_Matt_ 42 Report post Posted May 23, 2012 Go! First noticed this in the weekend. Engine just stalled after hard braking. It stalled again this morning under pretty standard braking so this evening I fully cleaned out the ICV and cleaned and recalibrated the afm. It now idles smoothly and is a lot more responsive but still cuts out after hard braking. Other things to check are - fuel filter - battery terminals - earth points - leaks around brake master cylinder Anything else I should check? E28 528i Quote Share this post Link to post Share on other sites
OP6 27 Report post Posted May 23, 2012 Check that your fuses and relays are tight and have good connections. Quote Share this post Link to post Share on other sites
hotwire 352 Report post Posted May 23, 2012 Booster hose leaking? Quote Share this post Link to post Share on other sites
andrewm 236 Report post Posted May 24, 2012 Was battery terminals for me, look perfect and far tighter than finger tight but when i took it out to charge to 100%, sanded terminals and put vaseline on and really tightened it up, no more issues Quote Share this post Link to post Share on other sites
oscar90 0 Report post Posted May 24, 2012 one of the plugs under my steering column had come slightly loose, engine and tach would just die randomly when jabbing the brakes etc...another option Quote Share this post Link to post Share on other sites
_Matt_ 42 Report post Posted May 24, 2012 Interesting, it must have something to do with the brake system as the idle drops a bit if a hold the brakes when stationary. The wired thing is, if I'm stationary and slam the brakes, nothing really happens but if i'm moving, even at walking pace and slam the brakes it stalls. The terminals feel fine but I'll check again tomorrow. If it's the brakes I wouln't know where to begin checking haha, and I'm sure it's had leaks since I've owned it Quote Share this post Link to post Share on other sites
Surge 1 Report post Posted May 24, 2012 (edited) E30's have a 50amp fuse that's under the heatshrink (at least in 325i) in the boot, off the battery - they can go/have poor connection and cause a whole host of problems like that. Another one... the plug from the firewall (ECU) to motor (c101 in E30...) can cause all sorts of problems. How I found out what caused my issues was jiggling the wires while the car was running till I rattled a bunch of them and then the car died... Do check your IGN switch too. Edited May 24, 2012 by Surge Quote Share this post Link to post Share on other sites
BM WORLD 1283 Report post Posted May 24, 2012 did you do an engine swap recently , check the earth straps on the left engine mount side and the small one on the back of the rocker cover going back to the firewall. your injectors earth through the engine block. also check the bolts on the inlet manifold that the injectors earth to. just doubel check all electrical conections , is your ICV working properly (should respond quickly if put under load at idle) like turning the power steering quickly from side to side , lights on a/c on , push brake pedal lots and fast. have you got an alarm arr all the ignition conections well connected ?? Quote Share this post Link to post Share on other sites
_Matt_ 42 Report post Posted May 24, 2012 did you do an engine swap recently , check the earth straps on the left engine mount side and the small one on the back of the rocker cover going back to the firewall. your injectors earth through the engine block. also check the bolts on the inlet manifold that the injectors earth to. just doubel check all electrical conections , is your ICV working properly (should respond quickly if put under load at idle) like turning the power steering quickly from side to side , lights on a/c on , push brake pedal lots and fast. have you got an alarm arr all the ignition conections well connected ?? I'll thourouhly go through this list and get back you you. It's still the original m30b28 and I have no alarm. Quote Share this post Link to post Share on other sites
_Matt_ 42 Report post Posted May 27, 2012 (edited) did you do an engine swap recently , check the earth straps on the left engine mount side and the small one on the back of the rocker cover going back to the firewall. your injectors earth through the engine block. also check the bolts on the inlet manifold that the injectors earth to. just doubel check all electrical conections , is your ICV working properly (should respond quickly if put under load at idle) like turning the power steering quickly from side to side , lights on a/c on , push brake pedal lots and fast. have you got an alarm arr all the ignition conections well connected ?? So I've checked the engine mount earths, injector earths, rocker cover earth, made sure all fuses and relays have good connections. Battery and terminals are tight and clean. There are no loose connections around the ignition yet I still have the problem. An important thing I noticed when going for a test drive was... No matter how fast I am going if I hit the brakes and stop then release the pedal (in quick succession of course) the engine will not stall and not even seem to drop below idle speed. But No matter how fast I am going if I hit the brakes and stop without releasing the pedal it will instantly stall. I guess this possibly eliminates that it's could be something loose or moving... Edited May 27, 2012 by _Matt_ Quote Share this post Link to post Share on other sites
