84 stalling and subsequent hard start problem
05-29-2014 | 05:03 PM
#1
Thread Starter
Newbie
Joined: May 2014
Posts: 4
Likes: 0
From: South Milwaukee, WI
1984 500 SEL
84 stalling and subsequent hard start problem
Hello all, I'm new to the board. I just bought an 84 500 SEL that needed some minor work. Of the items, the alternator was first on the list. A little background: I purchased the car and was able to drive it home. It ran super good, drove great, but the alternator was not charging. I ended up installing a rebuilt alternator, and when I went to fire up the car, the OVP Relay fuse blew so the car wouldn't start. It took me at least 5 minutes to figure out the problem. New fuse and voila! Car fired right up, but wait a minute, something is funny here. It was idling at about 2000 RPM. After about 3 minutes or so, the car abruptly shut off.
I searched some forums, and most of the information pointed to the OVP relay being bad. I am currently awaiting the replacement, but in the mean time, to test I pulled the relay altogether. The car fired right up, idle stabilized to @ 600 rpm, but about 3 minutes into it, again it abruptly shut off. When you try re-starting it, it cranks over SUPER hard. Let it sit a few minutes and it will fire right back up, only to repeat.
Does this sound like its just the OVP or can someone steer me in a different direction? Like I said, the car ran perfect before this. It just seems like one heck of a coincidence.
Kris
I searched some forums, and most of the information pointed to the OVP relay being bad. I am currently awaiting the replacement, but in the mean time, to test I pulled the relay altogether. The car fired right up, idle stabilized to @ 600 rpm, but about 3 minutes into it, again it abruptly shut off. When you try re-starting it, it cranks over SUPER hard. Let it sit a few minutes and it will fire right back up, only to repeat.
Does this sound like its just the OVP or can someone steer me in a different direction? Like I said, the car ran perfect before this. It just seems like one heck of a coincidence.
Kris
06-19-2014 | 07:56 PM
#2
Thread Starter
Newbie
Joined: May 2014
Posts: 4
Likes: 0
From: South Milwaukee, WI
1984 500 SEL
Update: still looking for some help here, but many of my above answers are solved thanks to these forums. Thanks to all the contributors! I will do a write up on my troubleshooting process soon.
After getting the cold start high idle issue resolved, I have one more lingering item. I noticed before changing the IAC, ovp and speed controller that the car would stall after about 5 minutes or so (I was driving it with the IAC restricted). The temperature has consistently been between 60 and 80C when this happens. I was hoping fixing the hard start and idling issues would help but to no avail. When the car stalls, it is almost always in a similar time frame. After about 30 seconds or so the car will start right back up, and if it doesn't stall immediately, it will run fine until it cools off again. I am starting to wonder if it is an issue related to the 16c oil temperature changeover to lambda. Has anyone else seen this and if so, any suggestions what to look for?
After getting the cold start high idle issue resolved, I have one more lingering item. I noticed before changing the IAC, ovp and speed controller that the car would stall after about 5 minutes or so (I was driving it with the IAC restricted). The temperature has consistently been between 60 and 80C when this happens. I was hoping fixing the hard start and idling issues would help but to no avail. When the car stalls, it is almost always in a similar time frame. After about 30 seconds or so the car will start right back up, and if it doesn't stall immediately, it will run fine until it cools off again. I am starting to wonder if it is an issue related to the 16c oil temperature changeover to lambda. Has anyone else seen this and if so, any suggestions what to look for?
