Hesitation during thunderstorm...

[Jack]

So I was on the road last night near Atlanta during the thunderstorm.
Yes I know gasp, I drive my car like a car.
I was wondering if any one less has experienced hesitation during a heavy thunder storm?
I don't think it was the plug wells because of how quickly it resumed normal operation once the rain let up.
A few minutes.
My first guess was all that moisture getting pulled into the intake my next guess was moisture getting into the coil.
I'm still leaning toward intake st this point because I don't think the coil would be return to normal so quickly, but what do I know lol.

[thirdmanj]

So I was on the road last night near Atlanta during the thunderstorm.
Yes I know gasp, I drive my car like a car.
I was wondering if any one less has experienced hesitation during a heavy thunder storm?
I don't think it was the plug wells because of how quickly it resumed normal operation once the rain let up.
A few minutes.
My first guess was all that moisture getting pulled into the intake my next guess was moisture getting into the coil.
I'm still leaning toward intake st this point because I don't think the coil would be return to normal so quickly, but what do I know lol.

Something about lightning disturbs the circuits in the the Flux Capacitor. :p

In all seriousness though, what was your approximate proximity to the "action" of the storm? While its true lightning does affect the environment, I find it unlikely that it would mess with a car (even and 80s car's) electronics. But after all it is Lucas, so who knows what that devil magic is doing. My money is on it being a coincidence.

[Jack]

It had to be moisture related just has the How/Where.
It did fine as long as I kept it around 30rpms, 20rpms and it hesitated.
If I have it a lot of gas to accelerate it hesitated.
Whenever I came in the heavy rain, about 2-5minutes later the car returned to normal.
So I "know" it was "amount of moisture" related.

[thirdmanj]

It had to be moisture related just has the How/Where.
It did fine as long as I kept it around 30rpms, 20rpms and it hesitated.
If I have it a lot of gas to accelerate it hesitated.
Whenever I came in the heavy rain, about 2-5minutes later the car returned to normal.
So I "know" it was "amount of moisture" related.

Did you encounter rain, or are you talking about just a humidity increase? I hope someone with genuine expertise joins in soon. I do wish I was there, so I knew exactly what happened.

[Ron]

FWIW, contrary to popular belief, clean water is a VERY poor conductor...

[Jack]

Lol how many times do I have to say it was a heavy rain.
It was a blinding cats and dogs, tornado watch storm, trucks pulled over at underpasses, everyone has their flashers on.
Lol No offense but didn't expect the first step off this troubleshooting inquiry would be explaining what rain was.

[thirdmanj]

Lol how many times do I have to say it was a heavy rain.
It was a blinding cats and dogs, tornado watch storm, trucks pulled over at underpasses, everyone has their flashers on.
Lol No offense but didn't expect the first step off this troubleshooting inquiry would be explaining what rain was.

Doh! I just read "heavy thunderstorm" then I saw the rest of it. :hihi2: I've yet to drive 1258 in heavy rain, but that is something I've thought about. That engine compartment isn't very well enclosed.

[Michael]

A lot of water can enter the engine compartment, especially driving in heavy rain. The spray from the tires hits the Alternator...which is very low. Most newer cars have belly pans to protect the engine bay from standing water, ours do not. If that wasn't enough, the top of the engine is susceptible to water as well due to the vents and grills, so a very heavy rain could find its way into the bay.

With all that said, I would highly suspect that you were getting water in your intake. If it were around the suppressors, It would most likely not clear up as quick as you said. I doubt it would get around the coil(unless you don't have the cover), the coil is actually well protected. If you car is like most, the intake hose runs to the right side window vent...a lot of water can get in there during heavy rain. Unless you make a habit of driving in hard rain, I wouldn't bother modifying it, but you could easily route the intake hose pointing in a downward position and see if that solves your problem.

[Ron]

Just to give you a hard time:

...it resumed normal operation once the rain let up.


Whenever I came in the heavy rain, about 2-5minutes later the car returned to normal.

:confused:

=========

Since you mentioned it hesitating and not missing, I'd bet on water cooling one of the thermal switches off before moisture...

[Jack]

Sorry on iPhone. Was supposed to read when i came out of the heavy rain.
In other words, it was heavy really thick rain, then at points it let up, then back to heavy.
During the normal rain is when the engine returned to normal after 2-5 mins.

[WelmoedJ]

With my first D I noticed hesitation in heavy rain, but found that nr 6 had water into the spark plug recess.
A new cap solved that issue.

My current D never hesitated in heavy rain, though I had to decrese speed to below 50 Miles because my tires didn't like the rain gullys in the highway.

I also drive my car regardless the weather (except for when roads are iced).

