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Today same thing - really high AFR numbers on WB with the V8r (04-20-19 (1) tune .. Any suggestions on channels to add and to make sure closed loop will potentially work.. All I want to see are the Fuel numbers... It does not seem either way wants to work.. With saving and trying to get into another house... let's just say I need to watch money spent... So, I purchased 02 extenders so I can get the Narrow bands installed into the front 02 positions. At this point, I don't know what will help or what will work.. Here is a question. By going to 3 different tunes - will this confuse the car and make numbers jump around a bit before setting down? Have I confused the car? I sue as heck hope I have not fried my WB 02's.... I just bought those suckers a couple months ago... Hope all is well with everyone... I'm still banding my head trying to get my car on the road...
Here are two versions of the same thing -- open loop and closed loop. I'm assuming at this point the only reliable sensor you have is the bosch in your gauge pod.
SO, this will put some fuel back in to keep it happier, but it's just a stab. If moving the O2's to the fron position and running in closed loop is still not working, i would begin to suspect the ECU has gone bad.
Here is an update of sorts...... I made a huge mistake and did not secure the new power wire I ran from the starter to the positive power block.. Well an Optima Battery with 800 CCA on a hot wire touching a header - not a good thing.... The coating made the hole only look about a quarter inch, well not the case.- more like 1 1/2 inches.. . When this occurred I smelled burning, dash lights went nuts, turned the key off and then began repairs.. Header fixed, all 02 bungs available so NB's installed in front positions and WB's installed in the rear.. Through out today - have not been able to get my car to start... turns over, cranks but not starting.. Took a chance and used my actron scanner and P0335 (Crankshaft position sensor) showed up. Had this go out couple months ago... Symptom appears the same Crank but no start even sounds funny. Going for an AC Delco crank position sensor and see what happens. Will continue to update.. Hope this car is on the road soon... it's been way too long..
Help!!!!!! Replaced CPS and sounds better but still same result. Anyone ever done something like this that can help? Basically, I destroyed my starter to power block wire and blew a nice sized hole in my passenger side header.. As mentioned above the header is fixed. The car cranks but no start. I performed a simple light test on the fuses and everything checked out. I replaced the starter relay, switched the Fuel pump and AC relays around, I connected a hose to the end of my fuel rail and turned the key on - a little bit of fuel came out but no more than that.... So it appears my fuel pump is not working. . I checked all fuses again... Here is where I don't know if i messed up again. I turned the key to on position to check fuses that were not lighting up while off.... I checked several more and then turned the car off... Now my light doesn't work...that's weird.. I then used a multi - meter and checked fuses for continuity and everything checks fine with my meter.
1> Will grounding out the starter wire somehow mess up the fuel pump? That doesn't make sense to me, or is there another problem...I no longer hear the fuel pump turn on when I turn on the key.. So I believe I know the problem just don't' want to waste anymore $$$$.. I can't afford any more mistakes.
2> The car cranks but no start - Would the car still do this if a ground wire got screwed up? I thought if a ground was messed up the car would not do anything.
3> All wires meeting at the power block include trunk mounted Optima battery, the starter wire, and the wire leading to the alternator and then on to the fuse boxes.. I don't have any blown fuses and it would make sense those would go before anything else. For example the fuel pump should be protected by the fuses and relays, the injectors, starter everything..
Awesome guys! Ok, down to the logic..... After swapping relays, still no change, pulled the fuel pump relay inserted paperclip (Pins 87 & 30) and fuel pump flowed like a MF... Good news!!! I tested the Fuel Relay itself with a buddy's relay tester and tested good... Today, and if you can track with me. On the Fuel Pump Relay there are 4 numbers with a diagram... (87, 85 86, 30) Using a circuit tester for power and ground tests went as follow:
Key Off:
87 Red, 85 Green, 86 Green, 30 Green) PIN line up 87 & 85 are vertical with each other, 87 & 86 parallel, 87 & 30 Diagonal
Key On:
87 Red, 85 Red, 86 Green, 30 Green
Key on Fuel Pump fuse pulled.
87 dead, 85 Red, 87 Green, 30 Green
When I turn the key on,, no fuel pump... the thought did cross my mind to leave the paper clip in and see if the car starts.. Knowing it probably will, I'm not going to do that,, risk of burning something else up..
Would be a lot easier with voltages or ohms than light colors:
Red -- Voltage at probe higher than voltage at clip.
Green -- Voltage at clip higher than voltage at probe.
Making sure I got that right
Pin 30 -- incoming power from battery. Fuse pulled, 30 should be dead. Fuse in place, 30 should be 12V even with key off.
Pin 87 -- Load. In this case, fuel pump. Should see ohms (not zero indicating dead short), but no voltage whether key on or off.
---paperclip obviously indicates 30 and 87 are fine---
Pin 86 -- Switched power. should be 12V key on and dead key off.
