{"product_id":"afm-dfm-vcm-disabler-pontiac-grand-prix-2005-2008-afm-dfm-disabler","title":"Pontiac Grand Prix 2005-2008 3.9L\/5.3L V6\/V8 AFM\/DFM Disabler","description":"\u003cp\u003eThis AFM\/DFM disabler plugs into the OBD-II port of the 2005–2008 Pontiac Grand Prix. Its job is to keep the engine running on all cylinders instead of dropping into the reduced-cylinder mode that GM's Active Fuel Management uses at light load. No tools, no wiring and no reflash of the engine computer. Unplug it and AFM works again as it did from the factory.\u003c\/p\u003e\u003ch2\u003eWhat it fits\u003c\/h2\u003e\u003cp\u003eThe fitment table for this part (all rows marked 100% fitment match):\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e2005–2006 Pontiac Grand Prix: 5.3L V8\u003c\/li\u003e\n\u003cli\u003e2007 Pontiac Grand Prix: 5.3L V8 \/ 3.9L V6\u003c\/li\u003e\n\u003cli\u003e2008 Pontiac Grand Prix: 5.3L V8\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eFor reference, these are the AFM-equipped GM engine codes that match the years and displacements above:\u003c\/p\u003e\u003cul\u003e\u003cli\u003eLS4 (5.3L, 2005–2009, VIN 8th digit \"C\")\u003c\/li\u003e\u003c\/ul\u003e\u003cp\u003eIf your engine code is not in this list, email the VIN to support before ordering so we can confirm the application.\u003c\/p\u003e\u003ch2\u003eWhat AFM does on these engines\u003c\/h2\u003e\u003cp\u003eGM's Active Fuel Management turns a V8 into a V4 at light load by deactivating cylinders 1, 7, 6 and 4. Solenoids route oil pressure to the lifters on those cylinders, which collapse and stop opening the valves. Fuel to those cylinders is cut at the same time. Press the throttle harder and the system brings all eight back.\u003c\/p\u003e\u003ch2\u003eCheck the engine first\u003c\/h2\u003e\u003cp\u003eScan for stored codes before you plug it in. Misfire codes on the deactivation cylinders, an AFM solenoid circuit code, or a lifter noise are signs of an existing problem that should be repaired first. The module is meant for a healthy engine where you simply do not want cylinder deactivation.\u003c\/p\u003e\u003ch2\u003eWhat changes when you drive\u003c\/h2\u003e\u003cp\u003eThe difference shows up in light-load driving: steady highway speeds, gentle acceleration and coasting down small grades. Those are the moments when AFM used to drop cylinders. With the module in, engine behavior there should feel the same as under heavier throttle. Full-throttle performance does not change, because AFM was never active at full throttle anyway.\u003c\/p\u003e\u003ch2\u003ePlug-in module vs. a mechanical AFM delete\u003c\/h2\u003e\u003cp\u003eA mechanical AFM delete swaps the deactivating lifters (and often the camshaft and lifter oil manifold) for non-AFM parts and requires a tune afterwards. A tune alone can switch AFM off in software. This module works through the OBD-II port instead, so the engine hardware and its calibration stay stock. That makes it the easiest option to reverse, and the right one only when the engine is mechanically healthy.\u003c\/p\u003e\u003ch2\u003eKeep up with oil changes\u003c\/h2\u003e\u003cp\u003eDisabling cylinder deactivation does not replace normal maintenance. Use the oil grade and change interval GM lists for your engine, watch the oil level between changes, and repair leaks promptly. The valvetrain on these engines depends on clean oil at proper pressure in every mode.\u003c\/p\u003e\u003ch2\u003eUsing it day to day\u003c\/h2\u003e\u003cp\u003eThe module uses the OBD-II port, so it has to come out whenever a technician or an inspection station needs the port. Plugging it back in restores the all-cylinder mode. Route it so the driver cannot kick it loose.