Poor Performance 520i

[matrox02 0]

Hi guys so i recently purchased a 520i with really low power below 3krpm, it almost feels like im driving with the hand brake on , knowing the few things i do.. I got rid of the cat converter, and done a general service, including replacing the fuel filter, however its still piss poor at best in the cold when trying to pull away ( iv driven other 520i and this is just reallly bad ), Does anyone know what the resistance values for the Siemens AFM should be? that would be my next stop as iv been told that although the symptoms show like a bad vanos seal ( what ever that means ?? ) its not likley on the this model, Oh, Its a 1996 e34 520i Individual at the moment im not seeing any check engine light, so im not sure if the bulb is even there???

Or does anyone have any other pointers or know where else i should check, Otherwise the car starts quite nicely and cruises fine at 100

[yng_750 247]

could be afm or cam/crank position sensors, or o2 senors.

or C191 plug upsetting the injectors.

just a few options that spring to mind

[Cab 148]

Sounds like your AFM to me. My e28 had this problem and I literally took my afm off, cleaned it, reassembled it and the problem went away for good.

[Arma 134]

Get it scanned. My 520i had similar problems and it turned out to be a camshaft position sensor. Some fault codes should show up during the scan.

Edited June 25, 2013 by Arma

[_ethrty-Andy_ 2132]

My 520i when it was a 520i was a total slug too, 318i autos were quicker. its partly just a small engine in a big car. but yep get it scanned, that will tell you for sure. the facility is there in your car so use it!

[matrox02 0]

Hi guys, thanks for the info, yeah i booked my car in for a scan, I had cleaned the seimens AFM and made a very small improvement, though the c191 plug.. where is it? or.. rather what type of plug is it?, and ill keep you posted otherwise , its a really nice car and id hate to have picked it up for this cheap only to find a major engine problem.. though at the moment it doesnt appear to be one, though while mucking around the car i was a little concerned to find that it looks as though one of the control modules appears to have been tampered with, though opening the one up and looking around it shows that no caps are bloated and no hardware is stuffed, no dry solder and such, so yeah.. maybe its the AFM, but ill wait and see now

nvm about the c191, I used the power of google, and ill have a look see tomorrow during a nice day. ( Ie Dont change your mind auckland weather! )

Edited June 25, 2013 by matrox02

[matrox02 0]

so i took it to get scanned, No codes, their scanner for some reason couldnt connect, on another note, after the scan ITS NOW OVER HEATING! the low hose is ice cold and the top hose hot as hell, so likley a blocked radiator/ stuck thermostat or water pump is shot?, and at worst.. a blown head gasket??

what was a nice cheap bimmer.. is now turning into a nice expensive one..

Oh no water in oil that i can see yet, and no oil/white stuff on oil cap either.

Edited June 26, 2013 by matrox02

[_ethrty-Andy_ 2132]

so i took it to get scanned, No codes, their scanner for some reason couldnt connect, on another note, after the scan ITS NOW OVER HEATING! the low hose is ice cold and the top hose hot as hell, so likley a blocked radiator/ stuck thermostat or water pump is shot?, and at worst.. a blown head gasket??

what was a nice cheap bimmer.. is now turning into a nice expensive one..

Oh no water in oil that i can see yet, and no oil/white stuff on oil cap either.

rotten luck, wont have come from the scan unless they tried to plug the machine in a wierd place maybe why they couldnt get a read???

No such thing as a nice cheap bimmer though imo ha

[matrox02 0]

i did sit idle for ages before parking the car to do diagnostics, and they did start the car and rev it ( not hard though ) , when i stopped to let it cool, i gave them a ring and asked them if they noticed it dropping water/overheating, when they told me that the boy noticed that it was dropping water from the bottom of the radiator i would have thought they would have warned me prior to me leaving but oh well, so i dont think they broke it, so its likley considental, or a problem just waiting to happen, I will pull the rad and flow test it, if thats fine then ill pull the pump and replace that with the thermostat, and hope for the best.....coz in my experience a cold lower hose and over heating generally means blocked core , cold top hose means bad thermostat..

[matrox02 0]

Update: new Rad needed, found next to no water in it, and apon filling it back up and bleeding it i found there to be a leak between the seal of the expansion tank and the core, so Im just replacing it, and i hope thats the end of the over heating dilemma, Iv still got to find the missing/ no power issue though, wiggeling the c191 ( the one i assume is the c191 ) doesnt cause the car to do anything funny, though there could be a resistance there that im not aware of, and i havnt been able to find a test cas/afm to test it out , and euro parts wreckers want new prices for 2nd hand parts.. so ... yeah, may be a while till i figure out whats going on.

[BM WORLD 1283]

can do a new rad for you

$260

http://www.trademe.co.nz/motors/car-parts-...n-608439690.htm

they fit fine in a e34 520i

[matrox02 0]

can do a new rad for you

$260

http://www.trademe.co.nz/motors/car-parts-...n-608439690.htm

they fit fine in a e34 520i

Got one for 220 today, only problem is though, it seams as thought the seal for the cap isnt sealing right, its letting me squeeze the hose and you can hear the air come out, just outa interest i doubled the thickness of the seal and now it seals fine, im wandering if this chinese one has the measurements slightly out or something, but yeah, new rad fitted,and she now doesnt over heat, but im s little suspect the pressure int he hoses, and the heater in the car doesnt seam to blow how air :S so i wander if there is an air pocket still

[matrox02 0]

So..... IM gutted now, I drove it around earlier and had no problems, desided to go out for a bit jumped in the car, and found the car hydro locked, pulled the plugs, all clean as, only cylinder 1 had traces/droplets of water in it, cylinder 3, flooded beyond beliefe, i flicked it over to spit th water out checked it again to find it just as full as before, so.. defo the head gasket also now sludge under oil cap, and i cant do the head gasket myself anymore as i dont have a vanos lock kit, and dont have the odd sockets for the head bolts and cam shafts, so... Anyone know of any good cheapish mechanic that can do the headgasket for me? and im hoping like hell that the head isnt cracked, but how likley is it, and how much would i normally have to fork out for this sorta job???

