{"id":518873,"date":"2025-12-11T02:13:46","date_gmt":"2025-12-11T07:13:46","guid":{"rendered":"https:\/\/www.fs1inc.com\/blog\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\/"},"modified":"2025-12-11T02:13:46","modified_gmt":"2025-12-11T07:13:46","slug":"dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance","status":"publish","type":"post","link":"https:\/\/www.fs1inc.com\/blog\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\/","title":{"rendered":"P2891 Code Symptoms, Causes, Diagnosis and Repair Guide Step-by-Step"},"content":{"rendered":"<div class=\"container\">\n<section class=\"hero\">\n<div class=\"code-badge\">P2891<\/div>\n<h1>P2891 Code Symptoms, Causes, Diagnosis and Repair Guide Step-by-Step<\/h1>\n<p class=\"hero-subtitle\">\n<\/section>\n<div class=\"quick-summary\">\n<h2>Quick Summary<\/h2>\n<ul>\n<li>P2891 signals a Cylinder 1 ion\u2011current\u2011sense circuit that is out of range. <\/li>\n<li>Typical driver alerts: check\u2011engine light, rough idle, misfire on cylinder 1, loss of power, possible limp\u2011mode. <\/li>\n<li>Primary culprits: ion\u2011sensor failure, wiring\/connectors, ECM internal fault, or corrupted software. <\/li>\n<li>Diagnosis starts with a live scan, wiring continuity check, and ion\u2011sensor voltage verification. <\/li>\n<li>Replacement of the ECM (or a re\u2011programmed VIN\u2011matched unit) is often the most reliable cure; Flagship One supplies fully programmed modules.<\/li>\n<\/ul>\n<\/div>\n<h3>Introduction <\/h3>\n<p>When the engine control module (ECM) detects abnormal ion\u2011current values from cylinder 1\u2019s combustion event, it stores the P2891 code. Drivers usually notice the check\u2011engine lamp illuminate, followed by a rough\u2011idle condition or a noticeable misfire on the first cylinder. Power delivery may dip, especially under load, and the ECM can command a limp\u2011mode to protect the engine. Because the fault originates in the ion\u2011current\u2011sense circuit, the issue is tied directly to the ECM\u2019s ability to read combustion events, not to a conventional sensor or fuel component. Early identification prevents prolonged drivability loss and avoids unnecessary component replacement.<\/p>\n<h2>Symptoms <\/h2>\n<ul>\n<li><strong>Check\u2011engine light (CEL) illuminated<\/strong> \u2013 the ECM logs P2891 and may trigger additional codes such as P0301 (cylinder 1 misfire). <\/li>\n<li><strong>Rough or uneven idle<\/strong> \u2013 engine speed wavers as the ECM reduces power to the affected cylinder. <\/li>\n<li><strong>Cylinder 1 misfire<\/strong> \u2013 a distinct \u201ctap\u201d or hesitation when accelerating, especially at low RPM. <\/li>\n<li><strong>Reduced acceleration or power loss<\/strong> \u2013 the ECM trims fuel and spark to protect the engine, resulting in sluggish response. <\/li>\n<li><strong>Limp\u2011mode activation<\/strong> \u2013 in severe cases the ECM limits RPM to prevent damage, causing the vehicle to stay in a low\u2011gear or low\u2011speed range. <\/li>\n<\/ul>\n<p>While a faulty spark plug, ignition coil, or fuel injector could produce similar misfire symptoms, the P2891 definition points to the ion\u2011current\u2011sense circuit. A diagnostic scan will confirm whether the ECM or its circuitry is at fault before any peripheral parts are replaced.<\/p>\n<h2>Why This Happens <\/h2>\n<h3>Ion\u2011Current\u2011Sense Sensor Failure <\/h3>\n<p>The ion sensor monitors the electrical conductivity of the combustion gases after ignition. Excessive or insufficient ion current indicates incomplete combustion, prompting the ECM to store P2891. Sensor degradation, contamination, or internal short circuits are common causes.<\/p>\n<h3>Wiring or Connector Problems <\/h3>\n<p>The ion\u2011current signal travels through a dedicated high\u2011frequency wire harness. Corrosion, frayed conductors, or loose connector pins can distort the signal, causing the ECM to read values outside its calibrated range.