[Dangermouse]

Lol how many times do I have to say it was a heavy rain.
It was a blinding cats and dogs, tornado watch storm, trucks pulled over at underpasses, everyone has their flashers on.
Lol No offense but didn't expect the first step off this troubleshooting inquiry would be explaining what rain was.

So, was it raining or not?

J/k. I was out in that storm last night in my DD and it was definitely throwing it down for a while. at times it was like someone just throwing a large bucket of water at the windscreen.

I would lean towards moisture laden air getting sucked in and making the filter damp, thus restricting airflow. Heat of the engine dries it out

If you were actually moving, then I would think it would be less likely that water would get to the top of the engine. But stopped in traffic, that I could definitely see.

[Exolis]

It is most likely due to extra water. Since the intake in Pontoon is a T-Shape, if there's enough water coming down, the vacuum can cause enough water to enter intake and will hinder performance.

Water splashing on the Alternator will not effect RPM, unless you have enough getting inside the alternator, however I would expect larger problems to come from this. So unlikely the issue unless your alternator is seizing up or not working.

[Ron]

Sorry on iPhone. Was supposed to read when i came out of the heavy rain.
In other words, it was heavy really thick rain, then at points it let up, then back to heavy.
During the normal rain is when the engine returned to normal after 2-5 mins.

;-)

It could also be water cooling off the CPR/WUR, O2 sensor, etc...

I just don't see it being ignition, A/F mixture polluted, etc, W/O it missing...

[Jack]

Thanks for the input everyone.
The first thing I'm going to check is rubber valve at the bottom of the intake port, inside the pontoon.
I bet it's clogged with leaves.. Causing it to fill with water.

[Bitsyncmaster]

;-)

It could also be water cooling off the CPR/WUR, O2 sensor, etc...

I just don't see it being ignition, A/F mixture polluted, etc, W/O it missing...

You beet me to it. I was going to suggest water got kicked up on the O2 sensor but I think that would make it go open loop so the mixture should richen.

[r00b]

I had a problem where the car would lose power. It would only happen when it was raining and I was on the freeway. Then the Engine died and wouldn't restart. I found the ignition coil wire wasn't off but was up enough from the distributor that it wouldn't work. I figured it was loose and water would hit it and move it enough to lose power. After pushing it back on, never had another problem.

[Ron]

You beet me to it. I was going to suggest water got kicked up on the O2 sensor but I think that would make it go open loop so the mixture should richen.
Agreed.
I'm thinking if water cooled off the ECT sensor (Lambda Thermal Switch), it would signal the ECU to go into open loop as well. And if the O2 sensor is cooled off, it would send false information to the ECU...If it cools it off enough, the ECU will recognize the signal as invalid/disconnected and go into open loop (assuming the D's ECU has a "standard level" of sophistication ;-).

[David T]

I would suspect bad ignition wires. When they got soaked with water you were losing spark. If they are old you might consider replacing them. Did you notice a lot of static on the radio (was it on?).
David Teitelbaum

[outatym2001]

I was wondering if any one less has experienced hesitation during a heavy thunder storm?
I don't think it was the plug wells because of how quickly it resumed normal operation once the rain let up.

I also experienced hesitation during a super-heavy downpour of rain. The hesitation/jerkiness would occur only when I pressed on the gas pedal more than half way down. The rain was so heavy it was causing streams of water to flow in the grooves worn into the concrete by all the tires. The problem went away as soon as the rain stopped and there have been no problems since then.
What was the reason for the hesitation? Heck if I know.
I currently don’t have a working radio as I am in the process of adding some amplifiers so I wasn’t able to listen for any static through the speakers.

[Starglider]

My guess would be all the water vapor cooling and partially quenching the flame front in the cylinders. Clearing up quickly doesn't rule out electrical because the water would evaporate off a hot engine quickly, but you'd expect outright misfire and not related to throttle setting if it was an ignition issue, not just loss of power.

[DeloreanJoshQ]

I can attest to experiencing the same issue yesterday while driving on the highway at 70 MPH.

When it started raining hard, I could hear an engine miss and feel a loss of power and as soon as the rain would lighten up, the engine would smooth out.
It would clear up rather quickly so I was thinking maybe water was getting into the air intake as well.

Also, at one point a bunch of water must have hit the alternator because the light came on and my gauge showed it was overcharging. However, after about 30 seconds the light went out and the gauge returned to normal.

And as always my oil light will go from dim to bright during rainy drives...

When all three symptoms happen at the same time, it is nerve-racking....I'd really like to figure out what exactly is causing the miss/hesitation and how to fix it.

Josh Q

[WelmoedJ]

I can attest to experiencing the same issue yesterday while driving on the highway at 70 MPH.

