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BMW 525i

Make: BMW
Model: 525i (E28)
Year: 1985
Owned: 1992-1995

I purchased this BMW from an independent BMW specialist near Cranwell in Lincolnshire. It was in fantastic condition, having been previously owned by a company director. I couldn't find anything to fault it!!
However, after a few days it backfired a couple of times when starting it. I took it back and the guys at Cranwell found a split in the induction hose which they sorted with no problems at all.

I serviced the car every 6000 miles, always giving it an engine flush and other than routine maintenance and a couple of viscous fan couplings, nothing major went wrong for the next couple of years... but that annoying backfire was still there on the odd occasion.

Then it happened... I parked up in Tesco's, did my shopping, came out and tried to start her and .. BANG - a monster backfire... eeek.
I tried again and she started but as soon as I put my foot down, she'd stall.. I couldn't drive her home, so a quick call to my brother, Steve, and he towed me home which luckily was only around the corner.
Once home, Steve and I set about seeing what had gone wrong. It didn't take us long to find the problem... The entire bottom of the airflow sensor unit had been blown away from the main body and there was a gapping hole !
Now, at the time an airflow sensor was about £400 and I was a young bachelor who was still struggling to pay a mortgage on his first house and I wasn't going to fork out £400 on a part for a car !
So my alternatives were to find one in a breakers yard or fix it.
I thought I'd have a go at fixing it first... The unit was made up of the main casting and the base plate which were riveted together and sealed with what looked like silicon sealant (the old sealant was discoloured in places and looked like it had been leaking - could I have found my intermittent backfire ??)
I cut off the studs that formed the old rivets and drilled blind holes instead, which I then tapped out. I straightened the base plate, applied some silicon sealant around it's edge and then screwed it on to the main body.... would it work ??
After everything was reassembled, I gingerly turned her over and .... yeeee harrr, she burst into life AND I never had another backfire :o)... Sorted

It was a sad day when I decided to sell her but one of my friends popped around to see me and said.. "My boss is selling his BMW635csi.. you interested ??".. say no more..

BMW 635csi

Make: BMW
Model: 635csi (E24)
Year: 1985
Owned: 1995-1999

How could I say no ?... it was lovely. It had been looked after with no expense spared and came with a good service history including receipts going back years. Looking back, I think I was blinded by it's beauty! It wasn't in as good condition as the 525i but it was a 635csi and I was drooling. That said, it did look good considering that it had 110,000 miles on it and had been looked after. It had a blue leather interior (of which only the drivers seat was starting to show wear), aircon, cruise, nice audio unit, trip computer etc.... and it was a 635csi... drool... I think you're getting the picture.

Again, I decide to service this car myself.. I love these BMW straight six engines.
I wasn't quite so lucky with this car, other than service items, in the four years of ownership, she had:

OK, we'll start with the brake discs:

I'd recently fitted nice new 5-spoke alloy wheels to replace the original metric ones. I'd done this for two reasons... the old ones were a nightmare to clean and the price of the metric tyres was a tad expensive. I worked out that I could buy a complete set of new wheels fitted with imperial tyres for about the same amount of money as a set of metric tyres ! And of cause, from then on I'd be buying imperial tyres so my cost of motoring should decrease....
Anyway, I digress... back to the brake discs, the old ones were getting a tad thin and seeing as I'd got nice 5-spoke wheels fitted, I opted for some cross-drilled sports discs. They were a well-known make and not cheap. I was very careful fitting them, cleaned the hubs and used a run-out guage etc but within a few weeks was getting judder when braking. I complained and eventually got them exchanged (but not without all the usual arguments about not fitting them correctly etc.). I fitted the new discs and again I started getting problems... at this stage I gave up, bought some aftermarket 'normal' discs, fitted them and had no problems whatsoever!

Reverse gear selector fork:

