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No acceleration to pass (LY6)

The fuel volume test can be a bit tricky, you will need to know your specs which I don't know. However if you know the rated output of your fuel pump you can get an idea if you at least meet the pumps rated volume. For example if your pump is 40 gallons per hour multiply that by 16 and get 640 cups per hour. Divide 640 by 3600 to get 0.17778 cups per second. Times 30 to get 5.3334 cups in 30 seconds. Then you would use a stop watch for 30 seconds and measure the volume of fuel into a safe container. Your TPS voltages you would also need to locate your specs. If you are throttle by wire there should be specs on that to insure that the throttle is indeed opening in accordance to how much you move the pedal.
 
I'd suspect fuel delivery too. Pressure is good, but if you don't have the volume it's going to fall on its face. The o2 sensors should be a good indicator of what is going on. If the volume is off, the sensors should be going lean. Fuel trim values will trend lean too. It should be setting fuel trim codes if it's way out of whack for sure. Have you pulled codes yet?

The maf relocation should help but I don't think it's the primary issue.
 
I'd suspect fuel delivery too. Pressure is good, but if you don't have the volume it's going to fall on its face. The o2 sensors should be a good indicator of what is going on. If the volume is off, the sensors should be going lean. Fuel trim values will trend lean too. It should be setting fuel trim codes if it's way out of whack for sure. Have you pulled codes yet?

The maf relocation should help but I don't think it's the primary issue.

I have checked with an obd scanner and have no codes. I will check on the fuel volume next week after I get back from training for work.
 
I have checked with an obd scanner and have no codes. I will check on the fuel volume next week after I get back from training for work.
Even without codes watching the O2 data while driving would lend some insight on the issue. If you have the access to a scan tool or some type of data logger.
 
Even without codes watching the O2 data while driving would lend some insight on the issue. If you have the access to a scan tool or some type of data logger.

I do not have access to a Data logger and I don't know how to use one myself. I will check with my friend to see if his scanner is capable of that type of information and give it a shot after my trip. I appreciate your advice and direction on this because with my lack of experience I would be completely lost keep replacing parts that probably don't need replaced
 
You don't need HPtuner to scan and log. Just grab a $25 ELM bluetooth adapter and $5 for Torque on a smartphone. Then you can scan throttle position, TPS, MAF, MAP, everything. Might find the problem right away.
 
You don't need HPtuner to scan and log. Just grab a $25 ELM bluetooth adapter and $5 for Torque on a smartphone. Then you can scan throttle position, TPS, MAF, MAP, everything. Might find the problem right away.

I'll check that out. Sounds like the least expensive way to get some info I need. Thanks
 
When you say dogs out, do you mean like falls on face with no throttle response until rpms drop down then comes back to life? I had similar issue with my ly6 where it would only rev to 4k then fall on its face with no throttle rey until rpms and speed goes back down to almost idle. Ended up needing custom tune because of the VVT. But I also have th400.
 
When you say dogs out, do you mean like falls on face with no throttle response until rpms drop down then comes back to life? I had similar issue with my ly6 where it would only rev to 4k then fall on its face with no throttle rey until rpms and speed goes back down to almost idle. Ended up needing custom tune because of the VVT. But I also have th400.

Hard to explain but I'd say the rpms drop and doesn't rev. After relocating the Maf it seems if I floor it it'll hesitate then launch but when it finally goes it sounds like the rpms are high. Gonna install a tach and see what the rpms are doing. Could be that I'm just not used to the sound of a flowmaster 40.
 
You don't need HPtuner to scan and log. Just grab a $25 ELM bluetooth adapter and $5 for Torque on a smartphone. Then you can scan throttle position, TPS, MAF, MAP, everything. Might find the problem right away.

Could you recommend a specific elm? Anything under $100. I'm finding quite a few when I search and don't want to get a bad one.
 
Just Google torque engine diagnostics and management app for whatever phone you have. It can read and clear codes and give you rpms, coolant temp, vacuum and other readings too
 
Could you recommend a specific elm? Anything under $100. I'm finding quite a few when I search and don't want to get a bad one.
This is what I use and it always works.

https://www.amazon.com/gp/product/B005NLQAHS/

https://play.google.com/store/apps/details?id=org.prowl.torque&hl=en_US

You can set up pages of dashboard with gauges or graphs of the signals. You can also store datalogs while you drive. If there are signals you can't find (like Knock retard), you may need to install an extra GM PID set, which can be found in the configuration settings.
 
Pretty similar to the device I got. But it's in my S10 back in Denver. So it's not available to take a pic of.
 
If your TPS or TAC was the issue you would register a code. And on your scanner the two TPS reading would not agree. Does run rich or she cut out or misfire at all? Check your coil harnesses and engine grounds. Specially the ground connection in the back of the bank 2 (passenger side) cylinder head and the one under the bank one exhaust manifold on the engine block. Also wouldn't hurt to check for vacuum and exhaust leaks. Exhaust leaks upstream of your O2 sensors will raise hell with your mixture.
 
Does run rich or she cut out or misfire at all? Check your coil harnesses and engine grounds. Specially the ground connection in the back of the bank 2 (passenger side) cylinder head and the one under the bank one exhaust manifold on the engine block. Also wouldn't hurt to check for vacuum and exhaust leaks. Exhaust leaks upstream of your O2 sensors will raise hell with your mixture.

Doesn't run rich (and I don't smell fuel or have any exhaust smoke of any color). I will check the other items you mentioned when I get home tomorrow. Pretty sure my grounds we're good. I saw enough ground issues while reading for this build that I may have gone overboard with grounding but I will check their connection points again.
 
Hooked up the scan tool, the one recommended by Blue85, and went for a ride. However, I did not know how to set it up to log data or what data to log and assumed it just logged it for me. So I'll try again tomorrow. On the plus side, the rpms were much lower then I thought they were. Still dogging at different throttle positions.
 
From the Torque main screen, go into settings (the gear logo) and you'll find a setting for logging and upload. You have to tell it which signals to log, though. Then when running you tell it when to start and stop logging.

Fir realtime display, you could start with something like this.

screenshot.jpg
 

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