When it started raining hard, I could hear an engine miss and feel a loss of power and as soon as the rain would lighten up, the engine would smooth out.
It would clear up rather quickly so I was thinking maybe water was getting into the air intake as well.

Also, at one point a bunch of water must have hit the alternator because the light came on and my gauge showed it was overcharging. However, after about 30 seconds the light went out and the gauge returned to normal.

And as always my oil light will go from dim to bright during rainy drives...

When all three symptoms happen at the same time, it is nerve-racking....I'd really like to figure out what exactly is causing the miss/hesitation and how to fix it.

Josh Q

Although I only once experienced the partially loss of power during heavy rain I agree other symptoms like the oil light coming on as mentioned by you.
I also noticed every now and then the brake light doing the same.

My car came with a braided metal insulation on the high tension coil-to-distributor wire.
Once I removed that, the partially loss of power never occured again.
It may well be that old high tension and spark plug wires contribute to the partially loss of power in heavy rain.

[David T]

Although I only once experienced the partially loss of power during heavy rain I agree other symptoms like the oil light coming on as mentioned by you.
I also noticed every now and then the brake light doing the same.

My car came with a braided metal insulation on the high tension coil-to-distributor wire.
Once I removed that, the partially loss of power never occured again.
It may well be that old high tension and spark plug wires contribute to the partially loss of power in heavy rain.

I will take a stab at this. When the alternator belt got wet it slips causing the charging light to come on (tighten the belt or replace it). When the the wire going to the oil sender gets wet it grounds out because it is all crispy from the insulation getting burnt off (slide a heat resistant sleeve over it). Loss of power from the motor is because the ignition wires are old and shorting out. Maybe also the cap and rotor (replace with new). Three separate problems all caused by a single event, getting wet.
David Teitelbaum

[WelmoedJ]

I will take a stab at this. When the alternator belt got wet it slips causing the charging light to come on (tighten the belt or replace it). When the the wire going to the oil sender gets wet it grounds out because it is all crispy from the insulation getting burnt off (slide a heat resistant sleeve over it). Loss of power from the motor is because the ignition wires are old and shorting out. Maybe also the cap and rotor (replace with new). Three separate problems all caused by a single event, getting wet.
David Teitelbaum

I agree your arguments are valid.
But not in my case, as I have made changes, among others the ones you refer to.
My car has new ignition wires (that's why hesitation/power loss hasn't happened again), as well as the other parts you mention.

The oil sender wire has been replaces, including the sender itself, however in heavy rain the oil light does come on faintly, but not always.

A slipping belt indeed can cause the charging light to come on, but this hasn't happened to me.

The brake light coming on while in heavy rain may originate in the plug at the brake main cylinder which is pointed forward (to the front of the car) and get splashed.
I've cleaned the connector, wiring is still okay and I decided not to improve its insulation at the time.
I have seen this brake light a bit dim and only once while driving in a rain storm in Germany at 75 MpH, after I have changed the position by some 30 degrees.
So all measures seem to have helped.

[DeloreanJoshQ]

I have new cap rotor plugs and wires as well.
belt is tight but splash of water is plausible.
The location of oil lighter sender and lack of protection makes it vulnerable to grounding out during rain..

[David T]

If water gets into the alternator it could cause the brushes to not connect well to the slip rings causing the alternator to fail temporarily. It is in a low spot and if you are going through a lot of water it will get washed out well. Maybe even enough water to make a new, tight belt to slip for a moment.

Same for the oil sender. it is low on the motor and enough water could splash up to ground out the connector and make the light come on dimly. Put a rubber boot over it. That should fix that.

As for the brake light, if you are going through that much water that it is getting up to the plug on the reservoir, it is time to pull over to the side of the road and start swimming! Maybe water is also getting to the switch for the parking brake if you are driving in that much water.

When driving in those conditions I mention to my passenger it is time to go up to "Periscope Depth"! After driving in that kind of wet conditions it is a very good idea to regrease the front end and check the transmission fluid and motor oil for any evidence of water. Do not be surprised if a wheel bearing soon fails because the grease got washed out. A C/V joint too if there are any cracks or tears in a boot.
David Teitelbaum

[DMCMW Dave]

Think about where your alternator is (directly in line-of-splash from the right rear tire) compared to other cars, and that you are driving around in a car with holes in the engine cover and spark plug wells that point straight up.

[Farrar]

Think about where your alternator is (directly in line-of-splash from the right rear tire) compared to other cars

This reminds me... as I was removing a splash guard from one of the wheel arches of my DD to change the horn, I was wondering why the D has no splash guards. Were they not a common item in the 1970s/80s?