LQ4 into a 3rd Gen/1972 Nova
03-13-2012, 12:10 PM
#781
I only plan on trying to drag race it once.. when it's tuned and driving nicely, just to see what it can do. If they let me run down the strip, cool, if not then I guess I'll have to stick to abusing the crap out of it on the road course and having a bit on the street.
I rigged the fuel pump right up to the battery so I could start it sooner, so it is not being powered by the PCM-controlled fuel pump relay that came wired into my Speartech harness. I know the PCM was still on when the key was hot and in cranking, because the HPTuners scanner was showing rpm's when cranking as well as ambient temp and throttle position, however I don't recall if the injector bank gauges were flashing. I have a feeling the injectors weren't getting a pulse. I'll try cranking it tonight while scanning and first seeing if the fuel pump relay is outputting power. If it isn't then clearly the PCM doesn't want to give the engine gas, but if it is outputting power and the injector banks just aren't pulsing, I'll have to do some digging thru my tune. Arg.
VATS was disabled on the new speed density tune I wrote to the PCM, however I should read that tune back onto the laptop to make sure everything copied over right. Mark had a good idea that maybe in the process of the Write-Entire from the previous MAF setup to the new 3bar Speed Density tune, the VATS might've been re-enabled somehow, if that's even possible. Altho I would think that if VATS was re-enabled then the engine would at least try to stumble/catch/fire at least for a couple seconds.
I rigged the fuel pump right up to the battery so I could start it sooner, so it is not being powered by the PCM-controlled fuel pump relay that came wired into my Speartech harness. I know the PCM was still on when the key was hot and in cranking, because the HPTuners scanner was showing rpm's when cranking as well as ambient temp and throttle position, however I don't recall if the injector bank gauges were flashing. I have a feeling the injectors weren't getting a pulse. I'll try cranking it tonight while scanning and first seeing if the fuel pump relay is outputting power. If it isn't then clearly the PCM doesn't want to give the engine gas, but if it is outputting power and the injector banks just aren't pulsing, I'll have to do some digging thru my tune. Arg.
VATS was disabled on the new speed density tune I wrote to the PCM, however I should read that tune back onto the laptop to make sure everything copied over right. Mark had a good idea that maybe in the process of the Write-Entire from the previous MAF setup to the new 3bar Speed Density tune, the VATS might've been re-enabled somehow, if that's even possible. Altho I would think that if VATS was re-enabled then the engine would at least try to stumble/catch/fire at least for a couple seconds.
03-14-2012, 08:02 AM
#782
I had a very simialr problem when I treid to fire my '71 conversion for the first time. Come to find out, where a had tapped off of the fuse block for my hot lead, was only hot when the key was in the run position, not in the start position, changed it, and it popped right off. Good Luck.
03-19-2012, 08:19 PM
#784
I was out all weekend with food poisoning from friday night, which was really shitty because i wanted to dedicate all weekend to getting this ****** running. Like Mark said, gotta start at the basics. Will check spark, injector voltage, fuel pump relay output voltage during cranking (of computer controlled relay, right now the fuel pump is just rigged to the battery). The one thing that is suspect in my eyes is that when I re-flashed the ECM back to a MAF configuration and loaded the previous tune on it, it still cranked and all that but was still not giving the injectors a pulse.
Only things I have changed hardware-wise since the engine last ran are:
1) MAF wiring snipped all except IAT sensor, which I re-wired to a Typhoon sensor, which was reading 7 degrees celcius when I was cranking it, which makes sense because it felt that temp in the garage and the coolant temp was reading 6 degrees
2) injector plugs re-wired to USCAR plug from the stock truck plugs (EV1??)
3) different pedal. I wanted to redo my initial DBW frankenpedal but a guy wanted it and also had a stock truck pedal so we traded. I'm not getting any pedal DTC and the pedal reads 19% just sitting there and 100% when floored.. could it read properly but still let the TAC module give the computer a code. I remember reading Crosstraining's thread about his pedal making his ECM not want to fire.
I have ECM ground to the dash, harness ground to the head, and block ground to the subframe.
I am getting a P0622 DTC (only code being thrown) for bad alternator f-circuit, not sure what that could be but I'm thinking because I painted the alternator body (masked the coils) silver, could the alternator body not be completing ground to the head/block and this screwing with whatever this f-circuit reading is?
Also, this was a Speartech harness that ran great the last time I fired the engine. It has 4 fuses all tapped into one IGN wire, and the fuses were all good last time I checked but I will recheck.
Cars suck.
Only things I have changed hardware-wise since the engine last ran are:
1) MAF wiring snipped all except IAT sensor, which I re-wired to a Typhoon sensor, which was reading 7 degrees celcius when I was cranking it, which makes sense because it felt that temp in the garage and the coolant temp was reading 6 degrees
2) injector plugs re-wired to USCAR plug from the stock truck plugs (EV1??)
