New HP User, Issue with 2010 Camaro SS Whipple hot start

[Hesster]

Really would appreciate help from the Forced Induction and Tuner Heavy weights on this maddening issue.

I am trying to root cause my start and die issue on my 2010 SS Whipple & Cam set up. Developed this condition over the last few years where the car is difficult to stay running after start-up, and can try to start 2-3+ times before it stays running. This year it went into P2135 limp mode after 6 start attempts, so I cleared the code and it would at least run normal when it started. I have had a well known tuner analyze many Data Logs and revise my tune, it is better, but still has the issue, especially when hot. He say's it can't be "Tuned Out", and is probably mechanical. When it runs, it really rips, but lot's of back rap and popping with the Long Tubes and Borla Atak w/o Cats. Normal? - I don't mind it. The start/stall issue is evident on the attached DL - one at the beginning, and 3 at the end, all have a short RPM spike.

Back Ground - new TB, Accel Pedal, New fully charged battery, new tune. No current Codes! Drained the old gas and put in fresh 93 Tier 2. Kept pumping fresh gas into old gas over a number of years as the car is basically infrequently driven (car shows, a romp, etc.) My Tuner said disconnect and bypass the MSD BAP, which I did. Used MSD View software to analyze it and it seemed to function OK, but bypassed it to rule it out. IAT readings seemed high (gage on VCM screen red after 110 deg), ranging from 61 deg cold to 118+ at hot idle? Insulated the CAI Air box some more, and wrapped the inlet tube. Inlet tube was warm and blower hat was hot after a drive - normal?

What I am doing now - checking and cleaning all grounds, wire harness integrity, connections, etc. Looking for the obvious. The car is immaculate and not like there is a lot of corrosion anywhere. My tuner said to check if my injectors were leaking. Getting a fuel pressure tester to do this. Is the FP Tap Port on the Whipple Fuel Rail as shown in the attached pic? Just connect to that, key it, and look for leak down over time? Also in the process of changing the TR7IX plugs, even though they look OK.

Possible Root Causes:
1. Bad Injectors leaking causing a hard start and excessive back rap/pop on decell?
2. Intermittent Fuel Pump issue? Did the MSD BAP not play nice with the FP?
3. Intercooler Pump intermittent? Seems to flow when looking into reservoir, but noticed the ground wire connection at the terminal was not in the best condition.
4. Bad Ground(s)?
5. WTF Else to check?

Appreciate any insight and recommendations!

[gtstorey]

I would start by adding part numbers for MAP sensor and injectors. Likely changed to larger injectors when supercharger was installed.

[Hesster]

Standard Whipple Kit and a BT Blower Cam, installed and tuned by a local performance shop in 2016. Stock MAP Sensor 15865791, and "(2010-2012) Whipple Camaro SC systems comes with Siemens Deka 63 lb/hr fuel injectors that are rated up to 80psi of fuel pressure".

[Alvin]

I can't open the file. Its locked it says.

Popping in decel is typically because of not enough timing in decel.

On the hard start.. look at fuel pressure in the scanner before you start. Somewhere around 85-90 psi most injectors won't open. your fuel pressure was pretty high on start up (82 psi). I had a 5 gen camaro with a whipple have a issue with vapor lock. I can't remember how we fixed it.

[Alvin]

The IAT is quite good for a supercharged/whipple car. Its normal to be a bit hotter than a NA car.

[Hesster]

Appreciate the input! More than I am getting on another Camaro Website. I did notice the really high 80+ psi fuel pressure before cranking it on that data log, it is the only instance on that DL, and always 58 - 60 on the other 5 DL's I have. How that is possible with a stock pump and no MSD BAP connected is not understood. Maybe vapor lock like you had?
Good to know on the IAT numbers.
Figured the Tune file is locked? Prob done by my tuner.

[Alvin]

The fuel is getting hot in the rail and boiling. Is how the pressure gets so high. The stock pump has a check valve in it to keep everything forward.

This might not be the issue.. but it's worth bringing up.

[gtstorey]

Appreciate the input! More than I am getting on another Camaro Website. I did notice the really high 80+ psi fuel pressure before cranking it on that data log, it is the only instance on that DL, and always 58 - 60 on the other 5 DL's I have. How that is possible with a stock pump and no MSD BAP connected is not understood. Maybe vapor lock like you had?
Good to know on the IAT numbers.
Figured the Tune file is locked? Prob done by my tuner.

To be fair, there wasn't a lot of actual data provided on Camaro5, just that you had a no start that you were chasing bad fuel and a DTC.

The high pressure tends to occur when there is a check valve in the system and the fuel gets hot while setting, causing to expand or even boil and increase pressure.

[Hesster]

To be fair, there wasn't a lot of actual data provided on Camaro5, just that you had a no start that you were chasing bad fuel and a DTC.

The high pressure tends to occur when there is a check valve in the system and the fuel gets hot while setting, causing to expand or even boil and increase pressure.

Yeah, that is true but I did not want to start the discussion with a flood of data, tends to get ignored.
It seems I have already chased a number of things, the code was easy, the MSD BAP contribution, old gas, pin out the Whipple Extension, new parts, etc.
My tuner also said, as well as forum members, get a better fuel pump and ditch the BAP. If that is a solution to my problem, sure, but would want to isolate that as the key contributor before spending $1K+.

The hot high pressure and vapor lock thing makes sense as a "cause" but what causes that?

[Alvin]

I use BAPs all the time with no issues.

[Proxses]

Control module voltage drops to zero. It's like the key is being turned off.
Stall.jpg

[Hesster]

Control module voltage drops to zero. It's like the key is being turned off.
Stall.jpg

I noticed that, and good catch AND, that is the case in EVERY start and stall instance. Something is killing the voltage. The question is WHAT could cause that.

[Proxses]

There was a TSB or recall related to cars shutting off from bumping the keys, or something of that nature. Maybe worn key cylinder?

[GHuggins]

I would check power and grounds on driver's fender - those get taken loose with engine removal. The key "fix" was to replace the fob/key combo with a regular ignition key and break the flip out key out of the fob so you couldn't use it anymore. Power drops can be from anything. Best to get a schematic and go from there.

[blindsquirrel]

Usually, GMs will set a code for power mode mismatch if it's a bad ignition switch, something that makes one of the outputs drop out while the others stay up. But if it's glitchy power to the switch input side, then all the outputs go down at the same time and, no codes set.

[Hesster]

There was a TSB or recall related to cars shutting off from bumping the keys, or something of that nature. Maybe worn key cylinder?

Unlikely - car is like new.

And update - did a fuel leak down test. They may be a little dirty given residual old fuel, but I think this leak down is not alarming and not the root cause of the issue.IMG_2274 r1.jpg

[gtstorey]

This car sets a lot. My guess is a damaged wire harness chewed by mice.

[blindsquirrel]

Unlikely - car is like new.

As somebody who spent way too many years at dealerships, I can tell you that more than once I have seen brand new cars being delivered that had to be pushed off the car carrier because of a crank-no-start.

[edcmat-l1]

Don't know if it's been mentioned here, but all 5th gens benefit from a ground cable installation from battery post to engine block. Any vehicle with a trunk mounted battery grounded to the body for that matter.

[pannetron]

You can't have too many ground straps between engine block, negative battery post, frame, and body. Even between each cylinder head and block. Make sure there is no paint between ground strap and metal surface.