M42club.com - Home of the BMW E30/E36 318i/iS
DISCUSSION => Engine + Driveline => Topic started by: caraddict87 on October 29, 2015, 04:40:27 AM
-
Good morning gentlemen,
This is gonna be a long one so grab some popcorn.
While I am not a very active member on m42club I have been lurking on here for quite sometime. I bought my 1991 318is back in 2004 and starting looking at your forum around 2009ish, so a while. Anyways on to the question at hand.
About 4 years ago my 1991 318is started developing an odd issue where every once in a while the car would crank over then stop, crank then stop, and finally usually the third time it would crank and fire and run fine. This happened for just about 5 months until it finally decided to not crank anymore. When this happened I figured that the battery just died and i needed a new one. so off i went to get a new battery and all was well, or so i thought. I drove it for another month then stored it for the winter by taking the new battery out of it and leaving it on a battery tender all winter.
Come spring time popped the battery in and VROOM started like a champ.."Great all my problems are behind me".
Fast forward 2 months and the same issue starts arising vehicle wont start first time and eventually wont crank at all. However this time I check the battery and have full voltage and amperage is fine so i figure it must be the starter. Order a "new", rebuilt, starter and while removing the old one discover that the brass bushing at the end of the starter wheel that guides the wheel onto the flywheel is completely missing on the old one. So i figured that was another issue and put the new starter in and off i go.
A month later check my volt meter while driving discover i am only getting at most 13.1V from the alternator so i replace that with the assumption it is bad. keep driving and all seems good voltage while driving is between 13.5V and 14.2V.
Near the end of that season about a year ago now it develops a new symptom every once in a while the car when you sit in to start it you will turn the Key and NOTHING, not even a click from the starter.
Now for the odd part, I go to check the voltage at the battery and it shows 12.6V. when the key is turned to accesories or on everything in the car works fine. Figure it must be a dead cell in the battery so i get it jumped by a friend and it fires up fine and drives fine. Bring the car to my house pull the battery, test it with a load tester test just as good as a brand new battery.
SAID FUCK it put it away for the winter and took it out in the spring again this year and had NO ISSUES, until this week.
Get in the car after work turn the key and nothing. Accesories still work fine but nothing when trying to crank.
However, just now when a friend jumped it for me I tried to drive off and the Car began to BUCK LIKE A BASTARD, with the ABS light flashing came to a stop and all was fine, started driving again and BUCKED again, let it run for 25 minutes with me holding it at 2000 RPM to get the battery charged by the new alternator, shut it off and again NOTHING no crank.
Please someone help I am very quickly running out of ideas on where to go next to diagnose this vehicle
Thanks In Advance
-Car addict
-
Eeek. Seems like you have a bunch of problems there. I'd suspect you have a battery drain in the chassis. They're not fun to track down. I've heard that the E30 has a current limiting relay that will shut the whole car down if the battery voltage is too low.
First off, I'd remove, clean & resistance check all the vehicle grounds, especially the main grounding strap off the block at the motor mount and the fuse block grounds. If the car is dead, I'd also check for +12v at every one of those positive block studs on the firewall. If you have any odd readings, run a continuity check on the smaller wire running off the battery positive terminal. That's the DME main power line. I suspect it's the same as other E30...there is an inline fusible link in that wire, embedded under some shrink wrap, concealed under a plastic conduit/trunk protector.
Then I'd take a look for any other significant amp draw. Put an ammeter between the positive terminal of the battery and the primary positive wire. Turn the key to 'run' but don't try to start the car. Take a note of the amps. Should settle down to well under an amp; maybe 250mA or so. If it's higher, have a buddy watch the ammeter while you pull fuses one by one to see which circuit is causing the drain. If it's on the fused side of the chassis, you'll find it this way. The unfused side (starter, alternator, engine harness) is harder, since you should have the battery disconnected to test these components.
Do you have the electrical troubleshooting manual or a Bentley? Those are both worth their weight in gold trying to troubleshoot a starter problem.
-
Thank you very much Dave all very helpful I have another vehicle to get me around but should be able to start tracking down the issue this week/coming weekend
I have one from my one of my other e30's 1990 325i
which is the one for the 1991 e30 318is