I am not sure whether my readers are bored to tears with me recounting my Bluebird restomod disasters or overjoyed they don’t have to deal with these problems! However, the Bluebird restomod will be the subject once again of my monthly dissertation on progress (or lack thereof) on this project. I was prepared to claim total victory on the completion of the restomod. There would still be one loose end in getting the aftermarket cruise control operational, but that is rather secondary as I can never use it for my local driving or even for rod tours, which is about all I intend to do.
The replacement power disk brakes are installed and seating in; they work great now that the reason for a low pedal was discovered and corrected. You know the drill: “Pumping,” “Holding,” “Release,” “Got any more blue paper towels? I got fluid on the tires.” We knew that there was no air in the lines as we purged them about four times, both before and after driving. The reason for the low pedal turned out to be a very critical adjustment of the plunger in the dual power brake booster. A quarter inch meant the difference between a very low pedal and dragging brakes. Chalk up another lesson learned.
The sloppy handling was corrected by the installation of a stiffer front sway bar as well as the addition of a rear sway bar. Turned out that the factory front sway bar was totally loose on one side. Oops! Always be sure your nuts are tight before thinking the job is finished is a rule known by all mechanics. With the carefully balanced tires and tight handling, the car is really fun to drive as it is smooth and responsive.
John Cimbura helped with the final touches with installing the rear sway bar, and I volunteered to do a victory lap with him and his gearhead grandson. (“Honest Judge – I won’t do it again.”) The combination of the 420hp LS3 engine, racing differential, renewed and modified suspension, and six speed automatic transmission makes for a really kick ass drive!
THAT IS UNTIL THE DISASTER!
A few blocks from John’s house, I decided to run a mild emergency brake test on the downhill street. At 35mph, I jammed hard on the brake pedal and had a satisfying short stop, turned the corner, stepped on the gas and NOTHING. The engine quit running! I started it up, and the Bluebird will not go off idle with a dead gas pedal. It limped on idle to John’s driveway – I praised the Lord that it did not happen on South Broadway. This happened once before with no known cause. The LS3 is a “drive by wire” engine, which means that stepping on the gas pedal just sends a signal to the computer (ECU), which calculates a response to send to the electrical actuator that opens the throttle valve (imagine trying to walk with no spinal cord signals).
I opened the hood and checked for anything loose – all looked good. I deliberately designed the transmission console to give an easy, no-tool-access to the ECU.
In a minor fit of desperation, I reached in and wiggled the cables and connectors to the ECU, turned the key, and the engine ran normal. Something must be intermittently loose, perhaps a pin, a bad crimp, a broken wire, or a bad solder joint in the ECU, OR a veritable needle in the haystack. I am not a virgin when it comes to this problem as I have encountered it in my professional life when doing designs or system trouble shooting. I would rather have shrapnel and oil on the road than this problem. You can’t find it until it happens, and you can’t fix it until you find it, and it is working at the moment. The fact is the car is now unsafe to drive, which is a final insult to me by my Bluebird.
Like most problems in life, it is not going to fix itself. As a starting point, I consulted with Todd, the service manager at Elway Chevrolet. All the involved parts were purchased over the counter new at Elway; there are no junk yard parts on the car. Todd is a street rodder at heart and has been very responsive in helping me with problems. His advice: “Better call Jerry.” Jerry Price is my friend in Castle Rock who is the acknowledged super tech when it comes to GM service problems. I know that this problem is not going to be fixed by throwing some very expensive parts at it. Therefore, here’s what needs testing:
- Open all connectors and do pin pull tests to see if there is a loose female pin.
- Open both ends of cables and signal test with a light to see if there is signal loss or degradation.
- Check for bad wire insulation.
- Start going to church.
Doing these tests on the bench is not a bad job. Doing them bent under the dash of a car or reaching into a blind hole using a flashlight is a different matter. May try to make this happen by driving around the block with a tow strap in the car.
Until a definite cause is found and corrected, the Bluebird is under garage arrest and forbidden to travel. There is no need to give me some lip about using a carburetor. Will there be better news next month? I sure hope so!
PS: The way I would like to troubleshoot this problem is by using an oscilloscope to look at signals and see where there is a fault. In order to do this effectively, it is essential to have a schematic of the entire design. GM will only supply a wiring diagram, which is insufficient for this type of in-depth troubleshooting. That frustrates me, to say the least.