Mysterious stall in traffic, hard to restart but then ok

Post by **JimBee** » 17 Dec 2021, 19:51

My usually reliable '93 854 winter driver had sat from May to December but then started right away and had no hiccuping problems until the other day. It started fine and I was a couple of miles from home in traffic when it just shut off. I was able to coast out of traffic and after several almost starts it finally fired up though roughly for a short while. After testing acceleration on a side road I completed my 10 mile round trip with no further issues.

Well, I'm happy that I got back but of course now I'm wondering. It quit just like I'd shut off the ignition. My first thought was the fuel pump. But when it restarted it behaved for a short while kind of like a flooded engine back in the days of carburetors.

Since it's back to normal there's really nothing to test.

Suggestions?

Oro · Post by **Oro** » 17 Dec 2021, 23:37

This is an entirely knew serious of automotive problems, called "Covid Cars."

"sat from May to December "

The amount of oxidation on connections is almost exponential when a car isn't fired up and heated up. Despite knowing all this stuff, I had to let an SUV of mine sit from 12/19 to 6/20 because of Covid and I'm still working out the damage ( new alternator tomorrow, despite a rebuilt one 4 years ago).

Do NOT start throwing parts at things like a fuel pump. Clean things like alternator, starter, battery grounds and leads. Clean things, connections, and likely it's not something expensive.

Do a bunch of short trips with it to heat things up, burn off oxidation, build confidence in it.

I'm not shocked about this re: Covid as for 20 years I've picked up a lot of motorcycles that where either running, sitting, sitting 4 years, sitting 6 years, etc. and learned how time affected different systems and interrupted the normal system.

"Covid Cars" are now a thing like "Covid Dogs" (my parents adopted one this fall - oh what a project), and very sadly, "Covid Kids."

Work it through from a neglected electrical perspective and not throw money and parts at it off the top.

Post by **JimBee** » 18 Dec 2021, 09:57

Thanks, Oro,

That's an interesting and somewhat comforting perspective. Given the low voltage and amperage of many things in the ignition pathway, your theory makes sense. Actually most of my trips in winter are fairly short range, 6, 8, 15 miles RT, so it wouldn't be hard to get it home if I got stuck.

I have another summer driver so the '93 usually sits for 5 or 6 months of the year, haven't had this happen before. Hopefully, just a freak occurrence!

Post by **scot850** » 18 Dec 2021, 16:01

I had to work out a few bugs on my car this year due to is sitting a lot over the last 2 years. Electrical issues were the biggest problems. I also agree with the cleaning the electrical connections. The 93 is nearly 30 years old now so a few gremlins are likely.

I would check the obvious: Battery (how old is it and have it tested) and battery connections are clean, ground cables are all clean. Remove the distributor cap and clean the cap contacts and the rotor arm contacts. While in there check the cam seal hasn't failed and filled the distributor with oil.

Then the simple stuff like how old is the gasoline? Have you filled it with fresh gasoline? Could be you had water in the last tank fill up or the gas has gone bad.

Then start working through the other electrical connections like cam sensors and ECT (water temo sensor and connector at the back of the power steering pump).

Good luck!

Neil.

Post by **matthew1** » 18 Dec 2021, 16:58

scot850 wrote: ↑18 Dec 2021, 16:01
Then the simple stuff like how old is the gasoline? Have you filled it with fresh gasoline? Could be you had water in the last tank fill up or the gas has gone bad.

+1. This was my first thought. Was this the same fuel that sat for months? Did you put fuel stabilizer in while it was sitting?

Post by **erikv11** » 18 Dec 2021, 18:31

The symptoms are similar to when I somehow let the cap and rotor contacts get very bad on my seldom-used, beater 96 NA. Last summer when I started using it again it would run fine for a while then shut down, usually in the middle of an intersection coming off a red light or stop sign. Hard to restart, then worked fine around town once I got it going. Never got it on the highway etc, just a town car. Finally quit in an intersection one day. When I pulled the cap it was completely crudded up with deposits. Maybe related to Oro's comments, now that I read them. Swap in a different cap and rotor from the parts pile and all is well.

Anyway, I'd take a look under the cap, too.

Post by **rguzz** » 18 Dec 2021, 20:49

Check fuel pressure anyway. Anytime I hear stalled, dropped out then ran fine again I worry about what will really leave me stranded and that's no fuel.

Post by **JimBee** » 18 Dec 2021, 21:00

Another theory that I'd like not to think about but is a possibility. rguzz points to the fuel system, which of course, includes the fuel pressure regulator. I've never installed a new one in this car. I have a used one in inventory, hope it's not that

Post by **JimBee** » 18 Dec 2021, 21:04

I haven't commented on MVS site for a while. I wrote out a fairly lengthy reply to the other posters, grateful for their input with a list of things that I think I have pretty well covered and appreciative of the feedback.

It didn't post. In the past, I've used "edit" a lot for afterthoughts but I'm not seeing that option, either.

Matt: Am I missing something?

Post by **matthew1** » 19 Dec 2021, 09:55

Jim, I'm sorry the site ate your post. I don't know of anything on this side of it that would have caused that.

Editing is alive and well. Click the three dots and it's in there. If you're on a larger desktop computer, it'll be the pencil icon in the same spot.

: edit.jpg (24.44 KiB) Viewed 743 times