Hello,

Recently acquired 1986 245 and have been doing some lighter maintenance to it so far. It had been a few days since I last started it. I replaced the air filter on Saturday and then the passenger tail light assembly on Sunday. After the tail light assembly change, I started up the car and it was fine but then stalled about 30 seconds after. I attempted to start it up again and it turned over but stalled about 10 seconds later. Then no start at all. I thought I might have done something inadvertently when replacing the air filter with the MAF connection. So, here's what I've done so far. Note: I replaced all of the fuses inside the car about a month ago.

1. Replaced 25 amp fuse near battery.
   1. The existing fuse was fine but wanted to change it.
      
2. Replaced air filter.
   • I actually had a difficult time taking off the air box cover. Not sure if I inadvertently damaged the connection to the MAF.
     
3. Replaced passenger side tail light assembly.
   • There are two black/ground wires, so I thought I mixed those up but I had it right initially.
     
   • I was able to start the car after replacing the tail light assembly but then it stalled after a few minutes. Then it would start and stall a few moments later and then no start at all (current state).
     

Here's what I've done so far after the stall and no start issues appeared.

1. Disconnected MAF to determine if it would start without it—did not.
   
2. Reconnected MAF—still no start.
   
3. Cleaned MAF sensor (with MAF sensor cleaner)—still no start.
   
4. Reseated air filter (I didn't install it correctly the first time—the cover was sitting higher than the entire air box)—still no start.
   
5. Checked the connections to the hall sensor.
   
6. Reverted back to the previous 25 amp fuse—still no start.
   
7. Replaced the fuel pump relay—still no start.
   • This was on my list to do anyways since the relay in there is over 20 year old.
     
8. Grounds look clean/okay as well (two near battery, one on the firewall, two near the injectors/fuel rail)
   
9. Checked the vacuum line for fuel on the fuel regulator—no fuel came out when I disconnected the vacuum line, so that's a good sign.

This morning after, doing number nine above, the car started without any issue and I let it idle for about 10–15 minutes. Did not stall as well. Weather conditions were in the lower 60s with lowering humidity as it just rained. Then this afternoon, temperatures were in the mid 70s and it doesn't turn over at all—just cranks. In some deeper research could this be the cold start valve/injector? Maybe something iffy with the 25 amp fuse connection near the battery?

Thank you!