R3VLimited Forums

Go Back   R3VLimited Forums > E30 Technical Forums > Engine & Drivetrain > M20

Reply
 
Thread Tools Search this Thread
Old 05-06-2019, 11:58 AM   #1
ryan.of.peachey
Noobie
 
ryan.of.peachey's Avatar
 
Join Date: Apr 2019
Location: US
Posts: 37
No spark, tach not moving while cranking

I've got an '88 325i vert with a no start, no spark issue. I've replaced the following parts: spak plugs and wires, cap and rotor, coil, CPS. I've got 12 volts at the coil with ignition on, and the engine cranks over well, but no spark. Also the tach stays at 0 while cranking. Would this indicate a bad CPS, even though it's a new part? Thanks.

Sent from my SM-G960U using Tapatalk
__________________
1988 Alpinweiss 325i Convertible
ryan.of.peachey is offline   Reply With Quote
Old 05-06-2019, 05:11 PM   #2
MrBurgundy
No R3VLimiter
 
MrBurgundy's Avatar
 
Join Date: Mar 2012
Location: 33.8170 N 118.0373 W
Posts: 3,714
At the CPS make sure you're getting 12v and a ground. If you are, crank the car and verify that the CPS is sending a 5v pulse out.
__________________
Quote:
Originally Posted by wholepailofwater View Post
Q


WTB: Dove Grey e36 Front Door Panels (2 door)
MrBurgundy is offline   Reply With Quote
Old 05-08-2019, 05:52 PM   #3
ryan.of.peachey
Noobie
 
ryan.of.peachey's Avatar
 
Join Date: Apr 2019
Location: US
Posts: 37
The CPS is registering over 800 ohms, and I think it should be around 540, right?

Sent from my SM-G960U using Tapatalk
__________________
1988 Alpinweiss 325i Convertible
ryan.of.peachey is offline   Reply With Quote
Old 05-16-2019, 10:52 AM   #4
MrBurgundy
No R3VLimiter
 
MrBurgundy's Avatar
 
Join Date: Mar 2012
Location: 33.8170 N 118.0373 W
Posts: 3,714
Quote:
Originally Posted by ryan.of.peachey View Post
The CPS is registering over 800 ohms, and I think it should be around 540, right?

Sent from my SM-G960U using Tapatalk
Yeah an OEM one will read that, but some aftermarket ones I think will read a little higher than that.

But what I'm saying is verify that you're getting power, ground and signal coming out of the CPS.
__________________
Quote:
Originally Posted by wholepailofwater View Post
Q


WTB: Dove Grey e36 Front Door Panels (2 door)
MrBurgundy is offline   Reply With Quote
Old 05-16-2019, 05:59 PM   #5
ryan.of.peachey
Noobie
 
ryan.of.peachey's Avatar
 
Join Date: Apr 2019
Location: US
Posts: 37
I pinned out the DME and I'm getting a signal from the CPS at pins 46 and 47. The only thing that seemed wrong was I couldn't get the main relay to click when I jumped pin 36 to ground. Also the coil main post to 15 is reading close to 7k ohms, so I think the coil may be bad...even though its new..

Sent from my SM-G960U using Tapatalk
__________________
1988 Alpinweiss 325i Convertible
ryan.of.peachey is offline   Reply With Quote
Old 05-21-2019, 09:00 AM   #6
S.J.1981
Member
 
S.J.1981's Avatar
 
Join Date: Dec 2018
Location: Germany
Posts: 48
Quote:
Originally Posted by MrBurgundy View Post
Yeah an OEM one will read that, but some aftermarket ones I think will read a little higher than that.

But what I'm saying is verify that you're getting power, ground and signal coming out of the CPS.
Not sure about you guys in the US, but here in Germany when i was looking for a new CPS, several popped up, a few of them were rated at 800 ohms, some were 550 ohms, pictures of both sensors looked identical but online pics maybe just a sample or incorrect.
S.J.1981 is offline   Reply With Quote
Old 05-21-2019, 09:36 AM   #7
ryan.of.peachey
Noobie
 
ryan.of.peachey's Avatar
 
Join Date: Apr 2019
Location: US
Posts: 37
Either way I got a new CPS from BMW and it checks out at 530 ohms. Still trying to track down the no spark. Thinking it may be a bad connection to main relay.