I'd already had a bad day. I'd been asked by the boss to visit a Lady in a village in the middle of nowhere to look at her home computer. I admit, she'd been messed about a bit, so I wasn't expecting tea and biscuits but she could have been a little more polite about it... after all, I was only there to help her :o(
Basically, she'd been visited by a few engineers and still had a problem, so had complained to 'Customer Relations', who'd agreed to exchange the computer for a different, upgraded spec machine.. this she accepted (I would have too.. it was well good - much better that the old one). Anyway my mission, should I accept, was to visit this Lady, uninstall her old PC and install the new one. Nice jolly, I thought, I'll do that!... Big mistake.
I drove out in the the wilds of Rutland, found her house and parked up.. in the mud (now I've lived in the country for years, so a little mud, I don't mind, but there's mud and there's mud - I'd found the deep mud... arrghhh). Her place was a was a nice old house made from sandstone etc, I knocked on the door and was greeted by a nice elderly Lady. While she looked me up and down, I introduced myself. Her eyes had stopped at my feet.
'Err.. I'll take my shoes off' I said quickly as I stepped in to her house. Now, nice as old village houses are, they have cold stone floors and my feet were already feeling it and I hadn't even started the job yet.
I was shown into the 'Study' and there, built in to a purpose made cabinet was her old PC and a load of big boxes containing her new PC. It all looked very nice, but how the hell was I going to get all the wires through that cabinet neatly... It started to dawn on me that this wasn't going to be a jolly.....
The Lady said "You OK - know what you're doing? Good, well I'm off, see you in an hour... If you need anything, just shout, the husband's around somewhere." and then she was gone. I was standing there, surrounded by new and old computer equipment and I was standing on a stone floor... crumbs.. my feet were cold.
For the next hour I busied myself, stripping out the old PC and installing the new one. I did nearly have kittens at one point when I thought that the new PC wouldn't physically fit into the custom built cabinet.. but it did fit .. phew. I carefully routed cables, skinned most of my knuckles and said a few choice words under my breath.
Eventually I was finished and I was pleased with myself... there would be no complaints about me.
Just at this point, the nice Lady reappeared, looked at me and said "Well, I'm not happy with that !"
"Err.. Not happy with what ?" I enquired.
"That computer, it's black, it doesn't go with the decor !"
Arrrgghhh ... yes, I admit that the new computer was black (and a funky black at that) and that the old one was a rather boring cream colour. Do people buy computers to go with their decor -- first I'd heard of it ! (in those days anyway).
I went on to explain that she'd got a really good deal, this new PC was far superior to her old one. I really did not want to have to come back again to install another PC of the 'correct' colour.
After a good 30 minutes of discussion and me explaining the virtues of the 'Black Beast', I'd won, she'd accepted..... Yesss.
All I had to do now, was lug the old PC and bits 'n' pieces over the road, stick them it the boot and I'd be off. Now, the BM has a reasonable sized boot, but with all my gear in there, it was going to be a bit of a squeeze. I ended up rearranging everything to get it all to fit.
At last, I was ready to leave and get back to civilization. I started up the 635, slipped her into reverse and ... TWANG. I didn't like the sound of that! It wouldn't have been so bad, if it hadn't been stuck in reverse. If it had been a case of not being able to get into reverse, I could have driven home. But, oh no, it was definitely stuck in reverse and I didn't fancy reversing all the way home!
I could have cried. What should I do? Just as well I joined the RAC then. I called them and they said that they'd be there within the hour.
So, I now had up to an hour to kill, I still had cold feet, I could only keep the engine running to keep me warm if I kept my foot on the clutch and I didn't fancy that. I suppose that I could have gone back for a chat with the Lady with the black computer but no... I'd spied something much more inviting ... a pub. I quickly scrawled a note to the RAC man, saying that I'd be in the pub and that if he wanted one, I'd buy him a pint and stuck it in the windscreen.
It looked a nice pub. I opened the door, walked in and WHACK! That's the problem with old village pubs, they've got low ceilings with bloody great wooden rafters. Now I had cold feet, a knackered car and a throbbing head.
The good things about the pub were that it sold beer, had a lovely real fire and the people were friendly, I even managed to get a sandwich. Having said that, it was a pub sandwich... you know what I mean, you think you're going to get a couple of bits of bread with a lump of something chucked in the middle, but no, you get a loaf of bread, sliced down the middle, half a cow stuck in there, a load of salad and masses of chips. Normally, I'd be well pleased, but just as I'd taken my first bite, who should walk in but the RAC man. Oh no.. perhaps I can persuade him to have a pint with me while I finished my food.
"Sorry, got to get a move on, got other customers to get to..."
So, sarny in hand, I left the pub, saying goodbye to all the friendly people and I managed to miss all the rafters on the way ... bonus.
The RAC man took one look at my lovely BM and said "That looks a little low to get on the back of my wagon".
Oh, come on, is anything going to go right for me today?
Anyway, we managed to get it on his wagon with only a slight scrape of the front valance and then we were homeward bound.
Once home, I cracked open a few beers, forgot about computers, cars and Ladies who buy computers to match their decor.
The following day I started the task of looking into getting my car fixed.
I put the car on the ramps, looked at the gearbox and decided that it'd be too heavy for me to remove safely.
Rang BMW: "Sorry, Sir, we don't fix them anymore, It'll be an exchange gearbox... cost about £1400.
Rang BMW Specialist: "Sorry Mate, we don't fix 'em, It'll be an exchange 'box .... cost about £700, I'd suggest you find yourself a gearbox specialist and see if they can repair it.
Rang a gearbox specialist: "Yep, no probs, we'll collect the car too... cost about £300 if you want the clutch changing at the same time"
"Fine.. Come and get it, oh and yes, stick a new clutch in it while you're at it, please"
Well that seemed pretty painless......
A week later... picked the car up and drove it home, hmm.. clutch feels a little juddery. "Oh yes, it will Sir, just let it bed in for a few thousand miles"... Oh no... I've heard that one before.
Luckily, I had a high mileage week but it was still juddery... back the car went for another 3 days.
On picking it up this time, it felt great, lovely and smooth... that was until I got back to Melton. I went to change gear and it felt like the gearstick was going to come off in my hand... no clutch judder though! I thought "Oh stuff it" (or words to that effect), "I'll pop down to ATS in Melton to see the lads (if you're ever in Melton, forget the rest, ATS is the best) and see if they'll let me just pop her on the ramps to see what's going on." This I did, and the selector mechanism was virtually hanging off. If you want a job doing properly, do it yourself and this is what I did.
I was a little worried that if they'd missed tightening the selector mech, what else may they have forgotten but, to be fair, I never had any further problems.

