuity is indicated on the DMM. Did you find and correct the
condition? If yes, go to step 12 . If no, go to step 10 .
7. Turn OFF the ignition. Disconnect the PCM connector. Test the continuity of the HO2S low signal
circuit. If the DMM indicates no continuity, repair the open connection or the poor connection. Did you
find and correct the condition? If yes, go to step 12 . If no, go to step 10 .
NOTE: Important Before you proceed with this DTC, inspect the HO2S for being
secure. A loose sensor can cause this DTC to set.

8. Inspect the HO2S circuits for a poor connection at the HO2S harness connector. If you find a poor
connection, repair the connection as necessary. Did you find and repair the condition? If yes, go to step
12 . If no, go to next step.
9. Replace the affected HO2S. See appropriate REMOVAL, OVERHAUL & INSTALLATION article.
After repairs, go to step 12 .
10. Inspect the HO2S circuits for a poor connection at the PCM. If you find a poor connection, repair the
connection as necessary. Did you find and correct the condition? If yes, go to step 12 . If no, go to next
step.
11. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram
PCM. See POWERTRAIN CONTROL MODULE under PROGRAMMING. After repairs, go to next
step.
12. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the
vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If
no, go to step 2 .
13. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that
you have not diagnosed? If yes, see DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no, system
is okay.
Thoroughly inspect any circuitry that is suspected of causing the intermittent complaint. See under SELF -
DIAGNOSTIC SYSTEM. The Powertrain Control Module (PCM) monitors the voltage on the 5 -volt reference
1 circuit. If the voltage is out of tolerance, the PCM will set DTC P1635.
2002 Chevrolet Camaro SS
2002 ENGINE PERFORMANCE Self- Diagnostics - 5.7L Camaro & Firebird
.
© 2005 Mitchell Repair Information Company

edcmat-l1

iTrader: (10)

While I disagree with Doc that its your coolant temp sensor, I do agree with him, you should probably seek another tuner. Simply because it should be pretty easily diagnosed.
If the sensors are sticking in the 440 mv range, there may be a problem with the connections. Even if its staying in open loop, chances of it staying right at 440 mv is slim to none. If they are providing feedback, they should be over 700 mv after a minute or so, after they heat up.
The first thing you need to do, is unplug the sensors, and with the scanner hooked up, see if you can force them high, and then low. An easy way to do this, is connect a jumper wire to the signal wire going back to the PCM, take the end of that jumper wire, which you should strip bare for an inch or so, touch it to ground, and have someone look at the scanner. The 02 voltage should read zero. Next, hold the bare part of the wire in one and, and touch you other hand to 12 volts. Like the starter stud. The 02 voltage on the scanner should read over 1 volt.
If that all works as it should, you probably have an issue with the female pins in the harness connector right where the 02s plug in.

01ws666

Ok thank you very much for being helpfull Sreve and Edcmat-l1!! After I check the fuses for the 02 heaters (wich was one of the suggestions by my tuner) If thats not the problem, I'll follow the diagnostic copy/ paste you posted and see what I come up with...thank's again

Slvr00Bird

iTrader: (2)

Is it just me or is this guy asking for help and then being a complete *** hat????

Lt1Porsche

iTrader: (6)

I think its just you.......he's asking for help on a particular issue and is being told his tuner is ****. How about people just help the man out with what he asked and dont comment that the tuner is stupid. If I was the tuner I wouldnt look far into fixing the car. Just tuning. If the car has an issue that needs to be fixed it is returned to the customer to be fixed then returned. Ive had numerous shops do this to me on multiple vehicles. Mainly drag bikes.

01ws666

slvr00bird I dont see you offering any advice in fact your sole purpose of posting in here is to talk **** (something i would never do unless I actually had some helpfull advice to go with my criticism!) so unless your a tuner and have something helpfull to add I'd say of my thread!


Thank you to Lt1Porsche for standing up for me. Lol. you know where I'm coming from I'm paying this guy less than 200 bucks for a complete street tune... Not to fix my car for me! I already feel he's gone out of his way more than he had too to help me fix the problem... He let me use his jack and tools to change my 02's in his driveway, he researched 02 wiring diagrams and has reaserched other tuning threads, posted his own threads, totaling more than two hours online on top of spending two hours in his drive way helping me change my 02's, swap MAF's, checking my grounds, checking my pcm even crawling under my car himself to check them out! I'd say he's been more than helpfull... And just because he has not before encountered this problem does not make him a bad tuner! he's doing his best to research the problem and help me out..

edcmat-l1

iTrader: (10)

440 is not just the switch point. IT IS THE DEFAULT VALUE THAT SHOWS UP ON THE SCANNER IF THEY ARE UNPLUGGED. Actually its 443mv usually.
Now, we have run into each other in other threads, and have butted heads. You need to realize I have 15 years exp as a diagnostic tech before ever tuning my first car.
That being said, back to the 02s not heating up. They dont necessarily need the heaters to work to heat up. If you go out and drive the car hard, the exhaust temps should heat them adequately to make them work. How did 02s work before heaters? Actually, the heaters are only there to get the computer into closed loop faster. So, like I said, if they are working, providing feedback, they should be in the 700 mv range, shortly after heating up, even without the heaters working, even if the computer has a problem and wont go into closed loop. The test I told him to do will quickly diagnose the wiring in the car, and the computers ability to "see" the change in voltage. You're basically forcing them low, and then high, and seeing if they show up on your scanner as such.
Finally, I believe it should be a prerequisite for a tuner to be a good diagnostic tech. You gotta understand how the system works, before you can go changin stuff.

Doc

iTrader: (9)

Sorry to hurt your feelings. I was trying to point out that putting "broke" or glued parts back on your performance car is not the troubleshooting approach I would take. Good luck on your project.

sreve

iTrader: (3)

if your going to dig into it you will need this see the pdf

01ws666

Hey thanks for all your help to the guy's that offered advice! Got the issue fixed and it was much simpler than I thought... It was in Edcmat-l1's post where he stated that 440 is not just the switch point. IT IS THE DEFAULT VALUE THAT SHOWS UP ON THE SCANNER IF THEY ARE UNPLUGGED. That got me thinking I had just picked up my car from the local transmission shop the day before I took it to my tuner and I remember seeing it up on the lift at the shop with my trans. out and remembered they Unplugged my 02's for access to my transmission...I'm sure by now you can see where I'm going with this...Ya because I dont have rear 02's the plugs are just hanging there and because the rear plugs are right over the tranny and much easier to see than the fronts the shop plugged my front 02's in the connectors for the rear 02's!!! Lol stupid shop! Oh well now I have brand new 02's instead of the splice's that came with the pacesetter LT's

edcmat-l1

iTrader: (10)

I'll just post this in case tblu92 wants to come back here and tell me again I dont know what I'm talking about. He has a habit of that. And he has a habit of being wrong too. I know you dont know anything about that, 01ws666.
Glad ya got it fixed.
And I stand by my belief that you should be a good diagnostic guy before you can be a tuner.

Eurospec2

iTrader: (2)

I agree

XxMerlinxX

iTrader: (2)

I'm just quoting this for future searches. I've been looking for that schematic for a while now and just randomly stumbled across it while looking for something else. Thanks for posting that up sreve.

Keywords- O2 sensor. Voltage. Diagram. Wires. Harness.