Wednesday, 26 May 2021

BMW M40 Engine - how to check timing, where the marks are located

This must be one of the hardest bits of info to find in the whole world of BMW, but there is a great post on BMW Werks on how to do it [https://www.bimmerwerkz.com/threads/m40-motor-timing-info.59059/].

QUICK TIMING CHECK GUIDE:

** Only if crank pulley has NOT been separated from crankshaft! **

1. Remove the distributor / timing cover at the front of the engine.

2. Check the timing mark on the crank pulley. This is an arrow cast into the block which should line up with the sprocket tooth to the right of the gap in the teeth, as in pic below.


3. Check the timing mark on the camshaft pulley. This is a notch/line mark in the pulley and should line up with the right-angle notch in the cylinder head, as in pic below. If this looks good, your timing is fine.


Thanks again to xdrian on BMW Works for making these pics and sharing this secret!

Monday, 24 May 2021

E30 318i: New Bosch spark plugs + correct coil fitted

With the car still misfiring a bit, I turned my attention to the plugs and HT leads. All appear fine. The coil works because there is a spark. I inspected the plugs, a set of NGK R that don't look particularly ancient, expecting one or more to be wet with unburnt fuel from a combination of misfiring and running an over-rich mixture from tweaking the air-flow meter [AFM]. I noticed that the plugs were in fact all dry and totally black with soot at the tips from over-fuelling, but their condition seemed fine. This matched the points in the distributor-cap, which were also blackened.

The spark plugs were working, but they didn't seem to fully igniting the mixture and performing weakly, so I turned my attention back to the coil. A previous owner had fitted a universal 'Sports coil' and judging by the shiny casing it doesn't look too old, so I couldn't see how it could be at fault. Thats when I noticed the terminal connecting it to the HT lead. It's about 10mm wide and has a metal inner lining. There is a screw at the bottom holding it in. This is obviously designed for a different type of HT lead than fitted to BMW, as the lead has a rubber plug where

it contacts the copper casing of the terminal in the coil. The metal terminal in the HT lead is designed to fit over a stud inside the coil-terminal, which is what I've always seen before, not just in BMW. This means the only contact being made by the main HT lead was its very tip touching the screw at the bottom of the coil-terminal.

I swiftly ordered a used OEM Bosch coil unit from eBay for £15. A 'Sports coil' type with the correct end was about £35, but I figured it was best to go original, at least for the time being while I iron out the M40 engine's running problems. While I was at it, I bought some OEM Bosch spark plugs for £13, which is cheap and I thought I may as well rule out plug condition as a factor with not knowing how long the incorrect coil has been fitted to the E30. 


Sunday, 25 April 2021

Causes of flat batteries on BMWs explained - Great guide!!

If you own an older BMW, no doubt you will have experienced your battery suddenly starting to go dead for no apparent reason. All modern BMWs have a ‘shut-down’ procedure after the ignition is turned off, things can be heard whirring and humming even after you’ve locked the car and this is the most common cause of your battery going dead over night with no warning, but there are others too...

Below is a great guide from Vlad at MCA Blog explaining the reasons BMW batteries go flat over night and where to check. It also details that bane of the BMW battery's life, the 'IBS' or Intelligent Battery Sensor fitted from the '90s on. 

https://mca.electricmura.ro/en/blog-bmw-what-causes-dead-battery/



  • Plugged in external devices
  • Plugged in OBD-II scanner
  • BMW Intelligent Battery Sensor
  • The infamous ”hedgehog” (from the climate control panel)
  • One of the electronics on your car drains too much power or does not go into sleep mode
  • Faulty alternator
  • Old battery

Monday, 12 April 2021

E46 318i Touring: Back on the road with new battery!

Despite paying road-tax and insurance on the E46 Touring it's been laid up for 6 months and with an improvement in the weather it's high time I put it back on the road. All it really needed was some air in the tyres and the brakes beating up. The battery was totally dead, however. The previous owner had put an AGM [automated glass-mat] battery design for vehicles with Start/Stop technology on it, which was great but clearly the 19 year old alternator and charging setup on the E46 was not up to the job of charging it properly. Ah well, it has lasted for over twelve months... 

I've always sworn by Bosch batteries, but the £100+ price tag these days, yes even with a Euro Car Parts discount code, is a bit too expensive for this car. ECP, as well as the parts dept. at work can offer a budget Lion battery for a little over £50, but I have been warned by everyone willing to give their fifty pence that these don't last five minutes and I should avoid like the plague. Ultra-budget batteries can be found on eBay for as little as £27, but who knows anything about their quality.

At this point I have to hand it to the parts dept. at work here, who loaded me up a Yuasa 3110 series battery [760Ah] for just £60 all in! Yuasa get a good write up, in fact I am told they beat Bosch in tests and are currently one of the best on the market. ECP could offer me a Yuasa for £67, but it was a tiny little square battery and this just goes to show how useful working or knowing someone in the motor-trade can be...



Thursday, 1 April 2021

F10 530d: Water in Battery well / Bootwell / Trunkwell - where is it leaking?

I lifted the boot/trunk floor to jump-start a friends car and noticed that my battery well / spare-wheel well is full of dirty water.... oh dear. I’ve got a leak... but where? Boot seal? Bottom of the rear windscreen? There was a second aerial / antenna fitted in the roof that I removed, so figured it might be leaking through there and running down the C-pillar into the boot, but no water marks in the headlining or signs of ingress... Think I will have a proper look this weekend and try get to the bottom of it!



Friday, 19 March 2021

BMW MOST Bus - Troubleshooting Guide [Vlad on MCA]

 Great guide to the BMW MOST Bus (Media Oriented Systems Transport), used in all BMWs with fibre-optic connectivity. It covers what it is and what it does, as well as troubleshooting a lot of associated problems with these complex systems. It is from Vlad at MCA.org and can be found here: 

https://mca.electricmura.ro/en/blog-bmw-most-troubleshoot/



Sunday, 14 March 2021

F10 530d: N57 EGR / Cooler related fault-code scan results

 Been getting the 'Drivetrain' malfunction message on my F10 530d iDrive and figured it likely to be EGR (exhaust-gas-recirculator) related, so plugged in a Snap-On Modis scanner and these are the codes I got, which are what I suspected to be honest. The EGR and EGR-cooler are known to pack in on the N57 series of engine, the latter of which can leak coolant into the inlet causing a bit of smoke on startup. 


28E200 - Exhaust Gas Temperature sensor before Cat, open circuit

255C00 - EGR Controller, Position Control, Valve open too far

190900 - EGR Mass Air Flow, measured plausibility calculated too high

240400 - EGR Control, control deviation air mass too low

272F09 - EGR, mechanically faulty close to open position

272E00 - EGR, mechanically faulty close to closed position

So, I have the classic two codes of the EGR failing close to open and closed position, which denotes a stuck EGR valve, which is quite common on all diesel engines, along with the EGR mass-air codes where values are higher and lower than they should be, which clearly ties in to the valve sticking in the open and closed position. Faults for the EGR control-module show that it is struggling to position the EGR correctly and this all points to one stuck EGR valve.

I also notice that I am getting a bit of smoke on startup sometimes which I have never noticed before. This also points to a faulty EGR-valve, or rather the cooler itself. The EGR-cooler is fed with coolant to reduce the operating temperature of the EGR-valve itself and these are known to have problems with leaking after time. They crack inside after prolonged use and start to leak coolant into the EGR and thereafter the air-intake, which causes a bit of white smoke on startup, which I have been experiencing the last few weeks and so it looks like this is the culprit and I will be replacing the EGR / cooler unit at some point I would imagine... watch this space.