Car dies when hot, won't restart.

[NickD]

Hey guys! I'm having an ongoing problem with my '95 MX3. It's an RS, 1.6L DOHC with a manual. Early this year it started having some issues. One morning on the way to work after a heavy rain I was getting to work early. I decided to drop by McDs to get breakfast and when I pushed in the clutch to turn into their lot the car died. It started and ran just long enough to get into a spot, and then it was done. I sat in the car for 20 minutes or so, periodically trying to start it, and it finally restarted. I got to work (another 1/2 mile) and parked it for the day. After work it ran and I got home fine.

A few other times after that it would die at idle, but I could keep the rpms up and get where I needed to go. The symptoms would disappear leaving me with no way to trace it.

One day a month or so later I was going to do some side work and it started acting up. Then it just took a dump and was done. It would crank and crank but no fire. I'd recently picked up a spark checker and found I had no or little spark (none at all that day, I think).

side note: Luck would have it that 30 minutes later my wife's car puked the a/c compressor and I was stuck. Long of the short she ended up with a new car, I'm driving her old car, and the mx-3 is a backup car (that I don't trust).
/side note

I had the car's towed back to town. A few days later I took the mx-3 to a mechanic friend's and it ran fine to get there, then crapped out again. No spark. A month later he put a new distributor on it (couldn't find a used distributor as hard as he tried). It ran fine for him, and fine for me for awhile. I took it out on a joyride to try it out and after 20 or 30 minutes blasting around some country roads it was fine. Then three days later (with little driving) it did the same thing again. Drove it once since to take it to another mechanic friend's house. It misfired maybe once or twice, I think, but never crapped out. There it's sat for a week or so.

When it does crap out it's like the idle is dropping out and it bucks a little before dying. We checked the fuel pressure a few times, but it would never act up while the gauge was installed (drove it around a few days with the gauge on to watch it).

If anything is unclear, please ask for details. I'll give all I can. Sorry the post is so long, just trying to lay it all out there. I've searched until my fingers are blue but I've not found anything that sounds like what this car is doing. Actually, I did, but when I swapped out the distributor and nothing changed I was back to square one.

[Savin]

Check the timing, it could be off. That would cause it to misfire.
Check the plugs leading into the disty, the wires could be in bad shape. (mine sure were)
That new disty could have been defective....
Check your intake tube for cracks in the ribbed part. That would cause irratic idle and maybe cause the car to die...
If you have a spare $80 or so (probably less, depending on the current prices) Do the HEI mod. Its found in the V6 FAQ but it can also be done to the 4cyl with success.
Maybe new spark plugs and wires are in order?

My car sorta did the same thing long ago, but after replacing the head gasket, intake tube (mine was broken in half with duct tape holding it together), replacing the plugs leading into the disty (redid about 1ft worth of wire for each wire and put junkyard plugs on), rebuilt the disty(fully taking it apart and cleaning EVERYTHING, replaced cap/rotor too), The problem sorta disappeared. Car hasn't ran much since, so I don't know if the problem returned or not.

That's all I can help with.
Oh yeah, welcome to the boards! And from Indiana too! But southern IN?

[4gotn]

or your igntion could could be going bad....or water got in the cap and caused it to misfire...
those should be your only issues...

dont know why you would want to go hacking your car apart like he wants you to...

[Savin]

dont know why you would want to go hacking your car apart like he wants you to...

If that was in reference to me.... I didn't tell him to start hacking away anything. I said what I HAD to do to get mine to work. Mine was a similar case, so why not tell him? It doesn't mean he'll have to do the same things...
I just said to check stuff.

The only thing I suggested for him to personally do which involves "hacking" is the HEI mod. It doesn't mean he has to, it just suggested because when done right, it does nothing but good.

[SuperK]

NickD's, your mistake happened when you went to McD's.

Otherwise, how is your spark now with the new disty? Is it still low-no spark?

My car had a bad MAF/VAF. Sometimes when I let the car set, it would run like a champ. After a weekend of driving, it would start hesitating then refuse to start.

I would let it sit for a week or to and it would work like a champ for 3 more days tops.

If you disconnect the MAF/VAF when the car acts up, and nothing happens, then there's a problem.

You could disconnect the intake hosing completely and try starting it when it acts up... just remember to shut it off if it all of a sudden cranks up :S

Otherwise, do simple solutions. Spark plugs, wires... disty is new so meh. PCV valve definitely... and of course, vacuum leaks.

[NickD]

Lots of good leads, I'll have to start going down the list when I get a chance. Plenty of stuff to check before I try the ECU, which was my buddy's idea of the next step.

Check the timing, it could be off. That would cause it to misfire.
Check the plugs leading into the disty, the wires could be in bad shape. (mine sure were)
That new disty could have been defective....
Check your intake tube for cracks in the ribbed part. That would cause irratic idle and maybe cause the car to die...
If you have a spare $80 or so (probably less, depending on the current prices) Do the HEI mod. Its found in the V6 FAQ but it can also be done to the 4cyl with success.
Maybe new spark plugs and wires are in order?

My car sorta did the same thing long ago, but after replacing the head gasket, intake tube (mine was broken in half with duct tape holding it together), replacing the plugs leading into the disty (redid about 1ft worth of wire for each wire and put junkyard plugs on), rebuilt the disty(fully taking it apart and cleaning EVERYTHING, replaced cap/rotor too), The problem sorta disappeared. Car hasn't ran much since, so I don't know if the problem returned or not.

That's all I can help with.
Oh yeah, welcome to the boards! And from Indiana too! But southern IN?