\u003c\/p\u003e\u003ch2\u003eWhy people turn AFM off\u003c\/h2\u003e\u003cp\u003eOwners usually disable AFM for one of three reasons: they notice the change between modes as a vibration or exhaust drone, they want a consistent throttle response while towing or climbing grades, or they want to limit how often the deactivation lifters switch. Keeping the engine on all cylinders addresses all three. The tradeoff is that you give up whatever fuel saving AFM was providing in light cruising.\u003c\/p\u003e\u003ch2\u003eConfirm your engine\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eYour model year, model and engine match a row in the table (2005–2008 Pontiac Grand Prix).\u003c\/li\u003e\n\u003cli\u003eFind your engine code. On GM vehicles before the 2018 model year, the Service Parts Identification label (usually inside the glovebox on these trucks and SUVs) lists the three-character RPO codes, and the engine code starts with L. From 2018, GM moved that data into a QR code on the certification label on the driver-side door pillar. The 8th character of the VIN also identifies the engine.\u003c\/li\u003e\n\u003cli\u003eNo check-engine light is on, and oil level and pressure are normal.\u003c\/li\u003e\n\u003cli\u003eEngine swaps, custom tunes and replaced ECUs need a fitment check from support before ordering.\u003c\/li\u003e\n\u003cli\u003eQuestions: support@automotivebypass.com with your VIN.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eYear-by-year fitment\u003c\/h2\u003e\u003cp\u003eEach model year from the fitment data, with the AFM engine codes GM used for that year and displacement:\u003c\/p\u003e\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eYear\u003c\/th\u003e\n\u003cth\u003eMake\u003c\/th\u003e\n\u003cth\u003eModel\u003c\/th\u003e\n\u003cth\u003eEngine\u003c\/th\u003e\n\u003cth\u003eAFM codes\u003c\/th\u003e\n\u003cth\u003eListing note\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e2005\u003c\/td\u003e\n\u003ctd\u003ePontiac\u003c\/td\u003e\n\u003ctd\u003eGrand Prix\u003c\/td\u003e\n\u003ctd\u003e5.3L V8\u003c\/td\u003e\n\u003ctd\u003eLS4\u003c\/td\u003e\n\u003ctd\u003e100% Fitment Match | OEM-Grade Quality | Plug \u0026amp; Play\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e2006\u003c\/td\u003e\n\u003ctd\u003ePontiac\u003c\/td\u003e\n\u003ctd\u003eGrand Prix\u003c\/td\u003e\n\u003ctd\u003e5.3L V8\u003c\/td\u003e\n\u003ctd\u003eLS4\u003c\/td\u003e\n\u003ctd\u003e100% Fitment Match | OEM-Grade Quality | Plug \u0026amp; Play\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e2007\u003c\/td\u003e\n\u003ctd\u003ePontiac\u003c\/td\u003e\n\u003ctd\u003eGrand Prix\u003c\/td\u003e\n\u003ctd\u003e5.3L V8 \/ 3.9L V6\u003c\/td\u003e\n\u003ctd\u003eLS4\u003c\/td\u003e\n\u003ctd\u003e100% Fitment Match | OEM-Grade Quality | Plug \u0026amp; Play\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e2008\u003c\/td\u003e\n\u003ctd\u003ePontiac\u003c\/td\u003e\n\u003ctd\u003eGrand Prix\u003c\/td\u003e\n\u003ctd\u003e5.3L V8\u003c\/td\u003e\n\u003ctd\u003eLS4\u003c\/td\u003e\n\u003ctd\u003e100% Fitment Match | OEM-Grade Quality | Plug \u0026amp; Play\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003ch2\u003eBefore you plug it in\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eScan the engine for stored codes and note any misfire or AFM solenoid codes.\u003c\/li\u003e\n\u003cli\u003eCheck the oil level and confirm the grade matches GM's specification for your engine.\u003c\/li\u003e\n\u003cli\u003eSwitch the ignition off before inserting the module.\u003c\/li\u003e\n\u003cli\u003eLocate the OBD-II port under the driver-side dash.\u003c\/li\u003e\n\u003cli\u003ePush the module in until it is fully seated and sits clear of your knee and the pedals.\u003c\/li\u003e\n\u003cli\u003eStart the engine and let it idle before driving.\u003c\/li\u003e\n\u003cli\u003eTake a drive at steady light throttle, where AFM used to engage, and confirm the engine stays on all cylinders.