{"id":530227,"date":"2026-07-17T12:20:16","date_gmt":"2026-07-17T16:20:16","guid":{"rendered":"https:\/\/www.fs1inc.com\/blog\/?p=530227"},"modified":"2026-07-19T11:41:06","modified_gmt":"2026-07-19T15:41:06","slug":"1999-gmc-sierra-c-k-series-pcm-replacement-guide","status":"publish","type":"post","link":"https:\/\/www.fs1inc.com\/blog\/1999-gmc-sierra-c-k-series-pcm-replacement-guide\/","title":{"rendered":"1999 GMC Sierra PCM Replacement Guide"},"content":{"rendered":"<div class=\"container\">\n<section class=\"hero\">\n<div class=\"code-badge\">PCM<\/div>\n<h1>1999 GMC Sierra PCM Replacement Guide<\/h1>\n<p class=\"hero-subtitle\">In the 1999 GMC Sierra, the Powertrain Control Module (PCM) manages engine timing, fuel injection, and transmission shifts. A faulty PCM can lead to misfires, stalling, or loss of communication with diagnostic tools.<\/p>\n<\/section>\n<div class=\"quick-summary\">\n<h2>Quick Summary<\/h2>\n<ul>\n<li>The PCM controls key engine and transmission functions.<\/li>\n<li>Replacements require precise electrical connections.<\/li>\n<li>Programming is mandatory after any PCM swap.<\/li>\n<li>Common failure codes include P0601 and P1631.<\/li>\n<li>Factory cautions emphasize careful handling to prevent damage.<\/li>\n<\/ul>\n<\/div>\n<div class=\"info-section\">\n<p>When a 1999 GMC Sierra displays erratic behavior\u2014such as a hard start, frequent stalling, or a sudden loss of power\u2014the Powertrain Control Module might be the culprit. This guide explains what the PCM does, why it matters, and how to replace it safely. You\u2019ll learn the exact steps to locate the module, the labor times involved, and the factory programming that follows a swap. By understanding these details, you can make an informed decision about whether to repair or replace the PCM, and how to keep your Sierra running smoothly.<\/p>\n<\/div>\n<div class=\"info-section\">\n<h2>What the PCM Does in a 1999 GMC Sierra (C\/K Series)<\/h2>\n<p>The Powertrain Control Module in the 1999 GMC Sierra integrates engine and transmission controls to deliver smooth operation. It receives data from sensors and sends commands to fuel injectors, ignition coils, and shift solenoids. A failure in the PCM can disrupt the timing of fuel delivery, cause improper shifting, or prevent the vehicle from starting altogether. <a href=\"https:\/\/www.fs1inc.com\/gm\/gmc-pcm-ecm-ecu-engine-computer\/sierra-c-k-series-engine-computers.html\">replacement engine computers for the Sierra 1999<\/a> for the correct application.<\/p>\n<\/div>\n<div class=\"info-section\">\n<h2>Where the PCM Is Located and What Replacement Involves<\/h2>\n<p>The PCM is located under the driver\u2019s seat, behind the dashboard. Removing the module involves disconnecting the battery, accessing the module with a flathead screwdriver, and lifting it out. Replacement requires re\u2011attaching the connector and securing the unit. According to the book times, the removal and installation of the PCM takes 0.8 hours for a gasoline engine and 1.4 hours for a diesel or larger Sierra models. No torque specifications are provided, so ensure the connector is firmly seated and the battery is re\u2011connected after the swap.<\/p>\n<figure style=\"margin:22px auto;text-align:center;max-width:720px\"><img decoding=\"async\" style=\"max-width:100%;height:auto;border:1px solid #e2e6ec;border-radius:8px\" src=\"https:\/\/www.fs1inc.com\/blog\/wp-content\/uploads\/2026\/07\/1999-gmc-sierra-c-k-series-pcm-service-figure.webp\" alt=\"1999 GMC Sierra (C\/K Series) PCM location diagram\" loading=\"lazy\"\/><figcaption style=\"font-size:13px;color:#667085;margin-top:8px\">From the factory PCM removal procedure for the 1999 GMC Sierra (C\/K Series).<\/figcaption><\/figure>\n<div style=\"background:#f7f9fc;border:1px solid #e2e8f2;border-radius:10px;padding:18px 24px;margin:18px 0\">\n<h3 style='margin-top:0'>How to Reach the PCM on the 1999 GMC Sierra (C\/K Series)<\/h3>\n<ol style=\"margin:14px 0 6px 0;padding-left:26px\">\n<li style=\"margin:10px 0;line-height:1.65\"><b>Remove<\/b> any debris from the PCM connector surfaces before.