Sent from my SM-G960U using Tapatalk
__________________
1988 Alpinweiss 325i Convertible
ryan.of.peachey is offline   Reply With Quote
Old 05-23-2019, 02:24 AM   #8
S.J.1981
Member
 
S.J.1981's Avatar
 
Join Date: Dec 2018
Location: Germany
Posts: 48
Quote:
Originally Posted by ryan.of.peachey View Post
Either way I got a new CPS from BMW and it checks out at 530 ohms. Still trying to track down the no spark. Thinking it may be a bad connection to main relay.

Sent from my SM-G960U using Tapatalk
Best method of testing sensors is to pull the DME pins and to verify that whatever the sensor output is, the DME is getting the same signal.

Have you tried to swap the DME and ECU relais? If you suspect a loose/bad connection, try to "jiggle" the wires a bit and see if it makes a difference.

Since you replaced the CPS and Spark Plug wires (which comes with another sensor) are you certain that you did not mix up the connections near the OBD port?
S.J.1981 is offline   Reply With Quote
Old 05-23-2019, 07:33 AM   #9
ryan.of.peachey
Noobie
 
ryan.of.peachey's Avatar
 
Join Date: Apr 2019
Location: US
Posts: 37
Thanks for your reply. I'm certain I got the wires hooked up correctly. I even tested the ECU plug to make sure I'm getting a signal from the CPS to the ECU. I have tried swapping out ECUs also, which didn't have any effect. I have 12 volts at the coil, so I think the ignition switch is good. I replaced the main relay, but I need to do more testing to make sure it's getting power I guess. I had my wife listen for it to click when turning the ignition on and there was no click.

Sent from my SM-G960U using Tapatalk
__________________
1988 Alpinweiss 325i Convertible
ryan.of.peachey is offline   Reply With Quote
Old 05-23-2019, 09:10 AM   #10
MrBurgundy
No R3VLimiter
 
MrBurgundy's Avatar
 
Join Date: Mar 2012
Location: 33.8170 N 118.0373 W
Posts: 3,714
You're better off putting a finger on the relay.

You'll feel the click more than you'll hear it,.
__________________
Quote:
Originally Posted by wholepailofwater View Post
Q


WTB: Dove Grey e36 Front Door Panels (2 door)
MrBurgundy is offline   Reply With Quote
Old 06-01-2019, 10:31 AM   #11
ryan.of.peachey
Noobie
 
ryan.of.peachey's Avatar
 
Join Date: Apr 2019
Location: US
Posts: 37
Finally got it started. Used some wires to jump the main relay and it fired right up. I guess I got a bad part when I bought the relay...either way a new one is on order from Turner.

Sent from my SM-G960U using Tapatalk
__________________
1988 Alpinweiss 325i Convertible
ryan.of.peachey is offline   Reply With Quote
Old 06-08-2019, 12:32 AM   #12
digger
R3V Elite
 
Join Date: Nov 2005
Location: Sydney, Oz
Posts: 4,274
ive got a similar issue, cranks well but no spark but occasionally runs for a couple second and cuts out.

im also expecting crank sensor, cam sensor or relay. im using an after market ECU so logged a cranking no start sequence which showed a SYNC error.

anyone got main relay PN handy?
__________________
89 E30 325is Lachs Silber - currently M20B31, M20B33 in the works, stroked to the hilt...

new build thread http://www.r3vlimited.com/board/showthread.php?t=317505

digger is offline   Reply With Quote
Old 06-09-2019, 08:56 AM   #13
ryan.of.peachey
Noobie
 
ryan.of.peachey's Avatar
 
Join Date: Apr 2019
Location: US
Posts: 37
Here you go...

https://www.turnermotorsport.com/p-1...IegaAn8i8P8HAQ

Sent from my SM-G960U using Tapatalk
__________________
1988 Alpinweiss 325i Convertible
ryan.of.peachey is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -7. The time now is 10:53 PM.


Powered by vBulletin® Version 3.8.10
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Copyright 2004 - 2020 R3VLimited LLC