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Runs drives won't restart when warm


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92 loyale with 1.8 and 5 speed

Subie runs and drives. If you floor it in first gear it bogs down but idles just fines. After it warms up it drives ok but won't restart when warm. Will turn over start and die. Wait 10 minutes and it restarts. Replaced fuel pump fuel filter temp sensor plugs wires cap rotor camshaft sensor Been working on for 2 weeks and can't figure it out

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In other cars this can be a crank position sensor, or even a failing ignition coil. Starter can be affected by heat soak too in older Fords, but since it's cranking, that's unlikely. I'm leaning to a bad crank position sensor.

Edited by Bushwick
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Sounds like your exhaust is clogged......

 

If the cat was clogged, it'd be constant. Sounds like a heat soak issue (ignition coil) or if the car has a CPS, the CPS.

 

To rule out exhaust obstructions, a vacuum gauge with engine at idle will tell you right away. Could also unbolt the pipe at the header (before the cat) to rule out a melted honeycomb or collapsed muffler baffling.

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Before replacing items, it's always better to attach a multi-meter and get base readings.

 

 

 

Where is the coil mounted that gives charge to the spark plugs? Is it mounted ON the engine, or is it on an inner fender? IF it's directly attached to the engine via bracket, that can be a heat-soak issue where it works OK enough when engine is cold, but as it heats up, whatever is faulty can't cope. A simple temporary test would be mounting it on a cooler surface away from direct and indirect heat (like the exhaust manifold) and seeing if the engine runs longer or not (given coils can transmit lethal voltages, I don't suggest "testing" it yourself). Most are really inexpensive or at least they used to be and a junk yard version might be a good alternative to rule out yours.

 

 

Does this engine still have a carb? If so, that can be faulty. If it has an electric choke and it's stuck nearly shut, car will run as it should when cold, but will get starved for air when warmed up. Also, heavily worn components can screw with how much fuel is being dumped in.

 

Old cars could get vapor lock. Basically the fuel line gets TOO hot (common on cast iron engines with poor airflow over them) and the gasoline turns to vapor and the engine stalls. When the fuel line cools off, the vapor goes back to remaining liquid and the car restarts. Check for fuel lines near heat sources.

 

EDIT: NVM the carb stuff, MAF is fuel injected.

Edited by Bushwick
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Not many parts left that quit when hot then. Fuel pump could be suspect. Is it making any extra noises? i.e. can you hear whining now when before there was none? Fuel pressure regulator might be faulty. A really clogged fuel filter (like one with a ton of dirt in it) could choke the engine out, as would a heavily clogged air filter. Do you smell raw gas at all? EVAP systems can be issues in newer cars. Dunno how sensitive those earlier engines are. Most cars will still run though, albeit roughly.

 

I had  96' Mark VIII and it was around the 80k mile mark and a couple times it went from running fine, to not running and just cranking. Replaced the fuel cap and it went another 35k miles w/o issue. While never able to "prove" it was the cap, it seemed to be the issue in that case. I think I removed the cap when the car wouldn't start (it just cranked) and it fired right up so I replaced it and the problem never returned. Is this your issue? Probably not, but it takes 5 seconds to rule out by loosening the cap when it acts up. I ran that car everywhere, all year for nearly 4 more years after, and (it was in perfect mechanical condition having bought it with 60k miles and no rust) ran it to other states on many long distance runs. Ran like a top when sold too.

 

These are just guesses here, but things I'd go over with my own car if it was doing the same thing. 

Edited by Bushwick
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Ok,  back to the basics.  remove the timing covers and inspect timing belt marks.  Disconnect those round engine connectors clean thoroughly with electric cleaner.  Reconnect and push hard until you crossed.  Ziptie tightly.  Remove distributor and inspect drive gear in camshaft housing.  Disassemble distributor and clean with electrical cleaner.  Under the little plate moisture and dirt collects.  Blow gently with air. Inspect eps in distributor.  Inspect wires in distributor.  They like to get really dry and brittle where the go into distributor and at the connector.  Clean connector.  Make sure shaft is intact and that little screw has not come out and rotor is not just floating on shaft.  This is pretty common.  Set flywheel on the three timing marks on flywheel.  Dot should be straight up and the opposite straight down.  Rotate 180 degrees and just the opposite should occur.  Rotate engine to 1 TDC.  Reintall distributor.  Distributor when installed and adjusted should be set at 20 degrees.  The bolt should be somewhere in the middle of adjustment slide.

