Car shut down while driving.

[SWRT]

Sorry for the novel, guys.


Here's the scenario:

About two months ago I did an engine swap. This engine sounded great, ran great and not a bit of smoke or oil leaks so I bought it and took it home. I pulled off the valve covers and oil pan and sprayed the whole thing out with a gas/air mixture. I put on a new front main seal, rear main seal and cam seals. It got a new water pump, thermostat, timing belt, idler pulleys and valve cover gaskets. I ran some BG44k through it after it fired up to clean out any excess carbon and the engine was running awesome! I installed a manual oil pressure gauge to keep an eye on it since it was a new engine.

Well the other week the oil pressure gauge piping started to have a small leak due to having to move it once and reuse the compression fitting. I ended up trying to use black RTV around it to prevent it from leaking and that didnt work. It had kicked on the oil light, but I was watching the psi and it read fine and the oil light went back off. Well it happened again so I thought about buying new piping. One day it was on for about 30 seconds so I shut the car off and it went away. I ended up going up and buying new piping for it that day and when I went to change it out the new piping was crimped. Well I took that back and got another. It was crimped too so I just bought an entire new gauge. I installed the gauge yesterday. When I went to install it I had taken the alternator off and before I set it down I noticed I had forgot to disconnect the wiring on top or on the battery. It had been a long day with little sleep the night before so I started to take it off and I dropped the alternator on the radiator support and blew out the fusibile link. So I ended up making a new one with new fusible link wiring from autozone and it ran perfectly yesterday.


So today it had been running awesome all morning and I went to my girlfriend's house. Well it was time for church so we left. Now I know it's an old car that I just recently swapped the engine on so I got up to 40 and I sped up pretty slowly up to 50 when the sign changed speeds and the car started to feel a little laggy and went away so I drove a bit further to see if it'd do it again and four seconds later it started to feel laggy again so I start to slow down to pull over and the engine shut off while I was driving. I put it in neutral and coasted to a stop without power steering or braking. I shut the car down and looked under the alternator and found oil coming out of the gauge piping. I started the car back up and it was running rough as I was watching the oil pressure through the gauge (didnt get to see the RPM's) and it was shaking...feeling like it was missing or something so I shut it back off after about 5 seconds. I ended up putting the old oil plug back on there and connected the line again and started it up and it sounded find. Ran smooth. Idled smooth. I drove it back home about 10 miles to my parents house and it drove perfect the whole time. I watched the temp gauge the whole drive didnt move after it got up to running temperature. I checked the oil and no milk and I checked the coolant and no oil. All of the fluids on the car are at the proper level and everything to my knowledge is plugged in.


Could it have been the leak in the gauge piping? Not having that sensor hooked up?

Anyone have this happen before or have any ideas?

[Legacy777]

Did you have the stock oil pressure sensor/switch hooked up?

How much oil was coming out of the piping? Are we talking a lot or a little? I don't see how a leak in the piping would cause the engine to be "laggy".

Do you think your fusible link repair is good?

[SWRT]

Yeah, I just found it in my parts yesterday and hooked it back up.

Not much. Just a small leak. I guess it just happened around the same time so I'm not sure.

It wasn't great exactly. It was made with some fusible link from Napa and
using the old connectors since no one had any that were big enough. Going
to the junk yard tonight to see if I can find another one from a junk car to
see if it runs better. You think that may be part of the problem? It seemed
like it made a pretty good connection, but it's hard using old terminals.

[Legacy777]

Not sure.....but good rule of thumb is if you have problems after modifying/repairing something it's a good idea to double check that work.

[SWRT]

Well I just put the stock sensor back on. The engine ran fine up until a few days ago. I drove it to Georgia and back which was about a 7 hour trip and the first time the oil light kicked on was about an hour outside of Georgia and that's when I let it rest. It didnt flash on the way back.

I guess I'll just drive it around and see if the engine wants to cut out again. Hopefully after changing the fusible link and after reverting it back to stock it wont crap out again. I appreciate the help and I'll update you when I can. I'll probably drive it around a bit tomorrow.

[Legacy777]

Sounds good. Let us know what you find out.

[SWRT]

Will do. Planning on dropping the RS back off at my parents
and picking up the Legacy for some drive time tonight. Kind
of nice to drive the RS again though.

[SWRT]

Ok, so I drove it into work today, which is about 20-something miles from my house. No issues
with the engine Although the ball joint and outer tie rod end on the driver side are getting
replaced this weekend. The passenger will probably need it to, but it's gonna have to wait.

[SWRT]

Update:

So I was headed to my parents house to do the ball joint in the morning
and the car shut down again. Started it back up. Same issue. Sounded
like it was missing. Then I shut it off. 30 seconds later it starts up and
runs fine again. I dont get it.