Pin 85 -- Ground. Should be zero volts to ground and zero ohms to ground.
You say when you pulled the fuse, 87 went dead, not 30. I'm guessing you got these two backwards?
Also, you don't say 86 went dead with key off. It should. Rather, it looks like maybe you have 86 and 85 reversed as well (86 always green?? 85 should be always green i thought)
Where I'm thinking is I do not think 86 should ever go green. pretty sure it is either red or dead. I think your switched power wire may require attention. Otherwise, I would go to the ground wire for the 85 terminal an make sure it is properly grounded.
Would be a lot easier with voltages or ohms than light colors:
Red -- Voltage at probe higher than voltage at clip.
Green -- Voltage at clip higher than voltage at probe.
Making sure I got that right
Pin 30 -- incoming power from battery. Fuse pulled, 30 should be dead. Fuse in place, 30 should be 12V even with key off.
Pin 87 -- Load. In this case, fuel pump. Should see ohms (not zero indicating dead short), but no voltage whether key on or off.
---paperclip obviously indicates 30 and 87 are fine---
Pin 86 -- Switched power. should be 12V key on and dead key off.
Pin 85 -- Ground. Should be zero volts to ground and zero ohms to ground.
You say when you pulled the fuse, 87 went dead, not 30. I'm guessing you got these two backwards?
Also, you don't say 86 went dead with key off. It should. Rather, it looks like maybe you have 86 and 85 reversed as well (86 always green?? 85 should be always green i thought)
Where I'm thinking is I do not think 86 should ever go green. pretty sure it is either red or dead. I think your switched power wire may require attention. Otherwise, I would go to the ground wire for the 85 terminal an make sure it is properly grounded.
Wish I would have taken a picture of the fuse block set up before taking the first one out... Anyone have a picture, just asking?
Standing on the drivers side looking straight down at the fuse / relay block...
Top left corner - PIN 85 Ground circuit KEY ON Meter reading 44.21 volts (Green light but high voltage meter reading...) think you are on to something as with Key OFF there is no voltage on PIN 85.. Now for PIN 85 would that ground circuit have anything to do with the ground connecting to the starter or the ground circuit connecting to the block over by the starter? , or am I looking to the PCM at this point?
Will start looking at my PCM layouts to find PIN 85 connection point.
Pin 85 should be ground. Voltage on pin 85 is no bueno. Also -- 44 volts??????????????
????????????
Battery is only 12. I hope....
Pin 85 should be no different than your negative battery terminal. Its chassis ground. Key on or off does not matter.
Deeper steps taken to research grounding concerns,... Key off and Key on... Engine Ground 12.2 V which according to research states engine grounded properly... Tested suspected Engine to body ground wire from passenger side to block near the starter Tested good 12.2 volts.... This of course with the red meter lead alligator clipped to positive terminal by the fuse block, with touching the ground point and wire.. 12.2 V for completed circuit. The question I have is what is keeping the fuel pump from turning on? Could my attempting to start in this condition have messed up the throttle position sensor?... if I can't start it, hard to get codes. So far the people I know around here and my contacts in H-Town,,, no one seems to know electrical. 1 guy in Austin but getting him over has been difficult. Very open to any wisdom to be shared if possible.
Deeper steps taken to research grounding concerns,... Key off and Key on... Engine Ground 12.2 V which according to research states engine grounded properly... Tested suspected Engine to body ground wire from passenger side to block near the starter Tested good 12.2 volts.... This of course with the red meter lead alligator clipped to positive terminal by the fuse block, with touching the ground point and wire.. 12.2 V for completed circuit. The question I have is what is keeping the fuel pump from turning on? Could my attempting to start in this condition have messed up the throttle position sensor?... if I can't start it, hard to get codes. So far the people I know around here and my contacts in H-Town,,, no one seems to know electrical. 1 guy in Austin but getting him over has been difficult. Very open to any wisdom to be shared if possible.
To my knowledge, TPS does not disable the fuel pump under any circumstances. From your last post, I'm interpreting pin 85 is acting as ground correctly, which is good. And you already know if you jump 30 to 87, it runs, so this rules out a LOT of possibilities.
If you clip to ground, pin 86 should be dead with key off and 12V or red key on. Is this what you're seeing? If not, go into your tune and verify VATS is off. Possibly a consequence of that weird short you had the PCM is now not enabling the fuel pump relay. It's in the System portion of the tune. VATS Enable, drop down menu, select "none". Write the tune. Some have reported you need to write entire to get a VATS disable to stick, but I would still try it write calibration only first.
To my knowledge, TPS does not disable the fuel pump under any circumstances. From your last post, I'm interpreting pin 85 is acting as ground correctly, which is good. And you already know if you jump 30 to 87, it runs, so this rules out a LOT of possibilities.
