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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When changing the AC evaporator on a BMW E30, there’s definitely a right and a wrong way to do it. The glovebox is attached to the car by a brass-colored piano bracket. If you remove the black screws, you’re going to spend a lot of time realigning the glovebox when reinstalling. Instead, if you...
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There is only one correct way to test an E30 AFM, and that’s by using an oscilloscope. The most common mode of failure is the wearing of the carbon strip within the AFM. In simple terms, the AFM is one big variable resistor. It takes a +5V supply, and the carbon strip provides variable...
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If you decide to paint your wheels instead of powdercoating (which you should): Is powdercoating bad for rims? Yes, and illegal in Germany. So is using heat to bend them back. There is an nth amount of silvers to choose from, and there is no real right or wrong, but everyone needs somewhere to...
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Counter to popular narrative on E30 forums (based on self perpetuating hearsay), there are variant code differences between manual and auto E30 ECU’s and M1.3 didn’t always post date M1.1 ECU’s. The bad news is that no tuner has a fully disassembled dump of the ECU source code. Most just take the post compiled...
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