GrilledC6

Good morning everyone! I recently purchased this vette and it was great, but it just started giving me some trouble and wanted to see if anyone maybe had any ideas. It is an 05 C6 with heads/cam/intake/exhaust and a tune.

So I was driving along the other weekend when all of a sudden I completely lost throttle and the car would break up real bad when I gave it any gas. I was able to limp the car home but it idles really rough and still not allowing me to give it any throttle.

The initial codes it was throwing were for the pedal/throttle position sensor. I replaced them and now I'm not getting any codes, but the problem still persists. The strangest thing is that it at least seems to idle a bit when the maf is unplugged, though it runs incredibly rich. When the maf is plugged in, it just idles at like 100-200 RPM until it dies. The car doesn't seem to respond to throttle, in fact, it dies when you give it any gas. Also seeing an intermittent Service Traction System message.

Things I've tried:

• new battery
• swapped maf with a known good unit
• swapped throttle body
• swapped acelerator pedal
• inspected plugs and wires
• checked all related fuses in both fuse boxes (plus made sure blue connectors were tight)

Next step is probably checking the injectors and fuel pressure at the rails.

1st vid shows what happens when maf is plugged in: https://www.youtube.com/watch?v=qW1a...ature=youtu.be
2nd vid shows what happens when maf is unplugged: https://www.youtube.com/watch?v=xgX4...ature=youtu.be
3rd vid just shows that TB is working as it should: https://www.youtube.com/watch?v=Jkfu...ature=youtu.be

Any ideas/help/input is appreciated. Thanks!

C5 Diag

Wow !!...welcome !!...no issues in 7 years of being a member so you’ve been lucky my friend !!...first off do you have a scan tool to look at some data pids ??...I really don’t like to diagnose just based on symptoms but the MAP sensor is one of the few sensors that will put the car in limp mode...if you have a scan tool we can look at some MAP values and see what you have going on there...the PCM may think the car is a thousand feet below sea level so it may be scheduling more fuel hence the rich smelling exhaust because unplugging the MAF puts the engine in speed density (MAP input).

seevi

Your going to need some data logging to determine issues.

GrilledC6

Update: Checked the pressure at the rail and it's pretty low:




So looks like that at least narrows down the possible issues

C5 Diag

What is the pressure ??...looks like 16 psi maybe...didn’t even think the car would start with that low of a pressure...is this key ON ???...do you know how to checks amperage with a DVOM ?...if so I would use the leads between pins 87 and 30 of the fuel pump relay and check current flow...your pump probably draws the same amount as mine key on...around 6 amps...most DVOM’s are limited to 10 amps so you should be OK...if amps low I would check pump power and grounds...if they are good and amperage is low your pump is toast...if you don’t know how to do a voltage drop check you can just clean the pump ground..I believe your ground is on the rear frame rail inboard of the left rear tire...someone correct me if I’m wrong...if amps are high you may have a plugged filter which should be part of the fuel pump assembly !!