<\/li>\n<li style=\"margin:10px 0;line-height:1.65\"><b>Release<\/b> the PCM cover mounting holes (1, 5) away from the.<\/li>\n<li style=\"margin:10px 0;line-height:1.65\"><b>Release<\/b> the PCM cover from the mounting bracket.<\/li>\n<li style=\"margin:10px 0;line-height:1.65\"><b>Remove<\/b> the PCM cover.<\/li>\n<li style=\"margin:10px 0;line-height:1.65\"><b>Disconnect<\/b> the PCM harness connectors.<\/li>\n<li style=\"margin:10px 0;line-height:1.65\"><b>Release<\/b> the spring latch from the PCM.<\/li>\n<li style=\"margin:10px 0;line-height:1.65\"><b>Release<\/b> the PCM mounting tabs from the PCM.<\/li>\n<li style=\"margin:10px 0;line-height:1.65\"><b>Remove<\/b> the PCM from the engine compartment.<\/li>\n<\/ol>\n<p style='margin:10px 0 0 0'><em>Work with the ignition off, and treat the module as static-sensitive: avoid touching the connector pins at any point.<\/em><\/p>\n<\/div>\n<table style=\"width:100%;border-collapse:collapse;margin:18px 0;font-size:15px\">\n<tr>\n<th style=\"border:1px solid #d6dbe3;background:#f2f5f9;padding:9px 12px;text-align:left\">Operation<\/th>\n<th style=\"border:1px solid #d6dbe3;background:#f2f5f9;padding:9px 12px;text-align:left\">Configuration<\/th>\n<th style=\"border:1px solid #d6dbe3;background:#f2f5f9;padding:9px 12px;text-align:left\">Book Time<\/th>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">Powertrain Control Module R&amp;R<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">GAS<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">0.8 hr<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">Powertrain Control Module R&amp;R<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">DIESEL<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">1.4 hr<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">Powertrain Control Module R&amp;R<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">Sierra 1500<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">1.4 hr<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">Powertrain Control Module R&amp;R<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">Sierra 2500<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">1.4 hr<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">Powertrain Control Module Relearn<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">C1500<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">0.5 hr<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">Powertrain Control Module Relearn<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">C1500 Suburban<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">0.5 hr<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">Powertrain Control Module Relearn<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">C2500<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">0.5 hr<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">Powertrain Control Module Relearn<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">C2500 Suburban<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">0.5 hr<\/td>\n<\/tr>\n<\/table>\n<\/div>\n<div class=\"info-section\">\n<h2>Programming Requirements After Replacement<\/h2>\n<p>After installing a new PCM, the factory procedure mandates EEPROM programming and a password learning sequence, specifically for the Theft Deterrent Start Enable Signal (P1631). Flagship One units arrive VIN\u2011programmed, so these steps are already completed. Therefore, the only action required is to verify the unit\u2019s readiness with a diagnostic scan. <a href=\"https:\/\/www.fs1inc.com\/1999-gmc-c-k-series-1500-5-0l-engine-computer-pcm-ecm-ecu-programmed-plug-play.html\">VIN\u2011programmed replacement unit<\/a> for the correct application.