Posted by Cliff Robb on January 19, 1999 at 13:51:21:
In Reply to: Re: '80 528i:Starting problem on damp/humid days w/ cold engine posted by Cliff Robb on January 19, 1999 at 13:46:02:
Forgot to mention your battery. Check the voltage drop when cranking. If it goes below 9.5V- time for a new battery. Or... maybe the alternator is tired & not charging adequately. Output voltage while running should be 13.5-14.5. Too high or low will toast the battery over time.
: Yeah, what Frank said. Plugs tired? Check for resistance & opens on your wires. Resistance should not be higher than 1k Ohms per inch. Original coil? Check resistance on the primary side. You should read 1 ohm or lower. The coil could have been replaced with a generic model for non-electronic ignition. They have higher primary resistance which will give you less spark. Since it does eventually run, the ignition box is probably ok. Obvoius to check the condition of the cap & rotor. A long shot would be too big of an air gap between the pick up coil & reluctor in the distributor. This would cause a weak spark signal to the ignition box. These things are pretty non-maintenance unless you suspect it's been tampered with. Good luck.
: : Car is nearly impossible to start on damp/humid days with a cold engine. Once started (if lucky) car runs very rough - must keep idle up with accelerator til warm. Engine runs fine then and will crank fine rest of day. Cold, dry days are no problem - car starts up immediately. Have replaced temp/time switch with upgrade to run cold start no matter what. Have bypassed the compensator solenoid. Not looking forward to spring. Any ideas?