This blog post recounts the experience of troubleshooting a 1967 Shelby GT350 during the Colorado Shelby Rally. The car faced power issues while ascending Pikes Peak, leading to a detailed investigation into fuel delivery problems. After multiple attempts and consultations with the manufacturer, the team identified a faulty fuel pump as the root cause, ultimately resolving the issue and successfully driving to the summit.
Driving a classic car like the 1967 Shelby GT350 up Pikes Peak is a dream for many automotive enthusiasts. However, when a customer's newly restored vehicle starts losing power during a mountain ascent, it turns into a troubleshooting adventure. This blog post details the experience of diagnosing and fixing a fuel delivery issue in a Revology Resto mod GT350 during the Colorado Shelby Rally.
In June, during the Colorado Shelby Rally, a gathering of car enthusiasts, we were excited to provide roadside support while enjoying the stunning Colorado scenery. The customer had recently received their 1967 Shelby GT350 Resto mod from Revology, having already driven it for about 3,000 miles without issues. This rally was to be the first time the customer would take the car over a mountain pass.
As we began our ascent, everything seemed perfect until we noticed the GT350 pulling over with its hazard lights on. Upon inspection, the customer reported that the car was losing power and unable to climb the mountain. This was the first issue the customer had experienced with the vehicle, which had performed flawlessly until this point.
Given that this was a modern Resto mod with fuel injection, troubleshooting was different from what it would have been for an original carbureted model. I had brought along a Snap-On scanner, which revealed a fuel delivery error code. After restarting the car, it seemed to run fine, leading us to suspect a possible fuel pump issue.
We decided to return to the last town to find a replacement fuel pump. However, upon meeting the customer again, he reported that the car was running perfectly, with no error codes. We cleared the codes and attempted the mountain pass again, but the car failed at the same spot, pulling over with hazard lights flashing.
After several attempts and resets by disconnecting the battery, we concluded that the issue was likely related to the car's computer rather than the fuel pump. The car would run fine at lower elevations but struggled at higher altitudes, indicating a potential problem with the engine management system.
We reached out to Revology for assistance. Their customer service was commendable, as they responded promptly despite the late hour. They informed us that other customers had experienced similar issues with the engine and computer at high elevations, aligning with our findings.
After a couple of months, the car returned to the shop for further evaluation. The tuner made some adjustments, and we decided to test the vehicle on Pikes Peak, which rises to over 14,000 feet. As we ascended, we monitored the altimeter closely, noting that the trouble spot seemed to be between 10,000 and 12,500 feet.
As we reached higher elevations, the car began to exhibit the same power loss symptoms. We recorded the data and sent it to the tuner, who identified a drop in fuel pressure. This led us to suspect that the fuel cap might be causing a vacuum issue, so we removed it for the next stretch of the drive.
With the fuel cap off, we made another attempt to reach the summit. This time, we were able to drive full throttle without any issues, successfully reaching the top of Pikes Peak. We celebrated our achievement, believing we had resolved the problem.
After descending to 10,000 feet, we decided to try the ascent again. This time, we encountered minimal traffic, allowing us to perform several wide-open throttle pulls without any problems. The car was finally running as it should, confirming that the fuel pump replacement had solved the issue.
Reflecting on the entire experience, it became clear that had we replaced the fuel pump during the initial breakdown, the customer could have completed the rally without further complications. The moral of the story is to trust your instincts when diagnosing automotive issues. Sometimes, the simplest solution is the most effective.
The journey of troubleshooting the 1967 Shelby GT350 was filled with challenges and learning opportunities. From initial breakdowns to successful ascents, this experience highlighted the importance of thorough diagnostics and the value of expert support. Ultimately, the car was able to conquer Pikes Peak, proving that with persistence and the right approach, even the most daunting challenges can be overcome.