<\/p>\n<\/div>\n<div class=\"info-section\">\n<h2>Symptoms of a Failing PCM<\/h2>\n<p>A failing PCM in the 1999 GMC Sierra can cause a range of symptoms. Drivers may notice the engine won\u2019t start, stalls under load, or experiences rough idling. The vehicle may also trigger misfire codes or exhibit shifting irregularities. When the PCM loses communication, a scan tool will show no data or will display fault codes such as <a href=\"https:\/\/www.fs1inc.com\/blog\/dtc-p0601-internal-control-module-memory-checksum-error\/\">Powertrain Control Module Failure<\/a> along with other internal codes. These issues often manifest as a sudden loss of power or a warning light on the dash.<\/p>\n<\/div>\n<div class=\"info-section\">\n<h2>Module Trouble Codes on the 1999 GMC Sierra (C\/K Series)<\/h2>\n<p>The 1999 GMC Sierra\u2019s PCM can generate several internal trouble codes. These codes help pinpoint specific failures within the module\u2019s circuitry or communication pathways.<\/p>\n<table style=\"width:100%;border-collapse:collapse;margin:18px 0;font-size:15px\">\n<tr>\n<th style=\"border:1px solid #d6dbe3;background:#f2f5f9;padding:9px 12px;text-align:left\">Code<\/th>\n<th style=\"border:1px solid #d6dbe3;background:#f2f5f9;padding:9px 12px;text-align:left\">Meaning<\/th>\n<th style=\"border:1px solid #d6dbe3;background:#f2f5f9;padding:9px 12px;text-align:left\">Full Guide<\/th>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><a href=\"https:\/\/www.fs1inc.com\/blog\/dtc-p0601-internal-control-module-memory-checksum-error\/\" style=\"color:#0563C1;text-decoration:none;display:block;cursor:pointer\"><b>P0601<\/b><\/a><\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><a href=\"https:\/\/www.fs1inc.com\/blog\/dtc-p0601-internal-control-module-memory-checksum-error\/\" style=\"color:#1a2b49;text-decoration:none;display:block;cursor:pointer\">Internal memory checksum error<\/a><\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><a href=\"https:\/\/www.fs1inc.com\/blog\/dtc-p0601-internal-control-module-memory-checksum-error\/\" style=\"color:#0563C1\"><b><u>Full P0601 guide &rarr;<\/u><\/b><\/a><\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><a href=\"https:\/\/www.fs1inc.com\/blog\/dtc-p0602-control-module-programming-error\/\" style=\"color:#0563C1;text-decoration:none;display:block;cursor:pointer\"><b>P0602<\/b><\/a><\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><a href=\"https:\/\/www.fs1inc.com\/blog\/dtc-p0602-control-module-programming-error\/\" style=\"color:#1a2b49;text-decoration:none;display:block;cursor:pointer\">Control module programming error<\/a><\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><a href=\"https:\/\/www.fs1inc.com\/blog\/dtc-p0602-control-module-programming-error\/\" style=\"color:#0563C1\"><b><u>Full P0602 guide &rarr;<\/u><\/b><\/a><\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><a href=\"https:\/\/www.fs1inc.com\/blog\/dtc-p0604-internal-control-module-random-access-memory-ram-error\/\" style=\"color:#0563C1;text-decoration:none;display:block;cursor:pointer\"><b>P0604<\/b><\/a><\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><a href=\"https:\/\/www.fs1inc.com\/blog\/dtc-p0604-internal-control-module-random-access-memory-ram-error\/\" style=\"color:#1a2b49;text-decoration:none;display:block;cursor:pointer\">Internal RAM error<\/a><\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><a href=\"https:\/\/www.fs1inc.com\/blog\/dtc-p0604-internal-control-module-random-access-memory-ram-error\/\" style=\"color:#0563C1\"><b><u>Full P0604 guide &rarr;<\/u><\/b><\/a><\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><a href=\"https:\/\/www.fs1inc.com\/blog\/dtc-p0608-control-module-vss-output\/\" style=\"color:#0563C1;text-decoration:none;display:block;cursor:pointer\"><b>P0608<\/b><\/a><\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><a href=\"https:\/\/www.fs1inc.com\/blog\/dtc-p0608-control-module-vss-output\/\" style=\"color:#1a2b49;text-decoration:none;display:block;cursor:pointer\">Module-internal fault<\/a><\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><a href=\"https:\/\/www.fs1inc.com\/blog\/dtc-p0608-control-module-vss-output\/\" style=\"color:#0563C1\"><b><u>Full P0608 guide &rarr;<\/u><\/b><\/a><\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><a