GMC Safari Engine Stalls: Fuel Regulator Issue Alert

I experienced very similar symptoms with my 2003 GMC Savana, sounds a lot like what you are describing. Having some experience with automotive repair, I recognized these classic signs of fuel delivery problems. After multiple episodes of rough idling and engine misfire, I took it to a workshop where they diagnosed a defective high pressure pump. The car maintenance bill came to 1510 Euro, including parts and labor. Since the repair, the engine has been running smoothly with no more stalling or power issues. The symptoms you describe, especially the stalling at idle and reduced power, strongly point to fuel system problems. However, to provide more specific guidance: Could you share: Any specific error codes from the check engine light, When do you notice the power loss most (highway, city driving, or both), Have you noticed any unusual fuel consumption patterns, Any unusual sounds from the engine bay, Have you had any recent fuel system maintenance These details would help determine if your issue matches what I encountered with the high pressure pump failure. Car maintenance issues like this can be complex, so the more information you can provide, the better we can assist.

Thanks for the follow-up. Had my latest service at 69881 KM. The engine trouble codes show P0172 and P0174, indicating a rich fuel mixture. The power loss happens mainly during city driving when the engine is warm. Car sensors also indicate inconsistent fuel pressure readings. Fuel consumption has increased by about 20% in the last month. The engine makes a slight whining noise under acceleration. No major fuel system maintenance done aside from filter changes during regular car maintenance intervals. Given these readings and your experience, sounds like I should get the fuel pressure checked professionally before replacing parts. The rough idling pattern matches your description exactly.

Based on those codes and symptoms you mentioned, it does sound nearly identical to what I experienced with my Savana. My engine also had that characteristic whining noise, which turned out to be directly related to the failing high pressure pump. The increased fuel consumption and car sensors showing inconsistent pressure readings are telltale signs of fuel injection system problems. In my case, the rich fuel mixture codes (P0172/P0174) were triggered by irregular fuel delivery, causing the rough idling and power issues. Before rushing to replace the high pressure pump though, have a professional check the fuel pressure regulator first. When I initially diagnosed my vehicle, the technician found the pressure regulator was actually working fine, despite similar symptoms. The root cause was the pump itself failing to maintain consistent pressure. A proper fuel system diagnostic should cost around 150 Euro, which is worth it to pinpoint the exact issue. Automotive repair costs can pile up quickly if you start replacing parts without confirming the diagnosis. Keep track of your fuel economy, in my experience, the consumption got progressively worse until the pump was replaced. The fact that yours jumped 20% suggests you caught it earlier than I did.

Thanks everyone for your help. After getting the diagnostic test done, turns out my fuel pressure regulator is failing, causing the rich mixture and engine misfire issues. The mechanic showed me the pressure readings and they were way off spec. The repair quote came in at 450 Euro for parts and labor, which seems reasonable considering the symptoms and diagnostic results. They mentioned this should resolve both the check engine warnings and the rough idle. Going ahead with the repair next week. The automotive repair shop also recommended updating my fuel system maintenance schedule to prevent similar issues. Will report back on how it goes, especially whether it fixes the increased fuel consumption issue. Really helped having your insights about checking the regulator before assuming it was the pump. Saved me from potentially replacing the wrong parts. Thanks for helping me understand these fuel system problems better.