» Site Navigation | | » Recent Threads | | 1999 M3 Swap 09-07-2023 10:10 PM 05-02-2024 08:18 PM 6 Replies, 405,075 Views | | | | | 09-15-2011, 01:11 AM | #1 | Member Join Date: Sep 2010 Location: Keller,Texas Posts: 55 | S52 Swap Hard Start Issues... So Ive been trying to work out the little bugs on my S52 swapped Ti and here is one I'm having a hard time figuring out. Ive read lots of posts/threads about it possibly being a ECM problem, FPR problem, a leaking injector problem, or a CPS problem. All sensors are Brand New, New CPS, New Cam Sensor, New Knocks, New O2, New 255LPH fuel pump. No check engine light and yes it works. I swapped 413 ECUs with a friends. No change. I installed a known good set of injectors with new seals. No change. I swapped the stock fuel pump back in place of the 255lph unit. No change. I installed a known good stock OBD1 fuel rail w/ FPR. No change. I installed an OBD2 fuel rail w/ aftermarket FPR set to 51psi per Bentley. I assume this deletes the anti-drain back function of the factory FPR so the internets say to wait 3 seconds for the fuel pump to prime. No change. The fuel pump doesn't initially prime but does pulse when cranking. So I wired it to a relay switched on with the ignition. Then it loads up and when it finally hits there's usually a loud bang followed by a 4 foot flame that shoots out the exhaust. So I don't think its a fuel problem ... What are the odds that I got a bad CPS out of the box and how do you check that ?? Any suggestions ?? TIA. MikeD. | | | 09-15-2011, 01:58 AM | #2 | Senior Member Join Date: May 2005 Location: PA Posts: 1,906 | Mike, are your new sensors oem bmw? or are they autozone brand? I bought some autozone crap (cps) and it was bad from the box. It was also a little shorter (1 or 2 mm) than the oem one. I think the CPS is supposed to see a 5v signal. I don't know why, but that sounds familiar... __________________ | | | 09-15-2011, 02:20 AM | #3 | Member Join Date: Sep 2010 Location: Keller,Texas Posts: 55 | I bought them from Pelican...I dont think it was OEM but another. Ill have to find my receipt to confirm. Guess I can swap in a known good used OEM CPS and see if there's any change. Thanks ! MikeD. | | | 09-15-2011, 09:33 AM | #4 | Moderator Join Date: Mar 2007 Location: Maryland Posts: 3,220 | Sounds like EWS | | | 09-15-2011, 12:35 PM | #5 | Senior Member Join Date: Nov 2010 Location: Potomac Falls VA DMV Posts: 1,794 | Yeah. Go to the dealer and get the EWS realigned. Oh I think there is a member on here that does it Sent from my iPhone using Tapatalk __________________ Im guessing im the youngest member on here with a S52 power'ed Ti at 16 years old! | | | 09-15-2011, 02:44 PM | #6 | Member Join Date: Sep 2010 Location: Keller,Texas Posts: 55 | Not EWS cause I am driving it.... | | | 09-17-2011, 10:25 PM | #7 | Junior Member Join Date: Feb 2011 Location: Concrete Jungle Posts: 28 | how does it run once it's started? that 4 foot flame is the clue | | | 09-18-2011, 11:20 AM | #8 | Member Join Date: Sep 2010 Location: Keller,Texas Posts: 55 | Update...I ohm'd out the new cps and it was way out of spec. I installed a known good BMW cps and it cranked much better but was backfiring worse than before. Ultimately it was the EWS...Cut pin 7 and it now fires right up like its supposed to. Thanks guys for help ! Cheers ! MikeD. | | | 09-18-2011, 01:44 PM | #9 | Junior Member Join Date: Feb 2011 Location: Concrete Jungle Posts: 28 | That seems really strange, EWS is usually crank and no start at all. | | | 09-18-2011, 01:55 PM | #10 | Member Join Date: Sep 2010 Location: Keller,Texas Posts: 55 | Yeh thats what I thought...This isnt my first swap and usually they wont start at all. | | | 09-18-2011, 04:42 PM | #11 | Moderator Join Date: Mar 2007 Location: Maryland Posts: 3,220 | Quote: Originally Posted by BMW_Hatchback Sounds like EWS | Quote: Originally Posted by slow_ti Yeah. Go to the dealer and get the EWS realigned. Oh I think there is a member on here that does it Sent from my iPhone using Tapatalk | Quote: Originally Posted by HyperMikeD Not EWS cause I am driving it.... | Quote: Originally Posted by HyperMikeD Update...I ohm'd out the new cps and it was way out of spec. I installed a known good BMW cps and it cranked much better but was backfiring worse than before. Ultimately it was the EWS...Cut pin 7 and it now fires right up like its supposed to. Thanks guys for help ! Cheers ! MikeD. | Quote: Originally Posted by HyperMikeD Yeh thats what I thought...This isnt my first swap and usually they wont start at all. | Glad the info worked for you. Usually EWS will crank and the fuel pump will prime, but it shouldn't turn over. I've never heard of clipping EWS II though | | | 09-19-2011, 02:21 AM | #12 | Member Join Date: Sep 2010 Location: Keller,Texas Posts: 55 | Yeh its a bastard child of about 5 different cars...The EWS wire wasn't even green/white it was a violet/grey on the engine harness side but on the car side it was correct. Really weird. | | | | Currently Active Users Viewing This Thread: 1 (0 members and 1 guests) | | Posting Rules | You may not post new threads You may not post replies You may not post attachments You may not edit your posts HTML code is Off | | | |