3) different pedal. I wanted to redo my initial DBW frankenpedal but a guy wanted it and also had a stock truck pedal so we traded. I'm not getting any pedal DTC and the pedal reads 19% just sitting there and 100% when floored.. could it read properly but still let the TAC module give the computer a code. I remember reading Crosstraining's thread about his pedal making his ECM not want to fire.
I have ECM ground to the dash, harness ground to the head, and block ground to the subframe.
I am getting a P0622 DTC (only code being thrown) for bad alternator f-circuit, not sure what that could be but I'm thinking because I painted the alternator body (masked the coils) silver, could the alternator body not be completing ground to the head/block and this screwing with whatever this f-circuit reading is?
Also, this was a Speartech harness that ran great the last time I fired the engine. It has 4 fuses all tapped into one IGN wire, and the fuses were all good last time I checked but I will recheck.
Cars suck.
03-19-2012, 09:08 PM
#785
have you pinged one of the injection sponsors? or speartech? they should be able to tell you if the injectors are polarity-specific or not.
And re: alternator F circuit. From a GM service manual:
After reading this article, I'm fairly confident that the F circuit code you're seeing is a result of the engine not firing, not vice versa.
And re: alternator F circuit. From a GM service manual:
The PCM monitors the duty cycle of the generator through the F circuit. As the generator load increases, the PCM will adjust the idle speed accordingly. If the IPC does not see any activity from the PCM on the F circuit, the IPC will illuminate the volts telltale lamp.
03-20-2012, 02:36 AM
#786
One thing I just ran into that may or may not help. Are you getting a tach signal while spinning the engine over? If not you crank positioning sensor is bad. The reluctor and CKP not only control the firing order, it pulses the injectors, sends out a tach signal, etc. etc. Just a thought! Steve Hilter from SSP wiring diagnosed my problem from halfway across the nation. Look for the tach signal, if you have one your CKP is good, if no signal is there you may have found the culprit.
03-20-2012, 06:06 AM
#787
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I hope your feeling better soon. Sounds like you have a handle on things! I hope she starts and purrrs nicely for you!
03-20-2012, 09:51 AM
#788
One thing I just ran into that may or may not help. Are you getting a tach signal while spinning the engine over? If not you crank positioning sensor is bad. The reluctor and CKP not only control the firing order, it pulses the injectors, sends out a tach signal, etc. etc. Just a thought! Steve Hilter from SSP wiring diagnosed my problem from halfway across the nation. Look for the tach signal, if you have one your CKP is good, if no signal is there you may have found the culprit.
03-21-2012, 12:54 AM
#790
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I brought my Camaro over on Sunday hoping that it running outside the garage might rub off on the old Nova... Guess not... I guess I'll have to come back this weekend, (if it's dry), and actually get dirty...
03-21-2012, 03:19 PM
#791
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I was out all weekend with food poisoning from friday night, which was really shitty because i wanted to dedicate all weekend to getting this ****** running. Like Mark said, gotta start at the basics. Will check spark, injector voltage, fuel pump relay output voltage during cranking (of computer controlled relay, right now the fuel pump is just rigged to the battery). The one thing that is suspect in my eyes is that when I re-flashed the ECM back to a MAF configuration and loaded the previous tune on it, it still cranked and all that but was still not giving the injectors a pulse.
Only things I have changed hardware-wise since the engine last ran are:
1) MAF wiring snipped all except IAT sensor, which I re-wired to a Typhoon sensor, which was reading 7 degrees celcius when I was cranking it, which makes sense because it felt that temp in the garage and the coolant temp was reading 6 degrees
2) injector plugs re-wired to USCAR plug from the stock truck plugs (EV1??)
3) different pedal. I wanted to redo my initial DBW frankenpedal but a guy wanted it and also had a stock truck pedal so we traded. I'm not getting any pedal DTC and the pedal reads 19% just sitting there and 100% when floored.. could it read properly but still let the TAC module give the computer a code. I remember reading Crosstraining's thread about his pedal making his ECM not want to fire.
I have ECM ground to the dash, harness ground to the head, and block ground to the subframe.
Also, this was a Speartech harness that ran great the last time I fired the engine. It has 4 fuses all tapped into one IGN wire, and the fuses were all good last time I checked but I will recheck.
Cars suck.
Only things I have changed hardware-wise since the engine last ran are:
1) MAF wiring snipped all except IAT sensor, which I re-wired to a Typhoon sensor, which was reading 7 degrees celcius when I was cranking it, which makes sense because it felt that temp in the garage and the coolant temp was reading 6 degrees
2) injector plugs re-wired to USCAR plug from the stock truck plugs (EV1??)
