It's the only issue I've never been able to solve with this car. It rains, car goes :toilet: It idles roughly and stalls at lights. It did this before the rebuild and still does it now. I mean rebuilt engine, new carburetor, new fuel pump, new HEI distributor which I've already changed the cap on twice trying to put a stop to this. Wires are MSD. What logical reason could be left for this to happen between old and new parts? I've also tried putting water dryer in the gas tank. No effect. And actually the weather conditions have to be pretty specific for this to happen. Has to be cool but not really freezing. LIGHT rain or snow(I've had the car out in monsoons with no trouble). Basically cool and humid. And here's the other thing: more than once while this is happening I've stopped at a light and the car is idling like a mechanical bull and then suddenly, like someone flipped a switch, it stops and smooths out. And you know my boss who has a 94 3.8 Mustang just told me that it used to to do that too before his engine rebuild. Anybody have ANY far out theory as to why this happens?
My old '90 2.3L Mustang ran like total dog doo in the rain for the last couple years I had it, I never did figure it out. I had a hunch it was the TFI going out but I never got around to trying another one before I got rid of the car.
Change you're ignition coil?
Happened to me as well one time, i treid many things but it was probably icing. once the engine got some heat it ran fine and ever since
Well the distributor came with a new coil, I haven't replaced it since then. I've replaced its cover though. I'm not sure how moisture could affect it.
wow, that’s strange. My first thought would be something getting wet.
“cool but not really freezing “ (Ice sealing the leak)
But
“(I've had the car out in monsoons with no trouble)”
kind of rules that out.
“like someone flipped a switch, it stops and smooths out”
the drop of water shorting something out got shaken off?
I think I would suggest looking at what in the operation of the motor hasn’t been replaced?
For a motor to run requires Air, Fuel, and spark.
AIR I would think could be ruled out as the only thing between the motor and the atmosphere is an air filter and I can’t see there being any sudden change (“flipped a switch”) to an air filter. Unless it’s in bad repair and has a tear or something?
FUEL, Filter, lines, ?
SPARK. Coil, Something shorting.. but why not in a monsoon?
Got me man.. hopefully my thought’s here can trigger somebody else
Well I currently have a K&N filter and it's in good repair. Regardless I was using a paper filter when this started happening. Fuel filter has been replaced numerous times and with varying styles as I've continued modifying the car, I think I can rule it out. I haven't really touched the lines back of the fuel pump. Maybe I can check that. As far as spark goes, the HEI is a self-contained system except for the relay that turns it on. The relay routes power direct from the battery and is triggered by the factory coil wire. Could there be enough of a fluctuation in the factory harness to screw up a relay that bad?
Granted my harness was pretty hacked before I owned the car (I think the last owner knew just enough about cars to be dangerous). One of these weekends maybe I should weed out the dead connections and run new wire, atleast within the engine bay.
Little update. Turns out the car IS affected by heavy rain, atleast if I'm moving fast enough. I drove from Lethbridge to Medicine Hat yesterday in a rain/snow april blizzard thing and by the end of the trip the car was struggling to maintain speed and shuddering if I dropped below 100 kph. When I pulled over to the side to check things it stalled. It started to run right again once I got into town, probably because there wasn't a constant stream of water blowing through the grill. Was still rough when I got to the hotel, and the exhaust was turning the ground black. That says to me unburnt fuel and that points at weak spark. Electrical it is then I suppose. Though it's still weird. The ignition system is almost completely separate from the harness except for the one relay. How could that one relay go so screwy and there not be some other weird electrical gremlins? Radio, wipers, lights all tend to work fine. I replaced the engine ground strap a while back....
Look under the hood in the dark and see if there are any sparks jumping around.
Get a spray bottle (Windex bottle) and spray water on the various components and see if you can find the touchy one.
I've tried the spray bottle thing before with no result. I can always try again I suppose. Another weird thing just occurred to me. The car doesn't go straight to stall when I start it. It starts up. After a minute or two I kick it off the fast idle. It'll idle for a bit after that and get progressively worse until it finally stalls. The interval can be up to like 5 minutes or more. If the problem was electrical wouldn't it be evident right off the bat?
Distributor stator? Mine would fail after the engine heated up and then the car wouldn't start again for up to 45 minutes (basically until it cooled down again)
Not sure what a stator is but keep in mind I have a GM style distributor.
Boy this is turning out to be the business trip from hell. I tried to drive from Medicine Hat home to Calgary (it's still raining). Within an hour the car was having trouble maintaining speed, it would shudder if I didn't massage the peddle just right. Eventually speed dropped to 70 kph and I couldn't get it back up even with the peddle floored. Went like that maybe 5 minutes and the speed was dropping slowly but surely until it finally stalled as I was pulling to the side of the road. I almost whipped out the old AMA card but I decided to spray some WD40 here and there and then I gave it 5 minutes for some heat to build up under the hood. Sure enough it roared to life again and ran like nothing happened. Atleast for the 10 minutes it took me to get to the next town and for another 20 minutes or so while I found a hotel to wait out the storm. It was still idling smooth when I shut it down. Now I only sprayed the WD40 on that wiring panel on the firewall (car's left), the alternator connections, and the starter relay. If I had the means right now I'd take some pictures to show you but off the bat, any tips for sealing up those areas? I don't consider WD40 a solution.
i had that same problem, its related to the EGR vavle and the TPI along with the thermostat.
see i had the same problem, starts, calms down, dead. i have a switch under my dash that turns on and off the thermostat. (it was a fix with what i had in the garage and i needed to get to work) if i turned power off tot he thermostat, it'd crank up just like it was warm. now this isnt something good, its not a good idea, but it works for a short time till you can replace the thermostat and EGR. im pretty much sure its the thermostat and egr compounded. after replacing that and the tpi i havnt had the problem. btw, you can also try by tweaking the tpi to keep the car idling up near 850 rpm and you wont have the car dieing, but you might run into the car wanting to go UP HILL from a dead stop with no gas...