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eA short history of GM cylinder deactivation\u003c\/h2\u003e\u003cp\u003eGM first sold cylinder deactivation in 1981 with the Cadillac V8-6-4. The modern system was announced in 2003 as Displacement on Demand and reached production on the 2005 Chevrolet TrailBlazer EXT and GMC Envoy XL and XUV with the 5.3L V8, followed by the 5.3L LS4 in the Impala SS, Monte Carlo SS and Pontiac Grand Prix GXP. Renamed Active Fuel Management, it spread across GM's Gen IV and EcoTec3 truck engines. For the 2019 Silverado, GM introduced Dynamic Fuel Management, based on Tula Technology's Dynamic Skip Fire, which can deactivate cylinders individually.\u003c\/p\u003e\u003ch2\u003eQuick definitions\u003c\/h2\u003e\u003cp\u003e\u003cstrong\u003eVIN 8th digit:\u003c\/strong\u003e The VIN character that identifies the engine.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eOBD-II port:\u003c\/strong\u003e The standard diagnostic connector under the dash on every US vehicle since 1996.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eAFM:\u003c\/strong\u003e Active Fuel Management, GM's cylinder deactivation system on the engines covered here.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDoD:\u003c\/strong\u003e Displacement on Demand, the original name for AFM.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eSPID label:\u003c\/strong\u003e Service Parts Identification label listing the RPO codes on pre-2018 GM vehicles.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eRPO code:\u003c\/strong\u003e GM's three-character option code; engine codes begin with L.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eDFM:\u003c\/strong\u003e Dynamic Fuel Management, the system on 2019-on L84 and L87 engines that can deactivate cylinders individually.\u003c\/p\u003e\u003ch2\u003ePublished ratings for these engines\u003c\/h2\u003e\u003cp\u003eRatings and features for the engine codes that apply to this listing, as published for each engine (figures vary by vehicle and year):\u003c\/p\u003e\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eRPO code\u003c\/th\u003e\n\u003cth\u003eSize\u003c\/th\u003e\n\u003cth\u003ePower\u003c\/th\u003e\n\u003cth\u003eTorque\u003c\/th\u003e\n\u003cth\u003eCompression\u003c\/th\u003e\n\u003cth\u003eNotes\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\u003ctr\u003e\n\u003ctd\u003eLS4\u003c\/td\u003e\n\u003ctd\u003e5.3L\u003c\/td\u003e\n\u003ctd\u003e300–303 hp\u003c\/td\u003e\n\u003ctd\u003e323 lb-ft\u003c\/td\u003e\n\u003ctd\u003e10.00:1\u003c\/td\u003e\n\u003ctd\u003ealuminum block, AFM, front-wheel drive\u003c\/td\u003e\n\u003c\/tr\u003e\u003c\/tbody\u003e\n\u003c\/table\u003e\u003ch2\u003eThe hardware behind AFM\u003c\/h2\u003e\u003cp\u003eAFM uses oil pressure as its control signal. A solenoid valve assembly under the intake manifold, in the valley cover, routes oil to collapsible lifters on the deactivating cylinders. Aerated or wrong-viscosity oil slows that signal. Keeping AFM off removes the switching, but every lifter still relies on the oiling system, so stick to the specified oil and intervals.\u003c\/p\u003e\u003ch2\u003eAbout these engine codes\u003c\/h2\u003e\u003cul\u003e\u003cli\u003e\n\u003cstrong\u003eLS4\u003c\/strong\u003e: 5.3L V8 mounted transversely in front-drive cars such as the Impala SS, Monte Carlo SS and Grand Prix GXP. VIN engine digit \"C\".\u003c\/li\u003e\u003c\/ul\u003e\u003ch2\u003eAfter-install checks\u003c\/h2\u003e\u003cp\u003e\u003cstrong\u003eWarning light appears:\u003c\/strong\u003e Remove the module, scan for codes and email support with the code and VIN.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eMode changes still felt:\u003c\/strong\u003e Re-seat the module and confirm your engine code is on the AFM list for this listing.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eShop cannot reach the diagnostic port:\u003c\/strong\u003e Unplug the module for the visit and refit it afterwards.