I'm near Louisville, KY. Pretty much the other end of IN

I have checked for vacuum leaks as well as I could, but I'll do a quick check again for posterity's sake. All I can do is recheck everything to be sure, it's been a while since I could bring myself to look at the car. $250 for a distributor that didn't solve the problem left me a little sick of it for awhile.

NickD's, your mistake happened when you went to McD's.

Otherwise, how is your spark now with the new disty? Is it still low-no spark?

My car had a bad MAF/VAF. Sometimes when I let the car set, it would run like a champ. After a weekend of driving, it would start hesitating then refuse to start.

I would let it sit for a week or to and it would work like a champ for 3 more days tops.

If you disconnect the MAF/VAF when the car acts up, and nothing happens, then there's a problem.

You could disconnect the intake hosing completely and try starting it when it acts up... just remember to shut it off if it all of a sudden cranks up :S

Otherwise, do simple solutions. Spark plugs, wires... disty is new so meh. PCV valve definitely... and of course, vacuum leaks.

No kidding on the McD's. I usually try to avoid the place like the plague but those breakfast burritos are so irresistible sometimes .

I'll have to try pulling the intake and see what happens. I'll try anything at this point. Now I just need to get it to act up so I can try a few things.

[shameem]

As long as you are looking into things - Check the coolant temperature sensor - it is right by the thermostat. There are two coolant sensor - one is a two wire sensor that feeds the ECU (which needs to be checked/replaced) and the other is an one wire sender that goes to the temp gauge in the dash (you dont need to worry about that as long as the gauge works). They are both pretty much in the same general area below the disty.

[Ryan]

Easiest way to check for intake leaks is a propane torch (unlit) or something like brake/carb cleaner.

[Daninski]

If it bucks it's fuel for sure. Hows the filter? I've had a couple of cars buck and every time fuel. I owned a Ford Bronco, bucked all the time. Eventually I put it down.

[SuperK]

I know OldMan had a fuel issue and it was the strainer on the fuel pump.

Of course, there's a filter on the firewall, which is cheap and easy to replace.
Also the strainer on the fuel pump.

OldMan also had issues with the ECU. I have access to an ECU from a 94-95 manual RS if you need to go that route. It shouldn't be that expensive from the junkers.

His car wouldn't crank up when it warmed up... he carried a huge booster and sat there and cranked it for minutes before it'd start. ECU failure.

Let us know what you find out. Hope you can get your MX up and running again. She's a great car... when she's more than a storage bin.

[NickD]

As long as you are looking into things - Check the coolant temperature sensor - it is right by the thermostat. There are two coolant sensor - one is a two wire sensor that feeds the ECU (which needs to be checked/replaced) and the other is an one wire sender that goes to the temp gauge in the dash (you dont need to worry about that as long as the gauge works). They are both pretty much in the same general area below the disty.

Any way to test the coolant temp sensor? I know the gauge works, but what about the other sensor? If it's cheap enough I may replace it for good measure.

Easiest way to check for intake leaks is a propane torch (unlit) or something like brake/carb cleaner.

Been using starting fluid, I think.

If it bucks it's fuel for sure. Hows the filter? I've had a couple of cars buck and every time fuel. I owned a Ford Bronco, bucked all the time. Eventually I put it down.

Broncos are supposed to buck, right? I was told the filter was new less than 10,000 miles ago but I'll double check with the previous owner. Never checked the strainer, though. Can't hurt to pull it and check I suppose. Isn't it under the rear seat or something to that effect?

I know OldMan had a fuel issue and it was the strainer on the fuel pump.

Of course, there's a filter on the firewall, which is cheap and easy to replace.
Also the strainer on the fuel pump.

OldMan also had issues with the ECU. I have access to an ECU from a 94-95 manual RS if you need to go that route. It shouldn't be that expensive from the junkers.

His car wouldn't crank up when it warmed up... he carried a huge booster and sat there and cranked it for minutes before it'd start. ECU failure.

Let us know what you find out. Hope you can get your MX up and running again. She's a great car... when she's more than a storage bin.

I'll let you know if I need the ECU. They're hard to find here, that's for sure. Thanks for the offer!

[shameem]

http://www.mx-3.com/manuals/showimg.php ... F1-162.gif" onclick="window.open(this.href);return false;
Thew procedure is not very good at testing intermittent failures - the sensor only costs about 10-30 bucks depending on where you get it from..... If you can wait a few days - try http://rockauto.com" onclick="window.open(this.href);return false;

[NickD]

http://www.mx-3.com/manuals/showimg.php ... F1-162.gif
Thew procedure is not very good at testing intermittent failures - the sensor only costs about 10-30 bucks depending on where you get it from..... If you can wait a few days - try http://rockauto.com" onclick="window.open(this.href);return false;

Sweet! Hadn't found the manuals before.

[jt53]

probably your distributer mine did the exact same thing with two different distributors one of them being right out of the box, there known to be a problematic piece, There total junk I even have a reicpt from the previous owner who only had 50 000 kms on the one that died in the first place, some might say thats not bad but it was a 750$ install for that particular person, thats not cool.

[polaco]

i have same problem right now !!! first it started with idle goin up and down... and rest of the symptoms like yours are right now.... when its starts it works perfect... and some day wont just start or last time i had to push it from intersection... came back couple h later and it worked like never nothin happened.... i just find out from one mechanic that it could be a old catalytic converter... that supposed to be dirty... and when it gets hot it expands even more and shut down the car.... i gonna try disconnect the catalytic converter as soon car acts again.... i will update u on that ... unless u gonna do it before me... bc right now car drives good?...and thx for other posts too ! i tried most of them already but some have still to check!