DASC CUTTING OFF PROBLEM

[naychurkal]

Ok guys im new to this site but im not sure if anyone here knows me.. I'm DOUG and im part of EUROWERKZ and I recently came out on PERFORMANCE BMW in Feb 06. Yellow widebody bmw 318is.... OK my question is i swapped my 92 318is engine with a M44 98 318ti which came with DASC already. The problem im having is that the car keeps cutting off at around 5200 rpms. I check fuel pressure and its right where its supposed to be 80psi. I cant seem to find what the problem is. I heard of some guy in FL that only deals with 318DASC engines, and he said he could flash my ECU and take care of that problem, something to do with my speed sensor. But I cant remember his name or the name of the shop. If anyone has any information that could help me please email me, I would really appreciate it. CHECK MY CAR AT http://www.eurowerkz.com/gallery/album02

I was also wondering if anyone has the installation manual and parts list for the DASC. thanx

Any one from this area (NJ, NY, DE, PA, VA) and would like to join EUROWERKZ let me know. email me @ DOUGF7@COMCAST.NET

[mischief]

sweet ride you have there

[DustenT]

Welcome Doug. Can explain what you mean when you say "cutting off"? Does the engine quit? Does it stop revving? Does it sound like a misfire? Always at the same RPM? How does it drive below 5200 rpms? Do you have a check engine light?

I remember seeing your car in the magazine. Quick question: Why do you have a BOV installed on your DASC? Do you still have the by-pass valve installed? Post some engine bay pictures please.

Thanks!

[naychurkal]

How are you DUSTEN?..... Well the cutting off feels like spark cut off. at the same rpms everytime. But if the engine is cold it doesnt cut off, its just like hitting the rev limiter but just 1500 rpms earlier, Its weird man. Before cutting off the car drives fine, pulls pretty good. Well like i said the BOV came on there, i know it cant be there, i have a huge vacuum leak from it, thats why i was wondering if anyone had the parts list so i know what to order and pricing list, i did see it on another post but i couldnt look at the pdf files.

[DustenT]

Originally Posted by naychurkal

How are you DUSTEN?..... Well the cutting off feels like spark cut off. at the same rpms everytime. But if the engine is cold it doesnt cut off, its just like hitting the rev limiter but just 1500 rpms earlier, Its weird man. Before cutting off the car drives fine, pulls pretty good. Well like i said the BOV came on there, i know it cant be there, i have a huge vacuum leak from it, thats why i was wondering if anyone had the parts list so i know what to order and pricing list, i did see it on another post but i couldnt look at the pdf files.

I would start by replacing your plugs and your plug wires (if you haven't already).

It's possible that the vacuum leak from the BOV is causing the cut-off too. Incoming air is measured at the mass air flow sensor so if any of that leaks out via a vacuum leak, the car will lose power from an improper fuel mixture. It could be that the leak gets worse under high boost/high rpms. What does your boost gauge read before and after the engine cuts out?

[naychurkal]

well the boost gauge says 10psi but im guessing it says that because of the vacuum leak... i know the vacuum side of the gauge is too high, its reading -10psi. the wires i havent changed the plugs i have. well but why would it not cut off when the engine is cold???? i just dont know what to do man. i was thinking about getting rid of the engine with the supercharger and getting something else, but i like that fact that its different, alot of people around me have the m conversion, so i wanted to do something unique at least around here.

[mooseheadm5]

If the ECU does not see vehicle speed it might just rev limit the motor. I know the 6 cylinders work this way. You may need to feed the ECU a speed sensor signal to correct this. Does your speedo work? If so, the sensor works so it is just the ECU not receiving the signal. I think the ECU is programmed this way to prevent over-revving in neutral.
-Paul

[naychurkal]

but then again why would it not cut off if the car is cold ????? thats wat i dont understand ! you do have a good point tho.. maybe the guy i spoke with is right about him reflashing the ecu not to read this safe mode feature.

[DustenT]

Originally Posted by naychurkal

but then again why would it not cut off if the car is cold ????? thats wat i dont understand ! you do have a good point tho.. maybe the guy i spoke with is right about him reflashing the ecu not to read this safe mode feature.

There is no safe mode on our DME. Metal expands when it gets hot. A metal crack could expand larger when it gets hot. I'd take it to a mechanic and have them take a look. Misting water might help to locate a leak/crack.

I can rev past 6000 rpms in neutral. My car used to be an automatic, so it thinks it's in neutral all the time, proving that the speed sensor doesn't adjust rpm redline.

[mooseheadm5]

Like I said, don't know about the 4 bangers. For the 6 cyl cars, TMS/Conforti makes a speed sensor delete chip that allows you to rev your car past an artificially low redline should you have any reason to have your speed sensor disconnected. No speed sensor on a 6 banger = ~4500rpm redline (might be under load, but I am not sure.) By "in neutral" I meant "while not moving." The DME has no idea when a manual car is in neutral or in gear (the fact that your car revs out "proves" nothing, really, but points to your DME not having this "feature".)
-Paul

[Mendi3]

Originally Posted by naychurkal

How are you DUSTEN?..... Well the cutting off feels like spark cut off. at the same rpms everytime. But if the engine is cold it doesnt cut off, its just like hitting the rev limiter but just 1500 rpms earlier, Its weird man. Before cutting off the car drives fine, pulls pretty good. Well like i said the BOV came on there, i know it cant be there, i have a huge vacuum leak from it, thats why i was wondering if anyone had the parts list so i know what to order and pricing list, i did see it on another post but i couldnt look at the pdf files.

I have a 95ti with a DASC and had the exact same problem. It went for months until we figured out. I had rebuilt the engine and when put the engine back for some reason the crank sensor was not sitting in the right place, causing the engine to cut off at about 5500 RPMs. After we made sure the crank sensor was in the right position, the problem went away.

I hope this helps.

[naychurkal]

but how does it not cut off when the car is cold, and also its always at the same 5200 RPMS. Does anyone know the guy that works with this kind of engine and supercharger from florida??? i cant remember his name. I wen to my local mechanic and he checked my ecu, i have a code for a speed sensor malfunction, and a couple of missfire codes. when he resets everything the car doesnt cut off........ maybe thats something to START ?

[mooseheadm5]

Speed sensor malfunction code? Hmm...
-Paul

[mohaughn]

I'm guessing by the Florida guy you mean Nick G with Technique Tuning.

He does specialize in FI BMWs and the m44 w/DASC is one of the cars that he will do custom tuning for. http://www.techniquetuning.com/

[ClubSport]

I think you are feeling timing retard. You need more fuel, more octane, or colder plugs. This is why you don't feel it when it's cold, but once the cylinder head is good and hot, the ECU senses knocking and retards spark timing. I used to feel this at 5500 rpm, a dramatic drop off in power. Colder plugs helped a little. Toluene helped a lot. Finally being able to control my air/fuel ratio down to 12:1 helped a lot. With 10psi and a RRFPR on stock injectors I doubt you're getting very good air/fuel ratios.