3) different pedal. I wanted to redo my initial DBW frankenpedal but a guy wanted it and also had a stock truck pedal so we traded. I'm not getting any pedal DTC and the pedal reads 19% just sitting there and 100% when floored.. could it read properly but still let the TAC module give the computer a code. I remember reading Crosstraining's thread about his pedal making his ECM not want to fire.
I have ECM ground to the dash, harness ground to the head, and block ground to the subframe.
Also, this was a Speartech harness that ran great the last time I fired the engine. It has 4 fuses all tapped into one IGN wire, and the fuses were all good last time I checked but I will recheck.
Cars suck.
Sounds like #3 will need to be fixed whether its your no-start problem or not. All the headaches I see people having with DBW pedals made me not want to try one.
As strange as it may sound, are there any plugs on your harness that are the same and could be swapped? I always thought that these GM harness had a unique plug for each sensor, but I had an 03' chevy 4.3 modified for standalone that had the TPS and an emission plug that got mixed up once and caused a no-start. Would probably throw a code in your case though.
What is the advantage of the typhoon IAT sensor?
Get it finished up! I need to hear some turbo whistle and 6.0 growl for inspiration
03-22-2012, 12:11 AM
#792
No real advantage to the Typhoon IAT I don't think , other than it uses the right plug and the actual sensor is very low-profile so it shouldn't interupt airflow much.
Checked the injector plugs, I get 12V when switched on, so the injectors are getting power. Other wire didn't have ground, but would make sense since the injector pulse I'm lacking is a switched ground?
Checked the plugs, they aren't sparking when the body is grounded.
Heads are grounded to block, block is grounded to frame. Harness ground terminal has continuity to subframe ground location. PCM ground has continuity to subframe ground location.
Upon cranking still zero injector pulse according to HPTuners.
There is also zero output voltage from the fuel pump relay 12+ output wire that came pre-wired into the Speartech harness.
Just had a thought. I can't remember if I tapped the "IGN On" hookup wire on the Speartech harness to the Run wire or Accessory wire on the body harness. Maybe switching to the 2nd gen Camaro steering column I have now (was stock Nova one before) had a slight change in the wiring/connectivity of the ignition switch box in the column and allow an interruption when changing key positions? Would an Accessory output have power cut off to it during cranking? Might make sense since in every car I've owned the aftermarket deck would restart when going from Cranking -> Run. Funny though that on the HPtuners scanner it didn't seemed to indicate any interruption in power/sensor signals when going from ACC -> Run -> Crank -> Run -> ACC
Checked the injector plugs, I get 12V when switched on, so the injectors are getting power. Other wire didn't have ground, but would make sense since the injector pulse I'm lacking is a switched ground?
Checked the plugs, they aren't sparking when the body is grounded.
Heads are grounded to block, block is grounded to frame. Harness ground terminal has continuity to subframe ground location. PCM ground has continuity to subframe ground location.
Upon cranking still zero injector pulse according to HPTuners.
There is also zero output voltage from the fuel pump relay 12+ output wire that came pre-wired into the Speartech harness.
Just had a thought. I can't remember if I tapped the "IGN On" hookup wire on the Speartech harness to the Run wire or Accessory wire on the body harness. Maybe switching to the 2nd gen Camaro steering column I have now (was stock Nova one before) had a slight change in the wiring/connectivity of the ignition switch box in the column and allow an interruption when changing key positions? Would an Accessory output have power cut off to it during cranking? Might make sense since in every car I've owned the aftermarket deck would restart when going from Cranking -> Run. Funny though that on the HPtuners scanner it didn't seemed to indicate any interruption in power/sensor signals when going from ACC -> Run -> Crank -> Run -> ACC
03-22-2012, 08:18 AM
#794
Need to have someone hit the key to "crank" while you check power to everything with a meter.
I had a similar issue.
I had one simple sire not plugged in....took my a good day to finally see it dangling under the dash.
Check the most obvious first before you go to extremes....good luck!
I had a similar issue.
I had one simple sire not plugged in....took my a good day to finally see it dangling under the dash.
Check the most obvious first before you go to extremes....good luck!
03-23-2012, 12:34 AM
#795
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The IAT sensor swap is usually done when eliminating a 5 wire MAF/IAT combo. In the crank position some accesories are dropped. That is usually why on original harnesses at the starter there is a second small wire, usually orange and possibly a fuseable link, that goes back to the ignition coil, or system at least. It is an aditional contact that is hot only while cranking to feed the ignition circuit. I don't suspect that is your problem though, as you would lose connection in HPtuners upon cranking. Should be sunny Saturday, I guess I'll come over. If you want.
03-26-2012, 02:05 PM
#796
Mark came over on Saturday. I thought it was gonna be something like poke at a couple sensors and look at a plug and then we just scratch our heads at the computer screen, but we actually got a good amount of stuff done. We got it to fire a good couple dozen times but it would never catch and stay on, would just putter out after 1 second. And no.. VATS is not on.