I don't know....it sure sounds like the stator problem I had. A stator is an electronic part inside the distributor. It's part of the mechanism that senses crankshaft position so the computer knows when to apply fuel and/or spark (it is NOT the TFI module on the outside of the distributor). I don't know if the stator is physically separate from the hall effect sensor or not, someone else here would have to answer that. I had the same issues with massaging the pedal, thought it was my transmission, but really the computer wasn't sending fuel and/or spark because the stator was cutting out and the computer was thinking that the crankshaft wasn't turning. When you let the car sit, heat drains away from the distributor and in my case that was what let the car run again after a while -- the stator had cooled. I had replaced everything else in the ignition system before a friend had suggested the stator to me, and that turned out to be it.
;) I think you guys are both thinking my car is fuel injected. It's not. Doesn't have an EGR and the computer has nothing to do with the ignition.
ah well, i guess i underestimated the 4 eyes... thats usually what causes those symptoms on my 87..
hell if it's not so complicated, just make sure everything that seals, SEALS. i doubt its the dist and such, like i said the stuff that makes my car do what your's is, is a vaccume leak... so if its high humidity that causes the car not to run right, and i suspect carburation? possibly your timing isnt perfect... i mean it runs GOOD on nice days? well from what i've learned, height from sea level, humidity, etc, on a full out motor is KEY to making the car run right. next time its at that special moment where it'll start and die, mess around with the timing and such. i mean you got a pretty badass setup, it kinda makes sense that the thing is finniky...
Let's assume for a minute it is not electrical. Then we have to wonder if the fuel/air ratio is correct for the temperature of the engine.
I had a 61 Ford Anglia that was a great little warm weather car. But in the winter, especially when I had it up in NY State for a couple of winters, it was a dog. At 0 degrees F it would not start. Running at highway speed between 0 and 25 degrees it would cool down so much I would have to pull the choke out (manual choke) to keep it running.
I think either too rich or too lean could cause your problem.
Do you have a hot enough thermostat and is it working?
Have you looked at the choke when it stalls? open, closed, in between?
I believe your original choke was heated by warm air piped through the exhaust manifold. Some chokes are warmed by an electric heater powered by the stator voltage from the alternator.
I don't know what your choke situation is.
Your original air cleaner had a temperature controled door to let in either outside air or air warmed by the exhaust manifold.
There is usualy some method of warming the under side of the carb.
Like exhaust gas routed through a chamber in the intake manifold under the carb. This would be controlled by a valve to shut off the exhaust gas when the engine is hot enough.
You may have had an EGR spacer under the carb with engine coolent running through it. Not sure if that is to cool the exhaust gas or warm the carb. Maybe both.
Just a lot of rambling thoughts.
Well granted the car was running much cooler than normal out on the highway. There's no thermostat in the dash but the one in my rad cap read only 60 degrees. Normally reads 180 and I tend to assume the engine's thermostat had closed since it's rated for 192 so I don't really know what the temp was. Currently there's no means for temp control in my engine, and the choke is a Holley electric version. But I tend to think temp isn't really the deciding factor because I finnished the drive home today and it wasn't any warmer but it had finally stopped raining and the car had no trouble.
The last time I saw a temp. gauge in the radiator cap was on a 20's vintage car with the cap at the front of the hood with a thermometer built into it. You could look at it through the windshield.
Maybe you should consider installing a temp. gauge sensor in the intake manifold.
The thermostat and the radiator are the temp. control.
I would think water evaporating off the radiator and other engine parts would drive the temp. down farther than air alone.
But you are right, it probably is electrical, this is just something else to keep in the back of your mind.
I bought that rad cap in a performance shop one day when I felt like blowing some money. There is a temp sensor in the manifold but it just connects to an idiot light in the dash. Actually pretty much every sensor just leads to the same check engine light. Probably saved Ford some money at the time. When I said there's no temp control I meant for the carburetor itself. The warm air intake system isn't connected, it never seemed to make a difference, not to mention it stayed on way more than I thought it should. There's an old connector in the harness that my coil wire routes through, that's the wire I use to trigger my HEI ignition. I'm gonna try taping that up or something and see if that's it.
Yeah, my 84 has the red "Engine Light" which indicates the coolent is too hot or the oil pressure is too low. Take your pick.
No way to know if its running too cool.
you said that it was chugging black smoke the last time it acted up?
If I understand you right the choke coil isn't hooked up. If you have a holley you can put an electric choke on easily. sounds like your choke plate is closing and making your motor pig rich.
louie