Hi guys, I'll be as brief as possible,

While driving over the weekend on the highway for a short rip the car bogged hard once in 5th gear. I ignored it and chalked it up to the PCM relearning as the battery was disconnected while the car sat for the past week or so. On the way home it did it again but not as strong.

On Monday night I went for a drive and the same thing happened while on the highway, this time though I had a bad feeling and turned around to go home. As I was driving the dreaded "Service Engine Soon" came on and I believe "reduced power." As I pulled over on the highway the car died.

The car would crank but not turn over. Shortly after the battery died as I had my hazzard lights on. A friend came and gave me a boost and the car started. I nursed it home and tested the battery yesterday, and it turns out it was bad.

I replaced the battery last night and went for another drive and the issue began to happen again where it bogged a few times.

The car has a cam, head work, and a tune, but never had an issue like this ever.

What I did so far:
I checked the DIC, NO CODES.
Cleared all codes
Checked the battery terminals, they are good

I soured the forums and found people with similar issues but never did see a resolution. The last thing I want to be doing is chasing gremlins all summer. Any suggestions will be appreciated!!!

 

Moved to C5 Tech.

 

I will start with that when I get home, I will also clean my MAF, check battery grounds, and check plug wires. Appreciate the help good sir!!!

 

Plug wires aren't going to cause a no start issue. Don't spend much time there.

 

The no start issue was due to a dead battery. A new battery fix that but he still has the bogging issue.

 

Correct!

Its a new battery as of yesterday. I should mention that the bogging isn't constant, itt will do it at random.

 

Thought I would provide an update that may help others in the future...

My mechanic took a look at it last week and all grounds and leads looked good. Before getting to any sensor's he took a look at the vacuum hoses and while moving the hose on the passenger side that goes into the valve cover he saw that it was split in half where it attaches towards the end of the block. The minute he pulled it off it basically crumbled.

Once he replaced that hose he continued on and checked the hose that goes into the throttle body (not the PCV hose) and it was also split. He replaced both hoses and we went for a drive and the car seemed stable. I still need more seat time to make sure it's good but I hope this was my only issue causing moments of hesitation or bogging!

 

Factory maf programmed car. Could the cracks have been severe enough to prompt a vacuum leak scenario with unmetered air entering the tb aft of the maf?

 

Not sure. My car also H/C and tuned, so not sure if those would be contributing factors due to air requirements.

 

So it looks like I lied. While driving to get an oil change the car dies in the parking lot. No codes. I can hear the fuel pump working but not sure how much pressure its putting out. I haven't tested spark on all the banks but the car will crank but doesn't turn over.

 

Crank but doesn't turn over?
Not sure what that is meaning? Cranking = starter engaged and engine is turning over

Do you mean its not firing - aka cranking but not "starting up"
Or that the starter is not engaging and just spinning or clicking?

I had some bogging issues with a bad spark plug + bad spark plug wires, but it was consistent.

 

An ignition problem would be consistant and occur ALL the time Being that your issue happens randomly i would not suspect ignition especially if you do not hear or feel a misfire
I would stsrt with the fuel system---Check your fuel pressure at idle It should be above 50 PSI----Change your fuel filter is it is over 10 months old---
If you have a CAI often the MAF will get fouled from the oiled filter Clean your MAF with Brakeclean--- Make sure your air intake clamps are sealed good --NO vacuum leaks
Anyone with a data logger can isolate where the issues lie---but try these fixes 1st before you take the next stwp

 

Yes, it cranks but does not fire. I checked the plugs and wires and they seem fine. This time around the car didn't bog, the rpm's just dropped and died. Like before, no codes.

The mechanic is going to check the pressure later today. The MAF looked good and I couldn't see any other vacuum leaks that I haven't addressed. The fuel filter is old so going to start there and hope it turns out to be a simple fix.

Thanks

 

I briefly talked to my mechanic and he said he was able to start up the car this morning and it ran for 5 minutes then it died. Tried starting it again and it was intermittent. He is letting it cool off right now before checking fuel pressure and anything else.

I did some searching and found this thread which seems to mimic my exact symptoms, only difference being I have a new battery.

https://www.corvetteforum.com/forums...-stalling.html

On another note can a LMC5 bypass go bad? How do I check if that could be the problem?

 

So the mechanic found positive cable to the fuse panel was loose. Re-tightened everything, checked all the grounds and started it up. It ran fine, but once it hit 71c it died again. Apparently every time it hits 71c it dies. I have a crank position sensor that I will give him to try, but I'm running out of ideas.

 

No, HOWEVER, I found something on another forum that directly corresponds with my issue...

http://www.z06vette.com/forums/f5/en...79/index2.html

(Sorry if the link I posted is not allowed)

This guy had the exact same issue, and to make a long story short it was the crank position sensor. I just so happened to have one that I bought 5 years still in the package and dropped it off to the mechanic. HOPEFULLY this is the problem. I'll post when I know...

 

After changing the crank sensor I think I may have found success...sent by my mechanic...