Gutless 1986 BMW 520i

[rtasker]

Hi,
I have recently been given the above car, and was wondering if anyone has any ideas on what might cause it to have such desperately poor performance.

At first I thought it might be valve damage caused by running on LRP, but a compression test showed ~13.5 bar on all 6 cylinders. This is pretty good I think.

The car has done 97,000 miles, and has been very well looked after, with a full BMW service history. It runs very smoothly, with no hint of a misfire.

In the event that I can't trace the problem myself, does anyone know of any independent BMW specialists in the Bristol area?

Thanks for any help

[mustard]

You positive its not running fine, theses are heavy cars and only have 129bhp giving a top speed of 118mph(114 for auto) and 0-62 in 11.4secs (13.3 for auto) so its never going to feel remotely fast

[rtasker]

It is an automatic, but I'm sure it's not right. Pulling out of junctions can be a nerve wracking experience, as it labours across the road with oncoming traffic approaching.

Not sure about 0-60 times, but I did time it from 60-80 in 20 seconds.

I would have thought that 129bhp should give respectable (if not blistering) performance, but it does feel like the slowest car on the road, unable to keep up even with 1.0 litre Micras and the like.

[rtasker]

mungo said:

The fact it's an 86 520i could be a good clue to it being gutless

Ooh, so unkind

I have previously only owned Fords, and was looking forward to a car that was at least well engineered, even if it's not exactly high performance. It is nice to drive something that doesn't feel like the next expensive failure is imminent, but slightly disappointing to feel that something has already gone wrong.

I have been advised that it could be a sensor such as the air mass flow sensor or crank position sensor, but I'm not sure how to test these things. I have looked at the air filter, and this is clean and looks quite new.

[scoobz]

just be thankful its not a 518i - you could run faster...

jack up number plates and fit faster car. that should fix it.

[fixedwheelnut]

The 520i's are notorious for lack of power especially low rev torque, to get anywhere in one means really revving the engine and can result in poorer fuel economy than a 2.5 lump, just have to get used to it they are still strong cars just bloody slow.

[turbobloke]

Only gutless - has it been tuned?

[mustard]

scoobz said:

just be thankful its not a 518i - you could run faster... jack up number plates and fit faster car. that should fix it.

Though neither is much cop, think i'd rather have a gutsy 8v 4 pot rather than a lip risted 6, (hence why the dropped the E30 320 Touring shortly after the 318 touring was introduced) though its a difficult call!

In its day the period chariot of choice was the 528i the accountant and bank managers favourite

[rtasker]

OK, I'm detecting a certain concensus of opinion regarding the 520i performance. I still think mine must be worse than most though as it feels more like 40bhp, rather than 129.

I once had a 1.8 CVH engined Sierra, with 90 something bhp, and that was bad, but not this bad. I'll try to get a 0-60 time for you this evening. I'm sure you'll all enjoy that!

[rtasker]

Well it seems you may all be right. I have just done a 0-60 run, and managed it in about 13 seconds. So I guess that's it then. At least it seems there is nothing that needs fixing. I'm not sure if I can live with such sedate performance though.

Thanks all for the advice anyway.

[Pentoman]

Being an auto it could well be a problem with the gearbox - does it rev to the redline, does it kick down properly?

Try playing with the gear selector lever to hold it in gear and things may improve.

Mercedes autos of the same era start off in 2nd gear (which goes to around 60mph) so take off is slow unless you use kickdown or force a start in 1st by shifting the lever to '2'.

I too don't reckon this should be quite as slow as you describe!

Russell
190E x2, '62 Elan

[rtasker]

Yes, I was wondering about the gearbox. I've not driven the car for a couple of weeeks, and when I started the car yesterday evening it really struggled to reverse out of the drive. I had my foot flat to the floor, and the engine revved to about 2500 rpm but the car barely moved. Then, as I pulled forward it laboured for a while again, and then picked up. This is how it normally behaves when first started, but it was worse than usual last night.

On my 0-60 run last night, the engine revved all the way to the red line, and I had to ease off the throttle slightly to allow it to change up a gear. So I think the kick down is operating OK.

[pentoman]

Not sure how accurate you were being with your description but, there should be no need to ease off the throttle for it to change gear, it should change up if the gearbox is properly working/adjusted even in kickdown or full throttle..

(sorry for being picky!)

Russell

[rtasker]

Well, what I meant was that as the tachometer swung up to the red line I eased the accelerater pedal up, just enough to release the kick down button. There was a jerk as the gearbox found the next gear, and then I pushed the pedal back to the floor and held it there until the speedo registered 60mph. Pushing the pedal back to the floor didn't result in the gearbox changing back into first gear.

As you suggest, I'll try pulling away with the gear selector in 2nd (and first?) to see how that affects things.

Cheers,
Richard

[r988]

Everything you ever wanted to know about BMWs especially E28s
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