All E30s, if unmodified, should have a basic tool set located inside the trunk: All tools were made by Heyco and stamped with the BMW logo. The kit included: 17/19mm wrench 12/13mm wrench 8/10mm wrench Pliers Allen key Screwdriver with a reversible blade (Phillips and flathead) Spark plug tool Plastic manual window crank (in...
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There are two main automotive fuel standards: one commonly referenced in North America (SAE) and the other in Europe (DIN). While these standards overlap in many aspects, they use very different naming conventions. Fuel hoses are typically categorized by pressure (low or high), permeation levels (low or high), and whether they are designed for...
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AFM to Airbox Gasket E30: Throttle body to Intake Manifold Gasket E30: Valve cover gasket E30:    
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Per the BMW E30 Factory Manual:   Per Bentley manual: To set between 0.20mm and 0.60mm:   Failure Methods: It is commonly stated online that E30 TPS failures are caused by oil saturation. Crankcase oil can migrate down the throttle body shaft bearings and into the TPS, leading some to recommend drilling a hole...
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If you’re in the market for a fog relay—particularly the now no longer available (NLA) part number 61311374631—here’s a crucial piece of information you should know before buying any replacement. The stock relay for this part comes with a diode, while most available replacements do not. This seemingly minor difference can cause some unexpected...
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This factory-style modification allows you to toggle the auxiliary fan to high speed when the AC is on, improving AC performance at idle. The E30 comes with a fog lamp switch, which in some markets is a double switch. By using the alternate switch (part number 61311380312) and adding two connectors to the existing...
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Here are some nuances to understand when picking E30 M20 accessory belts. First reference this to understand how some belt manufacturers describe the same length of belt in different ways: Understanding V-belt lengths Li vs La (inner length and outer length) Alternator and Waterpump belt The factory belt size is 9.5X965 – PN 11511711091...
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Pins and Sockets for most major connections (Eg. Diagnostic Connector, radiator temp switch, coolant level, etc) Pin Size BMW Part Number Part Type Wire Size (mm²) Wire Gauge (AWG) ITT Cannon Part Number TE Connectivity Part Number Description 2.5 mm 61131376191 Male 0.5–1.5 mm² 14–20 AWG APK-PB25A10-002 929963-1 Male terminal for 0.5–1.5 mm² wire 2.5 mm 61131376193 Male 1.0–2.5 mm²...
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One major quality-of-life improvement when performing a valve adjustment on an E30 is the ability to use the starter instead of a wrench and socket on the crankshaft to rotate each cam lobe away from the rocker for adjustment. Luckily, the diagnostic port on an E30 can trigger the starter by simply bridging pins...
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This article serves to provide nuanced detail for those looking to refresh their OEM setup (Denso with early style dryer in particular); one of the biggest roadblocks is that the OEM parts catalogue (ETK) is often wrong. Also, reference to this article for how to recharge the AC system: How to recharge the AC...
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