href=\"https:\/\/www.fs1inc.com\/blog\/dtc-p0650-mil-control-circuitopen\/\" style=\"color:#0563C1;text-decoration:none;display:block;cursor:pointer\"><b>P0650<\/b><\/a><\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><a href=\"https:\/\/www.fs1inc.com\/blog\/dtc-p0650-mil-control-circuitopen\/\" style=\"color:#1a2b49;text-decoration:none;display:block;cursor:pointer\">Module-internal fault<\/a><\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><a href=\"https:\/\/www.fs1inc.com\/blog\/dtc-p0650-mil-control-circuitopen\/\" style=\"color:#0563C1\"><b><u>Full P0650 guide &rarr;<\/u><\/b><\/a><\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><a href=\"https:\/\/www.fs1inc.com\/blog\/dtc-p0654-engine-rpm-output-circuitopen\/\" style=\"color:#0563C1;text-decoration:none;display:block;cursor:pointer\"><b>P0654<\/b><\/a><\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><a href=\"https:\/\/www.fs1inc.com\/blog\/dtc-p0654-engine-rpm-output-circuitopen\/\" style=\"color:#1a2b49;text-decoration:none;display:block;cursor:pointer\">Module-internal fault<\/a><\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><a href=\"https:\/\/www.fs1inc.com\/blog\/dtc-p0654-engine-rpm-output-circuitopen\/\" style=\"color:#0563C1\"><b><u>Full P0654 guide &rarr;<\/u><\/b><\/a><\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><b>P1626<\/b><\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">Module-internal fault<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">&mdash;<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><b>P1631<\/b><\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">Module-internal fault<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">&mdash;<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><b>P1635<\/b><\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">Module-internal fault<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">&mdash;<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><b>P1637<\/b><\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">Module-internal fault<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">&mdash;<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><b>P1639<\/b><\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">Module-internal fault<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">&mdash;<\/td>\n<\/tr>\n<\/table>\n<\/div>\n<div class=\"info-section\">\n<h2>Factory Service Bulletins Worth Knowing<\/h2>\n<p>Service Bulletin #99-06-04-053 details PCM reprogramming procedures that were issued on October 26, 1999. This bulletin references the need for EEPROM programming and password learning after a PCM replacement.<\/p>\n<table style=\"width:100%;border-collapse:collapse;margin:18px 0;font-size:15px\">\n<tr>\n<th style=\"border:1px solid #d6dbe3;background:#f2f5f9;padding:9px 12px;text-align:left\">Bulletin<\/th>\n<th style=\"border:1px solid #d6dbe3;background:#f2f5f9;padding:9px 12px;text-align:left\">Subject<\/th>\n<th style=\"border:1px solid #d6dbe3;background:#f2f5f9;padding:9px 12px;text-align:left\">What It Addresses<\/th>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\"><b>99-06-04-053<\/b><\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">Info &#8211; PCM Reprogramming &#8211; (Oct 26, 1999)<\/td>\n<td style=\"border:1px solid #d6dbe3;padding:9px 12px\">&mdash;<\/td>\n<\/tr>\n<\/table>\n<\/div>\n<div class=\"info-section\">\n<h2>Protecting the PCM in Your 1999 GMC Sierra (C\/K Series)<\/h2>\n<ul style=\"margin:14px 0 6px 0;padding-left:26px\">\n<li style=\"margin:10px 0;line-height:1.65\">Keep the battery\u2019s charging system within spec to avoid voltage spikes.<\/li>\n<li style=\"margin:10px 0;line-height:1.65\">Regularly inspect the PCM connector for corrosion or loose pins.<\/li>\n<li style=\"margin:10px 0;line-height:1.65\">Use proper grounding techniques when installing add\u2011on equipment.<\/li>\n<li style=\"margin:10px 0;line-height:1.65\">Avoid sudden voltage changes by using a surge protector.<\/li>\n<li style=\"margin:10px 0;line-height:1.65\">Address any fault codes immediately to prevent further damage.