LSJ Tuning Woes

Ghostknife

Ghostknife

Goblin Guru
I figured it would be best to move the issues I am having out of my build thread into this one. Might help someone else down the road.

Synopsys is Low Boost and Misfires. I reset all the parameters for the DTCs back to normal. I will try to get out in the AM before the rain hits to see if I get some codes.
 
Ghostknife

Ghostknife

Goblin Guru
Watching Goat Rope Garages videos, will HP Tuners only give me parameters that I can change? It seems I don't have a lot of options but maybe its since I'm on a newer version. It seems that it is going into Open Loop when decelerating, Also when all of the Misfire counts climb up
 

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Ghostknife

Ghostknife

Goblin Guru
@Gtstorey
Can you get the wideband into the logs?
I don't think I can, I will have to check to see if the AEM has the output. It was in the donor car when I bought it. I may end up having to buy an updated one worst case. I will look into it.

You do know that you want to copy the changes from a different tune into you tune file and to not try and just write the different file into your ECM?
I didn't know that, I am learning this as I go. So in the Editor, I would copy the data is the other tune and paste it into my tune? I have already saved a "first edit" tune so I have the backup to revert to.

I've seen some post on HPT forum that says to not use the SAE PID for any of the throttle position sensors on GM stuff. They didn't say what's the difference , just to never use the SAE PID.
I have taken out the SAE and put in the non-SAE version of the TPS for future monitoring
 
Ross

Ross

Goblin Guru
My AEM wideband allows me to log in HP Tuners.
But it has quite a few steps to do it.

I have:
AEM 30-0300 X-Series Wideband UEGO AFR Sensor Controller Gauge
HP Tuners MPVI2

Needed to buy:
F-ber Connector DB9 RS232 Female Serial 9 Pin Port
TRENDnet USB to Serial Converter, Connect a RS-232 Serial Device to a USB

If you have a newer MPVI then there are ways to connect that don't involve serial output going to USB then into your laptop with VCM Scanner.
 
Ghostknife

Ghostknife

Goblin Guru
Ross said:
My AEM wideband allows me to log in HP Tuners.
But it has quite a few steps to do it.

I have:
AEM 30-0300 X-Series Wideband UEGO AFR Sensor Controller Gauge
HP Tuners MPVI2

Needed to buy:
F-ber Connector DB9 RS232 Female Serial 9 Pin Port
TRENDnet USB to Serial Converter, Connect a RS-232 Serial Device to a USB

If you have a newer MPVI then there are ways to connect that don't involve serial output going to USB then into your laptop with VCM Scanner.
Click to expand...
Yes I have the MPVI2+, I’ll do some digging to see what is needed.
 
baustin

baustin

Well-Known Member
Something you might want to check that's outside hptuners data, based on what I just went through... Check your fuel pressure with a test gauge on the fuel rail.
My best guess is that my recent fuel pump regulator failed open and my pump wouldn't hold pressure, but I found out it was only a 43 psi pump instead of the 58-60 psi that an LSJ wants. When I discovered this I reinstalled my original pump to troubleshoot (it had a bad fuel level sensor so it wasn't going to stay in) and found the regulator had failed closed... It went right up to 70-80+ psi and kept climbing so I shut it all off.
Point being, there are some misfire reasons that hptuners won't log since the LSJ has no fuel pressure sensor channel unless I just couldn't find it.

With a brand new pump that sits right at 58-60 psi and holds 50-55 psi with the key off, my engine sounds muuuccch better but I think my fuel trims are now off from the data logs I just took and need to retune it some.

It seems pretty common for the LSJ style fuel pump regulator to fail and they are only sold as part of the full fuel pump assembly from what I found.

About the not having many options in hptuners, make sure you're in the 'advanced' view, not 'basic'.
 
G

Gtstorey

Goblin Guru
Can you get the wideband into the logs?
I don't think I can, I will have to check to see if the AEM has the output. It was in the donor car when I bought it. I may end up having to buy an updated one worst case. I will look into it.
It will depend on the model. The reason it needs to be in there is for a check on your narrow band o2 to see if they are failing causing the Open Loop-Fault mode


You do know that you want to copy the changes from a different tune into you tune file and to not try and just write the different file into your ECM?
I didn't know that, I am learning this as I go. So in the Editor, I would copy the data is the other tune and paste it into my tune? I have already saved a "first edit" tune so I have the backup to revert to.
Yes, copy the data from the compare file into existing file and save as new. Then write calibration back to your car.

I've seen some post on HPT forum that says to not use the SAE PID for any of the throttle position sensors on GM stuff. They didn't say what's the difference , just to never use the SAE PID.
I have taken out the SAE and put in the non-SAE version of the TPS for future monitoring[/QUOTE]
 
G

Gtstorey

Goblin Guru
Ghostknife said:
Watching Goat Rope Garages videos, will HP Tuners only give me parameters that I can change? It seems I don't have a lot of options but maybe its since I'm on a newer version. It seems that it is going into Open Loop when decelerating, Also when all of the Misfire counts climb up
Click to expand...
Make sure that you are in advanced mode, but the available tables will vary greatly from ECM to ECM. I don't know if Goat Rope has ever done anything on an LSJ. I think the basics principles are the same as earlier V8 LS stuff but there will be different tables available. The Turbo LNF stuff is totally different.