sp8s 1 Report post Posted May 27, 2012 Brake power booster? leaking air. Dont know if they have one or not Quote Share this post Link to post Share on other sites
hotwire 352 Report post Posted May 27, 2012 Brake power booster? leaking air. Dont know if they have one or not Yep, my suggestion further back was booster hose but also meant to suggest booster itself:- Quote Share this post Link to post Share on other sites
BM WORLD 1283 Report post Posted May 27, 2012 Yep, my suggestion further back was booster hose but also meant to suggest booster itself:-e28 has the hydrolic booster brake system so power steering pump could be dragging the power out of the engine.how good is your p/s fluid, what speed does your car idle at , when sitting or working the steering , pushing the brake pedal fast , lights on , a/c on etc Quote Share this post Link to post Share on other sites
hotwire 352 Report post Posted May 27, 2012 ^^^^ ok stand corrected. Obviuosly I never looked at the booster in the brief time I had an E28 Quote Share this post Link to post Share on other sites
_Matt_ 42 Report post Posted May 27, 2012 e28 has the hydrolic booster brake system so power steering pump could be dragging the power out of the engine. how good is your p/s fluid, what speed does your car idle at , when sitting or working the steering , pushing the brake pedal fast , lights on , a/c on etc it idles around 650 and as soon as I steer left to right it starts dropping... with ac on steering becomes harder and idle drops to around 550-600 I forgot to pump the brakes at the same time but the idle does drop a bit when I pump the brakes (did that earlier today) Quote Share this post Link to post Share on other sites
BM WORLD 1283 Report post Posted May 27, 2012 it idles around 650 and as soon as I steer left to right it starts dropping... with ac on steering becomes harder and idle drops to around 550-600 I forgot to pump the brakes at the same time but the idle does drop a bit when I pump the brakes (did that earlier today) maybe idle should be about 750rpm, maybe adjust it up , or is there a reason its idling that low?? vac leak? , tps not working? afm worn out , afm fine tune screw set to lean?? Quote Share this post Link to post Share on other sites
_Matt_ 42 Report post Posted May 27, 2012 (edited) maybe idle should be about 750rpm, maybe adjust it up , or is there a reason its idling that low?? vac leak? , tps not working? afm worn out , afm fine tune screw set to lean?? The idle has been 650 since I've owned it. I have adjusted the AFM so the arm is running on a fresh surface (it works great when blipping the throttle) I could adjust the idle using the screw by the IVC but that would just be a temporary solution. vac leak, probable...but where do I start? haha. tps, the car does shudder when releasing the accelerator and the idle fluctuates a bit so maybe this is a problem...I do have a spare from a B34 I could swap it over and try that out. Edited May 27, 2012 by _Matt_ Quote Share this post Link to post Share on other sites
_Matt_ 42 Report post Posted May 29, 2012 Decided to replace the TPS and briefly thought it fixed the issue but after a few fast stops it stalled again. I thought of replacing the PS Pump because the idle drops when steering quickly and braking fast but it also drops quite dramatically when the AC is on. Maybe the TPS just needs adjusting? Interesting thing is since replacing the TPS the brake warning light illuminates when the ignition Is on and the brake pads light briefly illuminates when I turn over the engine. Quote Share this post Link to post Share on other sites
polley 916 Report post Posted May 29, 2012 A vacuum leak will generally make the engine idle higher, not lower. Quote Share this post Link to post Share on other sites
_Matt_ 42 Report post Posted June 10, 2012 (edited) Can't wait for this to sit in my garage and be a project car :/ went trough the small easy stuff first. - adjusted AFM - adjusted idle - ordered thermostat in case temp reading causes wrong fuel mixture etc - replaced fuel pressure regulator - tightened PS pump belt - whatever else I mentioned above... Car runs nicer, still stalls under hard braking but not quite as easily which it a positive anyway. I did a thorough inspection of the brake system and I may have found the problem. The connection between the Hydraulic servo unit and the master cylinder has a nice healthy leak (PS fluid). which has been dripping on to the chassis rail, it manages to make its way under the wheel arches making a big mess. I guess ill replace the main o-rings are on the plunger of the servo unit. There are a few write up's on how to do this but where can I find the O-Rings? I think i need these: TIA Edited June 10, 2012 by _Matt_ Quote Share this post Link to post Share on other sites
_Matt_ 42 Report post Posted June 19, 2012 replaced the thermostat and It doesn't seems to have fixed the problem...touch wood. Ill still fix the servo unit though Quote Share this post Link to post Share on other sites