<\/p>\n<h3>ECM Internal Circuit Fault <\/h3>\n<p>The ECM houses the analog front\u2011end that amplifies and interprets ion\u2011current signals. Moisture ingress, solder joint cracks, or component fatigue can corrupt the measurement, leading to persistent P2891 even when the sensor and wiring are sound.<\/p>\n<h3>Software Calibration Issue <\/h3>\n<p>ECM firmware defines acceptable ion\u2011current thresholds for each cylinder. An outdated or corrupted calibration map may misinterpret normal signals as out\u2011of\u2011range, especially after a flash update or after the vehicle has undergone a major service.<\/p>\n<h3>External Influences <\/h3>\n<p>Extreme engine temperatures, excessive carbon buildup, or abnormal combustion pressure can temporarily raise ion\u2011current levels. If the ECM repeatedly encounters these spikes, it may log P2891 until the underlying condition is corrected.<\/p>\n<h2>Diagnostic and Repair Procedures <\/h2>\n<ol>\n<li><strong>Read Live Data<\/strong> \u2013 Connect a professional scan tool, select the ion\u2011current sensor channel for cylinder 1, and compare the real\u2011time voltage (typically 0.2\u20130.6 V) to manufacturer specifications.\n<\/li>\n<li><strong>Verify Sensor Resistance<\/strong> \u2013 With the ignition off, disconnect the ion sensor plug and measure resistance across the sensor leads. Values outside the 10\u201330 k\u03a9 range suggest a failed sensor.\n<\/li>\n<li><strong>Inspect Wiring Harness<\/strong> \u2013 Visually examine the sensor wire for abrasion, chafing, or corrosion. Perform a continuity test (\u2265 0.9 \u03a9) and check for short\u2011to\u2011ground or short\u2011to\u2011power conditions.\n<\/li>\n<li><strong>ECM Communication Test<\/strong> \u2013 Use the scan tool to ping the ECM and confirm that all control modules respond correctly. Communication errors may indicate a deeper ECM fault.\n<\/li>\n<li><strong>Software Version Check<\/strong> \u2013 Review the ECM firmware version. If it is older than the latest release, update the software using the manufacturer\u2019s re\u2011programming procedure.\n<\/li>\n<li><strong>Component Replacement<\/strong> \u2013\n<\/li>\n<\/ol>\n<p> &#8211; <strong>Sensor<\/strong>: Replace only after confirming wiring integrity and ECM health. <\/p>\n<p> &#8211; <strong>Wiring\/Connector<\/strong>: Repair or replace damaged sections, ensuring proper crimp and seal. <\/p>\n<p> &#8211; <strong>ECM<\/strong>: If the ion\u2011current front\u2011end fails or software updates do not clear the code, replace the ECM with a VIN\u2011matched, pre\u2011programmed unit. <\/p>\n<p><strong>Cost Estimates<\/strong> <\/p>\n<ul>\n<li>Ion sensor: $30\u2011$80 (parts) + $50\u2011$100 labor. <\/li>\n<li>Wiring repair: $20\u2011$60 parts + $80\u2011$120 labor. <\/li>\n<li>ECM re\u2011programming: $100\u2011$150 labor; full replacement: $600\u2011$900 plus $200\u2011$300 labor. <\/li>\n<\/ul>\n<h2>When Replacement Makes More Sense Than Repair <\/h2>\n<div class=\"flagship-logo-section\">\n<a href=\"https:\/\/www.fs1inc.com\/\" rel=\"noopener noreferrer\" target=\"_blank\"><br \/>\n<img decoding=\"async\" alt=\"Flagship One\" class=\"flagship-logo\" src=\"https:\/\/www.fs1inc.com\/blog\/wp-content\/uploads\/2025\/12\/fs1inc_logo2-scaled.jpg\"\/><br \/>\n<\/a>\n<\/div>\n<p>If the ECM\u2019s ion\u2011current front\u2011end shows signs of internal damage\u2014such as recurring P2891 after sensor and wiring replacement, or intermittent communication failures\u2014repair attempts become temporary fixes. The module\u2019s analog circuitry is highly integrated; once compromised, it often leads to additional fault codes and reduced reliability. <\/p>\n<p>Modern control modules are complex and integrated with security and immobilizer systems. That\u2019s why choosing a replacement isn\u2019t only about the hardware\u2014it&#8217;s about correct programming and compatibility. Flagship One specializes in VIN\u2011matched control modules, providing a plug\u2011and\u2011drive solution backed by warranty. Replacement units vary depending on production date and software version, so the correct module is matched by VIN before programming, ensuring seamless integration with your vehicle\u2019s network.