If you clip to ground, pin 86 should be dead with key off and 12V or red key on. Is this what you're seeing? If not, go into your tune and verify VATS is off. Possibly a consequence of that weird short you had the PCM is now not enabling the fuel pump relay. It's in the System portion of the tune. VATS Enable, drop down menu, select "none". Write the tune. Some have reported you need to write entire to get a VATS disable to stick, but I would still try it write calibration only first.
Yes, to PIN 86 (above) dead when key off and live when key on ( Ironically there is greater than .4 voltage drop which.... Ironically I scanned it and P0335 (Crank Pos Sensor) I just replaced that and the code came back and I only buy GM CPS's now.. I checked the plug and wires, maybe check those again and the pig tail.. I know I did this before... I tried my previous PCM and no start still existed. If PIG Tail and Wires check good to the CPS then would the next step be PCM, again? When I googled my problem I found I am not the only one who has done this, I'm just the one who burned a hole through my header causing additional issues to work out... At least those who read this I hope enjoy learning from my idiotic mistakes.. lol..
Yes, to PIN 86 (above) dead when key off and live when key on ( Ironically there is greater than .4 voltage drop which.... Ironically I scanned it and P0335 (Crank Pos Sensor) I just replaced that and the code came back and I only buy GM CPS's now.. I checked the plug and wires, maybe check those again and the pig tail.. I know I did this before... I tried my previous PCM and no start still existed. If PIG Tail and Wires check good to the CPS then would the next step be PCM, again? When I googled my problem I found I am not the only one who has done this, I'm just the one who burned a hole through my header causing additional issues to work out... At least those who read this I hope enjoy learning from my idiotic mistakes.. lol..
LOL. Well, good news is electrically, everything is testing ok (related to the fuel pump). So, how about VATS? Did you try turning off VATS? I know it was running before via VATS, but since everything checks out electrically, I would at least see if disabling VATS will correct it.
Like I said in previous post - some guys report it will work with a calibration only write. Others say they had to do a write entire. I would try the calibration only write first.
LOL. Well, good news is electrically, everything is testing ok (related to the fuel pump). So, how about VATS? Did you try turning off VATS? I know it was running before via VATS, but since everything checks out electrically, I would at least see if disabling VATS will correct it.
Like I said in previous post - some guys report it will work with a calibration only write. Others say they had to do a write entire. I would try the calibration only write first.
Have not tried turning off VATS yet.... Back when trouble started I remember trying the different tunes and also switching between 3 tunes pretty fast, thinking it may have not been a good idea to do that, but I was stressed at the time.. i tried going back to the tune before the high AFR numbers. still sounds the same as far as the Crank and NO Start.. Tuesday of next week I plan to go to LKQ and/or Austin Wrench a Part and hopefully find another PCM. Last one came out of a Tahoe.. .There is a wrecked 4th Gen FIrehawk around my area someone wants to sell... still trying to find the person.. In your opinion, what tune should I try and start with? Are the two latest tunes Ok based on the incorrect AFR number reporting? Get my car inspected & legal and now it doesn't run - Dab-nab-it! Lol
Ok, latest news: Found a PCM out of a suburban...have not purchased the licenses yet as I wanted to double check the current PCM before wasting another $100.... Please verify the truth - : A contact through my work stated if I can WRITE ENTIRE on the current PCM (Which I did with a previous tune I know works) and it accepted it.- then the PCM is supposedly good... Attempted to start the car and same result.. Crank No Start.. Pulled a code and got the CPS P0335 again... The CPS has been replaced (only GM). I have audible tested CPS wires to know they are good. Tested/checked all grounds. Even the block ground tested fine. So, I have put lke 4 Crank Position Sensors in this car since starting to have problems. If all wiring is checking out, then what is causing the Crank Position Sensor Code to ignite immediately. To me it has to be the PCM.... I know the Crank Position Senor is responsible for most of the car to function properly. Any ideas, Suggestions, anything anyone has an idea on..... .
Hello sir. Sorry to hear of problems. What comes to mind first is the code you keep receiving for the CPS. As you have replaced the sensor several times so that takes that out. What my mind says is even though the wires test fine there is still something wrong. To take out any question with the wiring would be to run new wires the whole way, from pcm to sensor, & maybe new connector on CPS. As the idea of maybe the PCM I cant combat. Make sure to check, maybe remove, the terminals, on PCM connector, to CPS circuit. The code still popping up means there is still a problem with the CPS system.
Also reading that the fuel pump will come on when jumped with paper clip, but not with relay, sounds odd. At least it comes on with paper clip so you know all is working. Try different relay?
Just some ideas. Hope you get it all worked out man.
Does anyone know for sure if you can complete a "write entire" new tune to a PCM having a single circuit issue? Still driving me crazy and now I have a deadlines (1 great hope and 1 absolute). Everyone has been super cool about all of this and I do appreciate it...
04-28-2019, 04:18 PM
