Can a loose Ignition coil cable cause power loss

[brainhax]

Hi there,
I had to tow my 80 Series home today. Right at the start of a small climb, it suddenly lost power (bogging down), and smoke started coming from under the bonnet—definitely from the airbox. The engine would still start, but when I tried to rev it using the accelerator cable in the engine bay, it would lose power when revved hard.
After towing it home, I had a closer look and found a loose cable connected to the ignition coil. I’ve reconnected it, and now I can rev it hard in neutral using either the accelerator pedal or the cable in the engine bay, and it idles well too.

Could a loose ignition coil cable have caused this issue? Just want to make sure before I go for test drive.

Thank you.

---
1997 , 1FZ-FE

 

[60 toy ota]

Really interesting, can you share more details?
Which cable was loose on the coil/ignitor (Low or high voltage)?
What year 80?
When it lost power was it misfiring or bogging down or...?
Check engine light?
Smoke in airbox as in exhaust or like a backfire started burning your filter or _____?

 

[brainhax]

Really interesting, can you share more details?
Which cable was loose on the coil/ignitor (Low or high voltage)?
What year 80?
When it lost power was it misfiring or bogging down or...?
Check engine light?
Smoke in airbox as in exhaust or like a backfire started burning your filter or _____?

Mine is 1997, 1FZ-FE and I am in Australia.
It was bogging down, I was pressing the gas but it wasn't moving forward.
There was no check engine light that I have seen at that time.
Just before it completly stopped, massive white smoke came out from under the bonut, exactly where the airbox is. Seems exaust smoke as air filter looked good upon checking.
I haven;t taken it to the road yet. Just want to make sure, else need to call tow truck again..

 

[petegangies]

I dont believe the ignition coil is on the same side of the engine as the airbox.. so it's interesting you've had smoke come from this area. If reconnecting the wire properly has solved your issue, then I would just keep an eye on things. You could scan the ecu (I assume your 97 has an OBD port) to check for any codes.. if no OBD port, then get a paper clip and jumper TE1 and E1 in the diagnostic port in the engine bay and count the flashes of the engine light on the dash for the code.

 

[Kernal]

"it suddenly lost power (bogging down), and smoke started coming from under the bonnet"

@brainhax :

Smoke or steam?
What did it smell like?
Coolant level normal?
Anything dripping on the ground or out the tailpipe?

 

[brainhax]

"it suddenly lost power (bogging down), and smoke started coming from under the bonnet"

@brainhax :

Smoke or steam?
What did it smell like?
Coolant level normal?
Anything dripping on the ground or out the tailpipe?

It's definitely smoke as it comes out of exhaust. I was at the driver seat when I saw the smoke and car started bogging down and stopped at the middle of an intersection.

Smoke came from air box , coil is on other side.

How about I try to reproduce the problem. Keep the car in neutral , rev it and then ask someone to pull the coil wire out. If same happens means it was the loose plug.

If the car revs & idle good, can I take a chance and drive it ?

 

[brainhax]

"it suddenly lost power (bogging down), and smoke started coming from under the bonnet"

@brainhax :

Smoke or steam?
What did it smell like?
Coolant level normal?
Anything dripping on the ground or out the tailpipe?

Still to check coolant level, nothing on the ground or out of tailpipe

 

[petegangies]

I wouldnt drive it, and I'd check the coolant as a priority, you could have had coolant dumped into the intake and it's steam you're seeing and not smoke. Steam can still come out the exhaust pipe. If it's smoke it could have backfired through the intake. I assume smoke was white and not black? Also pull your dipstick out and check the oil for any residue or smells.

 

[brainhax]

I wouldnt drive it, and I'd check the coolant as a priority, you could have had coolant dumped into the intake and it's steam you're seeing and not smoke. Steam can still come out the exhaust pipe. If it's smoke it could have backfired through the intake. I assume smoke was white and not black? Also pull your dipstick out and check the oil for any residue or smells.

I checked everything and went for a drive. All looked good. Exploded the exhaust in 3rd gear. It just lost power and I heard a big bang then it shut down.

 

[petegangies]

That’s proper exhaust detonation, not just a failed muffler.. the bang you heard point to unburnt fuel igniting in the exhaust after a severe misfire or a timing issue. The earlier bogging and loss of power fit that too, and the “white smoke” under the bonnet was likely exhaust/backfire gases rather than coolant. I wouldn’t drive it again until the root cause is sorted, otherwise you’ll just cause more damage. I’d be looking hard at ignition and timing control (coil, igniter, distributor, ECU/wiring) and also checking fuel delivery (FPR/injectors) for over-fuelling. The exhaust is the victim here, not the cause.

 

[Kernal]

Took a second or two for my brain to figure out what I was looking at, the muffler blew up (open)! (I think that's a first on this forum).

@brainhax : Already asked, can you tell us or describe, which wire was disconnected and reconnected to the coil or distributor?

Can you take a few photos of your engine, distributor position (where its bolted to the head), ?distributor/spark plug wire that was off, and anything that looks wrong??

Have you or anyone else been working on or around the engine recently for any reason??