<\/p>\n<h2>Preventive Maintenance <\/h2>\n<ul>\n<li><strong>Keep the ignition system clean<\/strong> \u2013 carbon deposits on spark plugs and combustion chambers can alter ion\u2011current readings. Replace spark plugs per the manufacturer\u2019s interval. <\/li>\n<li><strong>Protect wiring<\/strong> \u2013 route the ion\u2011sensor harness away from moving parts and heat sources; use protective sleeves in high\u2011temperature zones. <\/li>\n<li><strong>Regular ECM health checks<\/strong> \u2013 during scheduled service, have a technician run a live data scan to verify ion\u2011current sensor outputs and ECM communication integrity. <\/li>\n<li><strong>Software updates<\/strong> \u2013 stay current with OEM firmware releases; many updates refine ion\u2011current thresholds and improve fault tolerance. <\/li>\n<li><strong>Avoid excessive fuel additives<\/strong> \u2013 high\u2011detonation fuels can cause abnormal combustion pressures that temporarily raise ion currents.<\/li>\n<\/ul>\n<div class=\"info-section\">\n<p><strong>Service Recommendation:<\/strong> Most issues related to this fault are diagnosed and corrected through inspection, wiring repair, and calibration rather than module replacement. For modules not typically replaced through aftermarket suppliers, diagnosis and repair should be performed by a certified automotive technician with access to factory service information and tooling.<\/p>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Misfire on your vehicle? P2891 indicates Cylinder 1 ion current sense circuit out of range\u2014cuts power. Scan, test ion sensor, re\u2011program or replace module.<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"elementor_header_footer","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[4],"tags":[],"class_list":["post-518873","post","type-post","status-publish","format-standard","hentry","category-auto-news"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.7 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>P2891 Code Symptoms, Causes, Diagnosis and Repair Guide Step-by-Step - 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\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"P2891 Code Symptoms, Causes, Diagnosis and Repair Guide Step-by-Step - Flagship One Blog\" \/>\n<meta property=\"og:description\" content=\"Misfire on your vehicle? P2891 indicates Cylinder 1 ion current sense circuit out of range\u2014cuts power. Scan, test ion sensor, re\u2011program or replace module.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.fs1inc.com\/blog\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\/\" \/>\n<meta property=\"og:site_name\" content=\"Flagship One Blog\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/flagshipone\" \/>\n<meta property=\"article:author\" content=\"https:\/\/www.facebook.com\/flagshipone\/\" \/>\n<meta property=\"article:published_time\" content=\"2025-12-11T07:13:46+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/www.fs1inc.com\/blog\/wp-content\/uploads\/2025\/12\/fs1inc_logo2-scaled.jpg\" \/>\n<meta name=\"author\" content=\"FlagshipOne\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:creator\" content=\"@theflagshipone\" \/>\n<meta name=\"twitter:site\" content=\"@theflagshipone\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"FlagshipOne\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"5 