<\/li>\n<li style=\"margin:10px 0;line-height:1.65\">Maintain the integrity of connector seals to protect against moisture.<\/li>\n<\/ul>\n<\/div>\n<div class=\"info-section\">\n<h2>Frequently Asked Questions<\/h2>\n<h3>What does the PCM control in my 1999 GMC Sierra?<\/h3>\n<p>The PCM coordinates fuel injection, ignition timing, and transmission shifting to maintain optimal performance.<\/p>\n<h3>How long does a PCM replacement take on a 1999 GMC Sierra?<\/h3>\n<p>Book times indicate 0.8 hours for gasoline engines and 1.4 hours for diesel or larger models.<\/p>\n<h3>Do I need to reprogram the PCM after replacement?<\/h3>\n<p>Yes, the factory requires EEPROM programming and a password learning sequence, but Flagship One units are VIN\u2011programmed.<\/p>\n<h3>Which fault codes should I watch for?<\/h3>\n<p>Common internal codes include P0601, P0602, P0604, P0608, P0650, P0654, P1626, P1631, P1635, P1637, and P1639.<\/p>\n<h3>Can I use a generic PCM for my Sierra?<\/h3>\n<p>It is best to use a unit that is specifically designed for the 1999 GMC Sierra to ensure compatibility and reliability.<\/p>\n<\/div>\n<div class=\"info-section\">\n<p>If your 1999 GMC Sierra shows signs of PCM failure, you have options. A professional repair can address software glitches, while a refurbished replacement unit offers a cost\u2011effective alternative. Both approaches are compatible with your vehicle\u2019s specific module configuration and can restore reliable operation.<\/p>\n<figure style=\"margin:22px auto;text-align:center;max-width:720px\"><img decoding=\"async\" style=\"max-width:100%;height:auto;border:1px solid #e2e6ec;border-radius:8px\" src=\"https:\/\/www.fs1inc.com\/media\/wysiwyg\/googleshop\/gmtypeO\/gm-pcm-typeo-1.jpg\" alt=\"Refurbished VIN-programmed PCM for the 1999 GMC Sierra (C\/K Series)\" loading=\"lazy\"\/><figcaption style=\"font-size:13px;color:#667085;margin-top:8px\">A refurbished, VIN-programmed replacement PCM for the 1999 GMC Sierra (C\/K Series) from Flagship One.<\/figcaption><\/figure>\n<p>Flagship One stocks a <a href=\"https:\/\/www.fs1inc.com\/1999-gmc-c-k-series-1500-5-0l-engine-computer-pcm-ecm-ecu-programmed-plug-play.html\"><b>refurbished, VIN-programmed PCM for the 1999 GMC Sierra (C\/K Series)<\/b><\/a> with a lifetime warranty, free shipping and no core charge. The full <a href=\"https:\/\/www.fs1inc.com\/gm\/gmc-pcm-ecm-ecu-engine-computer\/sierra-c-k-series-engine-computers.html\">GMC Sierra (C\/K Series) module lineup<\/a> covers other engine configurations as well.<\/p>\n<\/div>\n<div class=\"info-section\">\n<h2>Final Thoughts<\/h2>\n<p>For the 1999 GMC Sierra, replacing or repairing the PCM can resolve starting issues, stalling, and misfires. Take the time to assess your vehicle\u2019s symptoms and choose the solution that best fits your needs.<\/p>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>If your 1999 GMC Sierra won\u2019t start or stalls, the PCM may be at fault. Follow cautionary steps to avoid damage and restore reliable operation.<\/p>\n","protected":false},"author":1,"featured_media":525697,"comment_status":"open","ping_status":"closed","sticky":false,"template":"elementor_header_footer","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[258,270],"tags":[52,68,1443],"class_list":["post-530227","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-car","category-gmc","tag-52","tag-gmc","tag-sierra-c-k-series"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.0 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>1999 GMC Sierra PCM Replacement Guide - Flagship One Blog<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.fs1inc.com\/blog\/1999-gmc-sierra-c-k-series-pcm-replacement-guide\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"1999 GMC Sierra PCM Replacement Guide - Flagship One Blog\" \/>\n<meta property=\"og:description\" content=\"If your 1999 GMC Sierra won\u2019t start or stalls, the PCM may be at fault. 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