Since then I've been letting it warm up before driving it and it hasn't
done it yet, but I'm not sure that was the problem.

Think I could have fried some wiring when I dropped that alternator?

[Legacy777]

It's kind of starting to sound like a MAF sensor issue.

What year and model Legacy do you have?

[SWRT]

I have a spare MAF so I could give it a shot. It's from a 97, but I'm pretty sure
they're the same thing. At least I know the one from my 90 worked in my 98 RS.

I have a 90 L. It's the AWD wagon version if that makes a difference.
Would it trip a code?

I remember when the MAF sensor was bad in the RS it ran like garbage.
It'd cut out on it's own, but only cause the rev's would rise and fall til it stalled.

[Legacy777]

I'm assuming that if the 90 MAF worked in the 98, your 90 L is AT and has the black JECS MAF. Assuming that, yes the 97 MAF "should" work. The newer MAF's may not have the added pins for "improper MAF sensor" check and may cause the ECU to throw a code 49 and not run right. Just give it a shot, and if you get a code 49 you can trick the ECU.

My MAF issue was very intermittent, I would lose power occasionally, revs would drop, and sometimes it would stall. It did not always leave a code, and seemed to be worse during the summer. I tracked this issue for over a year, and finally it acted up very bad, and left a code for the MAF confirming my suspicion

[SWRT]

I see. Then I'll definitely try this first then and hopefully that's the issue. It's
just weird cause it never gave me problems before.

It may also be a short in the alternator. If it's the same as the RS I'll throw
that on too.

My worst fear is that it messed up some wiring Trying to trace that...*sigh*
And I'm not good with wiring.

[SWRT]

So the spare MAF is an Autecs? Not a JECS. Also the code at the end is slightly different.

I'm pretty convinced that it's something electrical rather than the engine
itself though cause that thing ran freakin strong before I dropped that
alternator. It's still possible that it's the MAF though. Could have just been
really bad timing for it to go out. I'm gonna check the MAF on my RS tonight.
Haven't had the opportunity to look at it yet.

[Legacy777]

The autecs is likely the same MAF. Is it black and have a plastic body?

[SWRT]

Yep. Looks just like the other one.

Although I did see a metal one on a GL one time in the junk yard.
The inside looked like a spider web. Pretty awesome looking.

[SWRT]

So the MAF sensor isnt the problem. I put the other one on
and it ran the same.

I took my alternator up to Autozone and it passed all the
tests on the machine, but the dude showed me the bearing
wasnt doing too great. I never heard anything from it and
it never wobbled, but he spun it over and made a bit
of a squeal. I'm hoping that's the issue and I'm gonna
get another one today (hopefully $25 from the junk yard
if they have one) and give it a shot. If not I guess I'll just
have to buy one from Autozone for $120 Hoping that's
not the case.

[SWRT]

I found a spare alternator from a junk yard for $20 and took it up
to Autozone and it worked I threw it on my car last night and
drove in this morning and wow...it feels like I have my car back
again. Thanks for all of your help, man. I really appreciate the
input

[Legacy777]

Glad you got it figured out.

[SWRT]

Me too. It was stressing me out. Thanks again for all the help man. I really appreciate it!

[SWRT]

Yep...I guess it wasnt the alternator either. I mean it didnt do it for a few
weeks, but now it happened again yesterday. And I'm supposed to drive
this thing to Titusville for the launch on Friday and then Orlando that night.
I think I'm gonna try anyway.

[Legacy777]

You said you tried another MAF sensor correct? What car was that one from?

[H4_Deucer]

So the engine is from a 97 or just the MAF? If the engine is, I believe that was in the range where Subaru had problems with cam and crank sensors and they had a TSB for a reflash and to replace both sensors, those sensors would cause the issues that you are dealing with. I would think that it would throw a code but I have had some that don't.

[SWRT]

Yeah, I tried one from a 97 Legacy, but it felt exactly
the same.

The engine's from a 92 or 94. Cant really remember.
My neighbor suggested both of those actually. I have
a spare cam and crank sensor that I could throw on
this weekend. The crank sensor I believe has a really
long cable if I remember right so it'll be annoying, but
the cam sensor should just be one screw and a plug.

I'll give this a shot. Thanks!

[SWRT]

Ok, so it went away for a while and now it's back again. This is making me pretty aggravated.
Is it possible I burnt some wiring or messed up the ECU? I dont want to start throwing money
at it, but it needs fixed or I'm gonna junk it.

Lately it's started to hit a wall around 60mph. It'll drive decent, but once you get close to 60mph
it no longer wants to accelerate. It just stands there for a minute and sloooooooowly starts to climb.
It'll also have a slight backfire sometimes and it feels like it's running on less than all four cylinders
and the entire car will shake until I slow way down and try again.

Any ideas?