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\\\/\"},\"author\":{\"name\":\"FlagshipOne\",\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/#\\\/schema\\\/person\\\/a3cf463514bd03eb7656953ef8f75700\"},\"headline\":\"P2891 Code Symptoms, Causes, Diagnosis and Repair Guide Step-by-Step\",\"datePublished\":\"2025-12-11T07:13:46+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\\\/\"},\"wordCount\":1049,\"commentCount\":0,\"publisher\":{\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/#organization\"},\"image\":{\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/wp-content\\\/uploads\\\/2025\\\/12\\\/fs1inc_logo2-scaled.jpg\",\"articleSection\":[\"Auto News\"],\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\\\/#respond\"]}]},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\\\/\",\"url\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\\\/\",\"name\":\"P2891 Code Symptoms, Causes, Diagnosis and Repair Guide Step-by-Step - Flagship One Blog\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\\\/#primaryimage\"},\"image\":{\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/wp-content\\\/uploads\\\/2025\\\/12\\\/fs1inc_logo2-scaled.jpg\",\"datePublished\":\"2025-12-11T07:13:46+00:00\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\\\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\\\/\"]}]},{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\\\/#primaryimage\",\"url\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/wp-content\\\/uploads\\\/2025\\\/12\\\/fs1inc_logo2-scaled.jpg\",\"contentUrl\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/wp-content\\\/uploads\\\/2025\\\/12\\\/fs1inc_logo2-scaled.jpg\",\"width\":2560,\"height\":617},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"P2891 Code Symptoms, Causes, Diagnosis and Repair Guide Step-by-Step\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/#website\",\"url\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/\",\"name\":\"Flagship One Blog\",\"description\":\"Flagship One Inc. OEM Engine Computers  Control Modules\",\"publisher\":{\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/#organization\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"},{\"@type\":\"Organization\",\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/#organization\",\"name\":\"Flagship One, Inc.\",\"url\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/#\\\/schema\\\/logo\\\/image\\\/\",\"url\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/wp-content\\\/uploads\\\/2019\\\/06\\\/web-lg-fs1-logo.png\",\"contentUrl\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/wp-content\\\/uploads\\\/2019\\\/06\\\/web-lg-fs1-logo.png\",\"width\":1341,\"height\":1098,\"caption\":\"Flagship One, Inc.\"},\"image\":{\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/#\\\/schema\\\/logo\\\/image\\\/\"},\"sameAs\":[\"https:\\\/\\\/www.facebook.com\\\/flagshipone\",\"https:\\\/\\\/x.com\\\/theflagshipone\",\"https:\\\/\\\/www.instagram.com\\\/flagship_one\",\"https:\\\/\\\/www.youtube.com\\\/channel\\\/UC0oyKphffBM2qkJ-gKPmMXw\"]},{\"@type\":\"Person\",\"@id\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/#\\\/schema\\\/person\\\/a3cf463514bd03eb7656953ef8f75700\",\"name\":\"FlagshipOne\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/351b81e51993825aea73280c48061a7205fdd2189730ebbdee5d63894c5cebb4?s=96&d=mm&r=g\",\"url\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/351b81e51993825aea73280c48061a7205fdd2189730ebbdee5d63894c5cebb4?s=96&d=mm&r=g\",\"contentUrl\":\"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/351b81e51993825aea73280c48061a7205fdd2189730ebbdee5d63894c5cebb4?s=96&d=mm&r=g\",\"caption\":\"FlagshipOne\"},\"description\":\"The world's top supplier of programmed OEM (Original Equipment Manufacturer) Powertrain Control Modules (PCM), Engine Control Modules (ECM), Injection Control Modules (IDM), Body Control Modules (BCM), Transmission Control Modules (TCM), Engine Control Units and all other car control units. With over a decade in the business, we are the most reliable source when it comes to programming services for replacement engine control modules.