 

[brainhax]

I don’t know why I believe the coil wire is the culprit. Today, after checking everything, I went for a test drive. I pushed it a bit on a dirt road, and on the way back home the muffler exploded. The engine was cranking but not starting after the incident, so I pushed the coil plug again and it started. I came home and cleaned the coil lead and socket, as shown in the pictures. It now starts, idles, and revs well. I can see water around the chassis near the muffler when it’s idling or revving, and it’s not fuel or oil. May be the coil wire connection went loose while driving so it happended?

 

[brainhax]

This is how it sounds:

 

[brainhax]

Took a second or two for my brain to figure out what I was looking at, the muffler blew up (open)! (I think that's a first on this forum).

@brainhax : Already asked, can you tell us or describe, which wire was disconnected and reconnected to the coil or distributor?

Can you take a few photos of your engine, distributor position (where its bolted to the head), ?distributor/spark plug wire that was off, and anything that looks wrong??

Have you or anyone else been working on or around the engine recently for any reason??

The wire that connects distributor to the coil was supper corroded at the ignition coil's end. It was not disconnected. As you can see in the pictures, so much gunk came out after cleaning it with Wd-40 today. This might be the cause of bogging down and stopping 2 days ago and exaust explod today. I don;t know why I feel I might have fixed the problem. Need to buy a new exaust though.

 

[petegangies]

your issues could definitely be related to your ignition system. I think I saw in another post that your car has 400,000+kms? Original ignition coil/leads? Has the timing been checked?

 

[brainhax]

your issues could definitely be related to your ignition system. I think I saw in another post that your car has 400,000+kms? Original ignition coil/leads? Has the timing been checked?

Yes, Its at 580,000KM & still orignal coil and leads. I haven't changed them. Timing has not been checked. Two days ago I topped up 20L Unleaded 91 Petrol just 2 minutes before the car started bogging down. Went back to the fuel station and they say the fuel has no issues...

 

[petegangies]

Yes, Its at 580,000KM & still orignal coil and leads. I haven't changed them. Timing has not been checked. Two days ago I topped up 20L Unleaded 91 Petrol just 2 minutes before the car started bogging down. Went back to the fuel station and they say the fuel has no issues...

it's plausible that your ignition system is tired and needs refreshing.

I know it's expensive (and you need them quickly), but I'd only run new genuine ignition leads, a new ignition coil, rotor and cap for the distributor.

Shop around as prices vary quite a lot.

It would also be worth checking your ignition timing if you have a timing light, or getting a mechanic to do it.

It would also be a good time to remove your existing spark plugs, observe their condition, check the gap and replace if necessary. Might also give you some additional clues.

 

[LongDuck]

Here's a theory; that Coil / Ignitor connector looks like someone ran a dull round file into it. A new Coil has a very clean and smooth connection point for the output lead. My theory is the connection was intermittent that allowed several,things to happen when it WASN'T sending impulse to fire the spark plug on to random cylinders; 1) it would allow unburned fuel to exit the cylinder(s) and enter the exhaust system, resulting in your muffler explosion, and 2) it would allow unburned fuel to be circulated during the intake stroke with some exiting the intake valve into the upper manifold resulting in any backfire causing an intake explosion.

These events would be exacerbated by problems with the Distributor (*timing?) but you said it otherwise ran well - when the Ignitor / Coil was working properly. The Cap and Rotor are cheap insurance, but at a minimum, I'd replace the Ignitor / Coil so you have good, solid connections. I'd also replace the leads for the same reason.

Just a theory, but unburned fuel vapor can cause all kinds of weird things both upstream and downstream of the engine combustion chambers.

Oh yeah - put in new spark plugs, too.

 

[brainhax]

Here's a theory; that Coil / Ignitor connector looks like someone ran a dull round file into it. A new Coil has a very clean and smooth connection point for the output lead. My theory is the connection was intermittent that allowed several,things to happen when it WASN'T sending impulse to fire the spark plug on to random cylinders; 1) it would allow unburned fuel to exit the cylinder(s) and enter the exhaust system, resulting in your muffler explosion, and 2) it would allow unburned fuel to be circulated during the intake stroke with some exiting the intake valve into the upper manifold resulting in any backfire causing an intake explosion.

These events would be exacerbated by problems with the Distributor (*timing?) but you said it otherwise ran well - when the Ignitor / Coil was working properly. The Cap and Rotor are cheap insurance, but at a minimum, I'd replace the Ignitor / Coil so you have good, solid connections. I'd also replace the leads for the same reason.

Just a theory, but unburned fuel vapor can cause all kinds of weird things both upstream and downstream of the engine combustion chambers.

Oh yeah - put in new spark plugs, too.

Yes that corrosion due to water crossings a year ago when the car bogged in water.. water made it's way to the coil and stayed there, I should have cleaned it properly after the trip. Today I used house vacuum cleaner and lot of cotton buds to clean that junk..

 

[Kernal]

Ditto; replace the coil, spark plug wires, spark plugs, air filter, --- and other preventive maintenance (PCV valve/hoses, etc) while while you're in there. FWIW IME Iridium type plugs (Denso Iridium TT for example) work well in the 1FZFE.

"I can see water around the chassis near the muffler when it’s idling or revving"

Did the muffler explosion damage the rear heater lines (is there coolant or just plain water in the cooling system??) or is that water from a recent water crossing?