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eLifter noise or misfire codes:\u003c\/strong\u003e These point to existing engine faults that need diagnosis and repair.\u003c\/p\u003e\u003ch2\u003eQuestions owners ask\u003c\/h2\u003e\u003ch3\u003eWill it fix lifter noise or misfires?\u003c\/h3\u003e\u003cp\u003eNo. Those are mechanical or electrical faults that need their own diagnosis and repair.\u003c\/p\u003e\u003ch3\u003eDoes it plug into the OBD-II port on the Pontiac Grand Prix?\u003c\/h3\u003e\u003cp\u003eYes. It plugs into the OBD-II port under the dash. There is no wiring or splicing.\u003c\/p\u003e\u003ch3\u003eWhich Pontiac Grand Prix years and engines does it fit?\u003c\/h3\u003e\u003cp\u003eThe fitment table lists Pontiac Grand Prix 2005–2008 with 3.9L V6, 5.3L V8. Match your exact year and engine to a row before ordering.\u003c\/p\u003e\u003ch3\u003eDo I need to remove it for an emissions test or scan tool?\u003c\/h3\u003e\u003cp\u003eYes. It uses the diagnostic port, so unplug it while the port is needed and plug it back in afterwards.\u003c\/p\u003e\u003ch3\u003eIs a tune or ECU reflash required?\u003c\/h3\u003e\u003cp\u003eNo. The module plugs into the OBD-II port and does not rewrite the engine computer's software.\u003c\/p\u003e\u003ch3\u003eDoes it change anything when towing?\u003c\/h3\u003e\u003cp\u003eUnder heavy load, such as towing up a grade, AFM already keeps all cylinders running. The difference shows up during lighter cruising between climbs, where the engine no longer drops cylinders.\u003c\/p\u003e\u003ch3\u003eDoes it work on 2019 and newer trucks with Dynamic Fuel Management?\u003c\/h3\u003e\u003cp\u003eOnly the vehicles and engines in this listing's fitment table are covered. DFM on the 2019-on Silverado 1500 and Sierra 1500 (5.3L L84, 6.2L L87) is a different system, so do not assume coverage outside the table.\u003c\/p\u003e\u003ch3\u003eHow do I tell which engine my Pontiac Grand Prix has?\u003c\/h3\u003e\u003cp\u003eCheck the 8th digit of the VIN or the RPO codes on the Service Parts Identification label (QR code on the door-pillar label on 2018 and newer GM models).\u003c\/p\u003e\u003ch3\u003eWill it add horsepower?\u003c\/h3\u003e\u003cp\u003eNo. It keeps all cylinders active; it does not change the engine tune.\u003c\/p\u003e\u003ch3\u003eCan I go back to factory AFM?\u003c\/h3\u003e\u003cp\u003eYes. Unplug the module and the factory cylinder-deactivation strategy works again.\u003c\/p\u003e\u003ch3\u003eHow much fuel does AFM save?\u003c\/h3\u003e\u003cp\u003eEPA-test estimates published for GM's system are about 5.5–7.5%, with the benefit coming from light-load cruising. Keeping all cylinders active gives up part of that, depending on how you drive.\u003c\/p\u003e\u003ch3\u003eDo I need it if my engine already has an AFM delete?\u003c\/h3\u003e\u003cp\u003eNo. An engine with the AFM hardware removed and a matching tune no longer deactivates cylinders, so the module has nothing to manage.\u003c\/p\u003e\u003ch2\u003eShipping and support\u003c\/h2\u003e\u003cp\u003eShipping is free to the contiguous US. Orders leave in 1–2 business days and usually arrive 3–4 business days later. Returns are accepted within 45 days with pre-approval; a 20% restocking fee applies and the buyer covers return shipping. The part carries a 3-year limited warranty, and support@automotivebypass.com answers Monday to Friday, 9–5 Pacific.\u003c\/p\u003e","brand":"Automotivebypass","offers":[{"title":"Default Title","offer_id":56493787021684,"sku":"RC-AFM-DFM-01-37","price":79.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1030\/8439\/2820\/files\/RC-AFM-DFM-01-37-1.jpg?v=1793172543","url":"https:\/\/automotivebypass.com\/products\/afm-dfm-vcm-disabler-pontiac-grand-prix-2005-2008-afm-dfm-disabler","provider":"Automotivebypass","version":"1.0","type":"link"}