\",\"sameAs\":[\"https:\\\/\\\/www.fs1inc.com\\\/\",\"https:\\\/\\\/www.facebook.com\\\/flagshipone\\\/\",\"https:\\\/\\\/www.instagram.com\\\/flagship_one\\\/\",\"https:\\\/\\\/www.linkedin.com\\\/company\\\/fs1inc\"],\"url\":\"https:\\\/\\\/www.fs1inc.com\\\/blog\\\/author\\\/flagship1inc\\\/\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"P2891 Code Symptoms, Causes, Diagnosis and Repair Guide Step-by-Step - Flagship One Blog","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.fs1inc.com\/blog\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\/","og_locale":"en_US","og_type":"article","og_title":"P2891 Code Symptoms, Causes, Diagnosis and Repair Guide Step-by-Step - Flagship One Blog","og_description":"Misfire on your vehicle? P2891 indicates Cylinder 1 ion current sense circuit out of range\u2014cuts power. Scan, test ion sensor, re\u2011program or replace module.","og_url":"https:\/\/www.fs1inc.com\/blog\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\/","og_site_name":"Flagship One Blog","article_publisher":"https:\/\/www.facebook.com\/flagshipone","article_author":"https:\/\/www.facebook.com\/flagshipone\/","article_published_time":"2025-12-11T07:13:46+00:00","og_image":[{"url":"https:\/\/www.fs1inc.com\/blog\/wp-content\/uploads\/2025\/12\/fs1inc_logo2-scaled.jpg","type":"","width":"","height":""}],"author":"FlagshipOne","twitter_card":"summary_large_image","twitter_creator":"@theflagshipone","twitter_site":"@theflagshipone","twitter_misc":{"Written by":"FlagshipOne","Est. reading time":"5 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/www.fs1inc.com\/blog\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\/#article","isPartOf":{"@id":"https:\/\/www.fs1inc.com\/blog\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\/"},"author":{"name":"FlagshipOne","@id":"https:\/\/www.fs1inc.com\/blog\/#\/schema\/person\/a3cf463514bd03eb7656953ef8f75700"},"headline":"P2891 Code Symptoms, Causes, Diagnosis and Repair Guide Step-by-Step","datePublished":"2025-12-11T07:13:46+00:00","mainEntityOfPage":{"@id":"https:\/\/www.fs1inc.com\/blog\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\/"},"wordCount":1049,"commentCount":0,"publisher":{"@id":"https:\/\/www.fs1inc.com\/blog\/#organization"},"image":{"@id":"https:\/\/www.fs1inc.com\/blog\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\/#primaryimage"},"thumbnailUrl":"https:\/\/www.fs1inc.com\/blog\/wp-content\/uploads\/2025\/12\/fs1inc_logo2-scaled.jpg","articleSection":["Auto News"],"inLanguage":"en-US","potentialAction":[{"@type":"CommentAction","name":"Comment","target":["https:\/\/www.fs1inc.com\/blog\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\/#respond"]}]},{"@type":"WebPage","@id":"https:\/\/www.fs1inc.com\/blog\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\/","url":"https:\/\/www.fs1inc.com\/blog\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\/","name":"P2891 Code Symptoms, Causes, Diagnosis and Repair Guide Step-by-Step - Flagship One Blog","isPartOf":{"@id":"https:\/\/www.fs1inc.com\/blog\/#website"},"primaryImageOfPage":{"@id":"https:\/\/www.fs1inc.com\/blog\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\/#primaryimage"},"image":{"@id":"https:\/\/www.fs1inc.com\/blog\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\/#primaryimage"},"thumbnailUrl":"https:\/\/www.fs1inc.com\/blog\/wp-content\/uploads\/2025\/12\/fs1inc_logo2-scaled.jpg","datePublished":"2025-12-11T07:13:46+00:00","breadcrumb":{"@id":"https:\/\/www.fs1inc.com\/blog\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.fs1inc.com\/blog\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\/"]}]},{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.fs1inc.com\/blog\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\/#primaryimage","url":"https:\/\/www.fs1inc.com\/blog\/wp-content\/uploads\/2025\/12\/fs1inc_logo2-scaled.jpg","contentUrl":"https:\/\/www.fs1inc.com\/blog\/wp-content\/uploads\/2025\/12\/fs1inc_logo2-scaled.jpg","width":2560,"height":617},{"@type":"BreadcrumbList","@id":"https:\/\/www.fs1inc.com\/blog\/dtc-p2891-cylinder-1-ion-current-sense-circuit-rangeperformance\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/www.fs1inc.com\/blog\/"},{"@type":"ListItem","position":2,"name":"P2891 