 

Try this and let us know,

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Cleaned distributer/ and disc. Starts and runs great. No stalls Still won't restart when warm. Drive 10 minutes. Turn it off. Still won't restart. Wait 5 min and cools down. Restarts. Checked connections. All are tight. Car runs and idles great. Just won't restart. Fuel pump is new and pressure is wnl. Could it fuel pressure reg. Or is more electrical Thanks for the help

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Did you try and remove the fuel cap yet? Or at the very least, loosen it? If the fuel system is under TOO much vacuum, it can cause an engine to stall. Caps have a breather on them that's spring activated and supposed to prevent that w/o letting fumes in the tank escape. If that's stuck in the closed position, as the fuel pump runs, it'll create a vacuum and the engine won't run. I'm near certain this is what caused the issue on my Mark VIII. The 1st time it happened, was same as you. It ran, shut it off. And 5 minutes later it wouldn't start. About 30 minutes after that it fired right up. 2nd time it occurred, same scenario. I removed the cap and it started right up. Thinking it was fluke, I still decided to leave it loose and it quit doing it, so bought a proper cap and it never happened again.

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Hopefully it's the issue as I'm betting your frustration with car and the small military you could have funded with all the parts you've already replaced has to be discouraging. Normally caps fail open, which is an emissions issue as it allows the fumes to escape rather than getting pulled through the charcoal canister and burned off. But they can also fail in the closed position which actually affects the engine being able to run. If you look closely at lawnmowers, weed wackers, chainsaws, etc. they typically have a small hole in the cap to allow air to get pulled. Old cars had the hole too, but once it was discovered the fumes were "bad", they put the springs in and made a flapper style valve.

 

I worked at an emissions place in my late teens (Ohio actually checks the caps ability to seal fumes as part of it's e-check) and we'd fail around 10% of the cars because their caps were faulty. When they fail OPEN, most aren't even aware.

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Most newer cars will throw a code when the gas cap fails open but rarely if ever throw a code if the gas cap fails closed.

 

What surprises me is this is a warm start issue on a fuel injected car and no one has thought to mention the engine coolant temperature sensor........

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How are you checking for spark?  At the plug wire, with a plug, or just an arc off the coil - distributor lead?

 

I had one that had a bad coil - distributor wire.  It would make a spark in air at the end of the coil lead, but would leak and lose the spark through the distributor, plug lead and plug.

 

What colour is  the spark?  Blue or orange?

 

Another possibility is a bad fuel pump relay.  These relays get flaky when old.  They will work for a while when cold, then open when warmed up.  But usually, it will fail when warmed up, and stop the car, but if the car is sitting in the sun when stopped, it will heat up and prevent the car from starting.   A/C and ventitalion keeps it cool enough to operate when driving.  Worth a look, anyway.  When it won't work, plug the green connectors together, turn on the igniiton and listen for the relay to click and the fuel pump to operate, on-off, about a 2 second interval.

 

Good luck.

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Checked fuel pressure 22 when running but goes to 10 when shut off.

 

22 lbs seems low to me but I would think whatever the fuel pressure is, it should not drop when the engine is shut off. If I am correct, what is causing the pressure drop? Problem may be as simple as the engine is being flooded when you shut it off. 

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Do EA82s have igniters like the EJ cars have. I had a 1977 Toyota that had an igniter. When it would get hot it would quit running and wouldn't start until it cooled off, It would still spark when it was hot but a very weak spark. Replaced the igniter and it never did it again.

 I forget what they call it but EAs have a little thing like a coil in the distributor.  Some kind of pick up coil. It could be that heating up and causing a bad spark situation.

 Also  kind of sounds like vapor lock.

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Plugged green connectors and here it clicking. Plugs wires distributer are new. It was a blue spark done with a screwdriver testing it. Considering driving it. Bought for my son from an older couple who spent some money redoing the engine. Could it be a gummed up fuel line

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