Be careful when talking about "decelerating", since to a lot of people this will mean completely off the gas and entering "Deceleration Fuel Cutoff (DFCO). I don't think that is when yours is entering "open loop-fault mode. I think you are still giving it some gas, just not accelerating. But I may have missed something in your log.
 
G

Gtstorey

Goblin Guru
Ross said:
My AEM wideband allows me to log in HP Tuners.
But it has quite a few steps to do it.

I have:
AEM 30-0300 X-Series Wideband UEGO AFR Sensor Controller Gauge
HP Tuners MPVI2

Needed to buy:
F-ber Connector DB9 RS232 Female Serial 9 Pin Port
TRENDnet USB to Serial Converter, Connect a RS-232 Serial Device to a USB

If you have a newer MPVI then there are ways to connect that don't involve serial output going to USB then into your laptop with VCM Scanner.
Click to expand...
There is someone on HPTuners forum that is getting close to releasing an adapter to make the AEM -30-0300/0310 act like the 0334 and be able to connect through the OBD2 connector for the older cars. It's getting close to release
AEM 30-0334-type direct OBDII wideband for older vehicles. Any takers ? (hptuners.com)
 
G

Gtstorey

Goblin Guru
baustin said:
Something you might want to check that's outside hptuners data, based on what I just went through... Check your fuel pressure with a test gauge on the fuel rail.
My best guess is that my recent fuel pump regulator failed open and my pump wouldn't hold pressure, but I found out it was only a 43 psi pump instead of the 58-60 psi that an LSJ wants. When I discovered this I reinstalled my original pump to troubleshoot (it had a bad fuel level sensor so it wasn't going to stay in) and found the regulator had failed closed... It went right up to 70-80+ psi and kept climbing so I shut it all off.
Point being, there are some misfire reasons that hptuners won't log since the LSJ has no fuel pressure sensor channel unless I just couldn't find it.

With a brand new pump that sits right at 58-60 psi and holds 50-55 psi with the key off, my engine sounds muuuccch better but I think my fuel trims are now off from the data logs I just took and need to retune it some.

It seems pretty common for the LSJ style fuel pump regulator to fail and they are only sold as part of the full fuel pump assembly from what I found.

About the not having many options in hptuners, make sure you're in the 'advanced' view, not 'basic'.
Click to expand...
I'm still new at HP Tuners, but looking at the log, I'm guessing that there are both issues with the tune and other mechanical/electrical issues. It's going to be hard to distinguish between the two.
 
Ghostknife

Ghostknife

Goblin Guru
Ok well went to a shop today just to get a second opinion on the tune. The guy was awesome!! Said pull it in and let’s see what’s going on. He reinstated the dtcs and I threw a P2119 code, which probably explained the weird pedal %’s. He licensed my mpvi to my ECU and ran diagnostics and looked over my logs. He explained a lot of info to me and broke it down to simple terms. Charged me $50. At this point I will put on the factory throttlebody and will further look into what will throw this code
 
Rauq

Rauq

Goblin Guru
Ghostknife said:
Ok well went to a shop today just to get a second opinion on the tune. The guy was awesome!! Said pull it in and let’s see what’s going on. He reinstated the dtcs and I threw a P2119 code, which probably explained the weird pedal %’s. He licensed my mpvi to my ECU and ran diagnostics and looked over my logs. He explained a lot of info to me and broke it down to simple terms. Charged me $50. At this point I will put on the factory throttlebody and will further look into what will throw this code
Click to expand...
Buy this guy a case of beer, he sounds like an awesome ally to have.
 
Ghostknife

Ghostknife

Goblin Guru
Rauq said:
Buy this guy a case of beer, he sounds like an awesome ally to have.
Click to expand...
when I get everything settled out I will definitely be using him for any needs that I have tuning wise. He was very excited to see one in person, He had only seen Matt’s from Demo Ranch before.
Steve @ Power Dynamics out of Port Huron, MI 810-689-8286.
 
Ghostknife

Ghostknife

Goblin Guru
Gtstorey said:
Some more research on the "open loop-fault" indicates that it might be the misfires causing the fault, not the fault causing the misfires. Of course then its hard to say what is causing the misfires. Is it mechanical/electrical or in the tune?

(1) How to Fix GM Open Loop Fuel System Fault Using HP Tuners 4.x - YouTube
Very Strange Cobalt LSJ Issue. PLEASE HELP! (hptuners.com)
Click to expand...
Well it would be an awesome surprise if it had cams in it, but I don't know that it does. I'll have to dig into this...
 
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