1st problem was the switchable power connection to the computer.. it was connected to a lead on the ignition switch that's only powered during Run. I had to do a bunch of poking around after Mark left and found out that the switch on the 2nd gen column I have doesn't have an ACC power out.. no combo's of switch leads at least. Then we found the lead that gets power during Run & Crank.. but there was a brief power interuption that the PCM didn't seem to like. Found a power combination of a switch lead that is hot only in Run and then another that is hot in Run & Crank, and now the computer gets uninterrupted power during cranking. And so injectors get pulse during cranking!
Also found that the MAP sensor I was thinking was 2bar was actually 2.5bar... shouldn't change too much but is another source of error. Going to pick up the proper 2bar sensor after work today.
Apparently my injector offset table is zero'd out, which I'll have to compare with some other tunes tonight and fix that. Will try and start it up again tonight, hopefully all goes well.
Obligatory picture. Texted this to a friend and got back the response "Holy wet pants"... I'd have to agree. Mark I want your effing car.
1st problem was the switchable power connection to the computer.. it was connected to a lead on the ignition switch that's only powered during Run. I had to do a bunch of poking around after Mark left and found out that the switch on the 2nd gen column I have doesn't have an ACC power out.. no combo's of switch leads at least. Then we found the lead that gets power during Run & Crank.. but there was a brief power interuption that the PCM didn't seem to like. Found a power combination of a switch lead that is hot only in Run and then another that is hot in Run & Crank, and now the computer gets uninterrupted power during cranking. And so injectors get pulse during cranking!
Also found that the MAP sensor I was thinking was 2bar was actually 2.5bar... shouldn't change too much but is another source of error. Going to pick up the proper 2bar sensor after work today.
Apparently my injector offset table is zero'd out, which I'll have to compare with some other tunes tonight and fix that. Will try and start it up again tonight, hopefully all goes well.
Obligatory picture. Texted this to a friend and got back the response "Holy wet pants"... I'd have to agree. Mark I want your effing car.
03-26-2012, 06:34 PM
#797
FroJoe,
Glad to see you are getting real close. Yeah. Mark's camaro looks sweet. But then again. I'm partial to 2nd gen/RSs.
Glad to see you are getting real close. Yeah. Mark's camaro looks sweet. But then again. I'm partial to 2nd gen/RSs.
03-26-2012, 10:01 PM
#798
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Here's a pic of the column wiring. Upper right corner. The combinations are described and what results you get. We'll crack this thing soon!
http://www.nastyz28.com/camaro/wire/73w-ip.jpg
http://www.nastyz28.com/camaro/wire/73w-ip.jpg
03-28-2012, 10:51 PM
#799
Well it runs... kindof.
As per internet reading I think I didn't do the proper Write sequence on the PCM, so I started from scratch and did:
1) Write Entire of speed density tune
2) Turn off ignition, turn back on
3) Write Calibrate only
3) Turn off ignition, turn back on and LEAVE it on in Run for 10 minutes
Came back and it fired, and put putted like a sack of ****, idling maybe 350 rpm..
So figuring I'd get rid of all the variables, I loaded the previous stock(ish) MAF tune back on just like the steps above, and started it up and it caught and ran, but idled around 500rpm, and sounded like ****, but it ran. The turbo pipes got hot FAST so I think it was running pretty lean, because I just halfed the fuel pressure (stock 26 lb/hr @ 58 psi vs. my 52 lb/hr @ 43.5psi) for this quickie MAF tune test. Not sure if it was running on all cylinders either because the turbo wasn't spinning all that well, but might be because of the low and inconsistent idle.
SO back to basics. Taking my previous MAF tune and straight up converting it over to speed density and then just changing injector flow values, then will see how that runs and take it from there!
As per internet reading I think I didn't do the proper Write sequence on the PCM, so I started from scratch and did:
1) Write Entire of speed density tune
2) Turn off ignition, turn back on
3) Write Calibrate only
3) Turn off ignition, turn back on and LEAVE it on in Run for 10 minutes
Came back and it fired, and put putted like a sack of ****, idling maybe 350 rpm..
So figuring I'd get rid of all the variables, I loaded the previous stock(ish) MAF tune back on just like the steps above, and started it up and it caught and ran, but idled around 500rpm, and sounded like ****, but it ran. The turbo pipes got hot FAST so I think it was running pretty lean, because I just halfed the fuel pressure (stock 26 lb/hr @ 58 psi vs. my 52 lb/hr @ 43.5psi) for this quickie MAF tune test. Not sure if it was running on all cylinders either because the turbo wasn't spinning all that well, but might be because of the low and inconsistent idle.
SO back to basics. Taking my previous MAF tune and straight up converting it over to speed density and then just changing injector flow values, then will see how that runs and take it from there!