[yng_750 247]

very high probability the head is cracked, very common for these motors.

TBH you are probably better off getting a new motor, less labor involved and about the same price as a head.

[matrox02 0]

very high probability the head is cracked, very common for these motors.

TBH you are probably better off getting a new motor, less labor involved and about the same price as a head.

On tm i can get a complete package for the 2.5 m50b25 engine, will that be a good repower? its from an e36, comes with the ecu, would that one bolt straight in no issues?

[_ethrty-Andy_ 2132]

On tm i can get a complete package for the 2.5 m50b25 engine, will that be a good repower? its from an e36, comes with the ecu, would that one bolt straight in no issues?

No, but very easy to convert. Just google it there are literally thousands of swapped e30s most with build threads pf varying degrees

[matrox02 0]

No, but very easy to convert. Just google it there are literally thousands of swapped e30s most with build threads pf varying degrees

Apparently I can bolt it straight in, only have to be mindfull of the EWS-II or something, apparently i can get a 94 dme and pop that in and cut a single wire and ave the car run fine ?

[_ethrty-Andy_ 2132]

Ment to say E34 above. No it's not bolt in. You will need to swap sumps arms/mounts oil pickup dipstick and tube over, when you get the e36 engine you will see why. About a hours work to swap over, and make sure you get new gaskets/orings for those bits. Might be a good time to change rear main seal while engine is out too

[yng_750 247]

to be honest it sounds like you are better off just trying to find an engine exactly the same as yours, dont mean to be rude or anything but if you try and swap a different engine in and screw it up you can spends massive amounts of money getting someone else to fix it.

as with all things do plenty of research then take a moment to step back and think about everything then have a go.

also it wouldnt be a bad idea to try to get an engine that comes with ancillaries like the afm and enginebay wiring loom.

that way you eliminate the original issue at the same time.

[Dave@nz 11]

Hi,

As I see it you have two clear paths one is like previous member suggested get another engine exactly same as original for easy replacement.

2nd is to sell it as is try and recoup some of your money move on to another car.

Any other option would not make financial sense.

Hope you dont take this as negative advice.

Dave.

[matrox02 0]

Hey guys, thanks for the advise, and no none of it was rude/ Negative, im just exploring my options, at the moment its looking like a pretty good idea just o have the engine just replaced by a BM Mechanic close by, im still looking for a replacement from another e34, iv been enquiring through email and have had some good leads so far

[yng_750 247]

nice to see the research being done.

if you get stuck in a catch 22 of it costing too much to fix and not being worth selling i would consider flushing the system out and using a bottle of rislone head gasket fix.

I have heard good things about it, does a good job sealing even big cracks and splits, only way it will leak again is if a new crack forms. lasts years apparently.

Still nothing beats a proper fix but $85 at supercheap vs $1K plus. makes sense if your just going to drive it into the ground so to speak.

I would use it on a car i was keeping but wouldn't use it on a car im selling, not because i dont trust it to last because i do.but its just if im honest noone will buy it as they will expect it to blow up at any second, and if i have to be dishonest to sell a car i would rather keep the car and keep my word.

[matrox02 0]

nice to see the research being done.

if you get stuck in a catch 22 of it costing too much to fix and not being worth selling i would consider flushing the system out and using a bottle of rislone head gasket fix.

I have heard good things about it, does a good job sealing even big cracks and splits, only way it will leak again is if a new crack forms. lasts years apparently.

Still nothing beats a proper fix but $85 at supercheap vs $1K plus. makes sense if your just going to drive it into the ground so to speak.

I would use it on a car i was keeping but wouldn't use it on a car im selling, not because i dont trust it to last because i do.but its just if im honest noone will buy it as they will expect it to blow up at any second, and if i have to be dishonest to sell a car i would rather keep the car and keep my word.

Yeah i thought about that, But im not sure that it will remedy a problem this big, it filled cylinder full of water after cranking the engine to spit out the water faster than i could get back from the drivers seat to the engine bay, and i dont want to get caught out if i go on a long drive, but it is still an option if i want to drive it around to work i guess, thats if I can get the cylinder empty long enough to not hydro lock the engine when starting it again haah

[_ethrty-Andy_ 2132]

Those products do work but I'd say it would be a miracle if it fixed this problem. Get an M52B28 in there, you may need some M50 obd1 parts. No point putting a 2L back in there, you will find a 2.8L will be more economical. The 520i pretty much only made to get round registration tax laws that don't exist here

Edited June 29, 2013 by _Ethrty-Andy_

[matrox02 0]

Those products do work but I'd say it would be a miracle if it fixed this problem. Get an M52B28 in there, you may need some M50 obd1 parts. No point putting a 2L back in there, you will find a 2.8L will be more economical. The 520i pretty much only made to get round registration tax laws that don't exist here

Yup, Been thinking of putting a 525i engine in, not the m52 though, and why would i need some obd1 parts? the cars a 96 so should be on obd2 ?

Iv also had conflicting info that if i get an m50b25 engine i can drop that in with out changing the ecu, then others have said i cannot? It would make sense that the b20 ecu doesnt support the b25 engine though