ABS light on:

It was a few days before the MOT was due... started her up and the ABS light stayed on... Sods law, if she'd just waited a few days for the MOT to pass, I'd of had some time to investigate but no it had to fail then didn't it. So, that evening, there I was scratching my head, thinking what could be the cause. The ABS sensors seemed the obvious place to start, but how to test them ?
I know, I thought, I'll dust off my scope, connect it to the sensor and spin the wheel to see if I get any output... logical as this may seem, this was a mistake. I didn't know what output to expect etc, so was working blind. I tested every wheel sensor and all had output of some kind... Rats, perhaps it's the ABS computer or a wiring problem.
Running out of ideas, I rang BMW and asked how much it would cost to have the ABS checked over. From what I remember, it was about £100 plus parts (which could have been anything from £80 for an ABS sensor to ?? for the computer (I didn't ask)). Seeing as the MOT was looming, I felt forced into having BMW check the car over and relinquishing me of £100+, so booked the car in for the next day.
After putting the phone down, I sat there thinking that there must be some way of sorting this myself... I wasn't doing to be beaten.. BMW weren't having my cash!!
So I thought about it.. how do these sensors work ? Well, all they are is a magnet with a winding around them. As the raised portion on the hub ring passes over the magnet, it induces a current and this is what is used to determine whether the wheel is turning and at what speed. Ahhh, I thought, all I need to do then is check the resistance of the windings. This I did and the reading of the front nearside sensor was different to all the others - result.
I removed the sensor from the car and checked the cable... half way along was a bulge. Now, BMW and the Haynes manual advise against repairing the sensors because of the small currents / voltages involved but I think as long as you do a good job, solder any connections and then seal the repair properly all should be OK.
I cut the cable, stripped the wires back and noticed that the copper wire was very tarnished / corroded, so I stripped it back further and further and further. Hmm, this was not looking good... looked like I was going to have to exchange all the wiring but the connector and sensor are moulded on. Luckily the wires near the ends of the cable were nice and clean. All I had to do now was find some cable the same... round, flexible, twin wire cable, so off I went down to the local electricians and, stuff me, he had some that looked and felt identical.... cost £1.50 / meter.
An hour later I'd soldered each individual wire together and sealed them with heat-shrink tubing, then sealed the complete cable with larger heat-shrink tubing. Fitted the sensor back on the car and tested it all OK - I was well happy with that.
But better was to come... I called the BMW dealer, with a smug smile on my face and cancelled the booking. What would have probably cost me £150-£180, actually cost me £1.50 and about 3 hours of my time... that's what I call satisfaction.

A fuel pressure regulator:

I started the car one morning and it was really rough with black smoke belching out the back. Now, I'm the first to admit that I'm not a fuel injection guru... I had a quick check around to see if there was anything obvious but, no, nothing that I could see. It so happened that on a recent visit to nearby Loughborough, I'd spied a company called Turbo Power Services who were fuel injection specialists. So a quick call to my friend Mike Howard who happens to own a car trailer and off we went to Loughborough. The guys at TPS diagnosed the problem as a defective fuel regulator which was replaced... job done.

Stalling and Starting problem:

What can I say, I could spend ages describing this problem and it's resolution but I'll try to be concise!
Every so often, the car would stall and refuse to start again... of course this normally happened in heavy traffic or at traffic lights... in fact, anywhere where it would cause maximum chaos.
I spent hours / days trying to track this problem down. I scoped all the engine sensors, checked all the electrical connections etc until one Sunday morning it failed on me, right there on the drive. Steve was around at the time, so we both set about finding out why it wouldn't start.... then it started .. bugger. We wasted all day, trying to get it to fail again, but no, it was not going to fail. Resigned to another wasted day, so we packed up, got showered / changed and decided to go out to a village pub for a few beers.
Got in the car... it wouldn't start... Arrrghh. Out we both jumped, metered and scoped every connector we could find and then we found it. The main power feed to the ECU was registering as 6v... should have been 12v. We rigged up a 12v feed and she burst into life.... then we went to the pub.
Over the next 6 months or so, I slowly worked my way back through the wiring (Sytners of Leicester were very helpful and gave me access to their wiring diagrams which was a godsend)... I never did fix it properly but I found a 'black box of tricks' behind the glove box which housed a couple of miniature relays mounted on a PCB. I think that this was something to CODE feature of the On-board computer which allowed you to immobilise the car and I suspect that there was a bad connection or relay here.