Code Symptoms, Causes, Diagnosis and Repair Guide Step-by-Step"}]},{"@type":"WebSite","@id":"https:\/\/www.fs1inc.com\/blog\/#website","url":"https:\/\/www.fs1inc.com\/blog\/","name":"Flagship One Blog","description":"Flagship One Inc. OEM Engine Computers  Control Modules","publisher":{"@id":"https:\/\/www.fs1inc.com\/blog\/#organization"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/www.fs1inc.com\/blog\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"},{"@type":"Organization","@id":"https:\/\/www.fs1inc.com\/blog\/#organization","name":"Flagship One, Inc.","url":"https:\/\/www.fs1inc.com\/blog\/","logo":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.fs1inc.com\/blog\/#\/schema\/logo\/image\/","url":"https:\/\/www.fs1inc.com\/blog\/wp-content\/uploads\/2019\/06\/web-lg-fs1-logo.png","contentUrl":"https:\/\/www.fs1inc.com\/blog\/wp-content\/uploads\/2019\/06\/web-lg-fs1-logo.png","width":1341,"height":1098,"caption":"Flagship One, Inc."},"image":{"@id":"https:\/\/www.fs1inc.com\/blog\/#\/schema\/logo\/image\/"},"sameAs":["https:\/\/www.facebook.com\/flagshipone","https:\/\/x.com\/theflagshipone","https:\/\/www.instagram.com\/flagship_one","https:\/\/www.youtube.com\/channel\/UC0oyKphffBM2qkJ-gKPmMXw"]},{"@type":"Person","@id":"https:\/\/www.fs1inc.com\/blog\/#\/schema\/person\/a3cf463514bd03eb7656953ef8f75700","name":"FlagshipOne","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/secure.gravatar.com\/avatar\/351b81e51993825aea73280c48061a7205fdd2189730ebbdee5d63894c5cebb4?s=96&d=mm&r=g","url":"https:\/\/secure.gravatar.com\/avatar\/351b81e51993825aea73280c48061a7205fdd2189730ebbdee5d63894c5cebb4?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/351b81e51993825aea73280c48061a7205fdd2189730ebbdee5d63894c5cebb4?s=96&d=mm&r=g","caption":"FlagshipOne"},"description":"The world's top supplier of programmed OEM (Original Equipment Manufacturer) Powertrain Control Modules (PCM), Engine Control Modules (ECM), Injection Control Modules (IDM), Body Control Modules (BCM), Transmission Control Modules (TCM), Engine Control Units and all other car control units. With over a decade in the business, we are the most reliable source when it comes to programming services for replacement engine control modules.","sameAs":["https:\/\/www.fs1inc.com\/","https:\/\/www.facebook.com\/flagshipone\/","https:\/\/www.instagram.com\/flagship_one\/","https:\/\/www.linkedin.com\/company\/fs1inc"],"url":"https:\/\/www.fs1inc.com\/blog\/author\/flagship1inc\/"}]}},"_links":{"self":[{"href":"https:\/\/www.fs1inc.com\/blog\/wp-json\/wp\/v2\/posts\/518873","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.fs1inc.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.fs1inc.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.fs1inc.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.fs1inc.com\/blog\/wp-json\/wp\/v2\/comments?post=518873"}],"version-history":[{"count":0,"href":"https:\/\/www.fs1inc.com\/blog\/wp-json\/wp\/v2\/posts\/518873\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.fs1inc.com\/blog\/wp-json\/wp\/v2\/media?parent=518873"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.fs1inc.com\/blog\/wp-json\/wp\/v2\/categories?post=518873"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.fs1inc.com\/blog\/wp-json\/wp\/v2\/tags?post=518873"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}