12 replies to this topic

[RealSlow]

So I've done a lot of reading, but I'm scratching my head on this. 1994 JDM SPI, runs fine 99% of the time, maybe a little rich, but no real issues.

However, when it's wet out, it will occasionally bog down and die at stops or when the revs drop. It will sputter and then stall. When this happens it will take multiple minutes before it will restart. There will be many times in that time span where it will crank, sputter, and then die. Usually once it has started acting up like this, it will die multiple more times until I can get it home.

I've recently used dielectric grease and wire dryer on the plug wires, spark plugs, and inside and outside the distributor cap. This worked through 2 days of rain, but then today the whole process started up again. I can hit massive standing water with no issues, but slowing for a stop, it dies.

I know the common culprit for all SPI issues is vacuum lines so I'll check them again, but the fact that it takes multiple minutes to start again, and only does it in the rain makes me think rain is getting into something and has to dry back out. Water in a vacuum line? Water in an O2 sensor? In the dry it's totally fine, no stalling or sputtering.

[68+86auto]

Replace the cap, rotor and leads with quality new ones. Where are you putting grease inside?

[bpirie1000]

With most water kicked up at arches i would suggest checking canisters in there for leaks or cracks.

Tried it when washing the car?

[sledgehammer]

Probably nothing to do with the problem -
 

just to eliminate it as a fault - loosen the fuel filler cap when it happens 
 

also check fuel filters for water / intermittent blocking

check clean fuel getting to injector & run some off to check for water / dirt

water can sit in a low part of a fuel line and take a while to creep towards the engine area

check the fuel pump sounds ok , check all pipes , fuel , vacuum pipes  & elbows as they can crack & not show up easily

check rotor arm isn't shorting to earth when warmed up

 

best of luck

Edited by sledgehammer, 03 May 2024 - 07:52 AM.

[RealSlow]

Replace the cap, rotor and leads with quality new ones. Where are you putting grease inside?

Leads were replaced 23,000km ago, rotor and cap were replaced 11,000km ago. I put grease along the lip of the cap where it joins to the body of the dizzy.

[RealSlow]

Probably nothing to do with the problem -
 

just to eliminate it as a fault - loosen the fuel filler cap when it happens 
 

also check fuel filters for water / intermittent blocking

check clean fuel getting to injector & run some off to check for water / dirt

water can sit in a low part of a fuel line and take a while to creep towards the engine area

check the fuel pump sounds ok , check all pipes , fuel , vacuum pipes  & elbows as they can crack & not show up easily

check rotor arm isn't shorting to earth when warmed up

 

best of luck

I know the fuel filter is original, and I'd wondered if somehow that could be the culprit. Wasn't sure why it would only act up in the wet though. But I guess it could be cracked and let water in. The fitting where it connects to the line running back to the fuel tank is pretty corroded, and I couldn't break it free to change it. Most likely going to have to change that whole line. I'll check the vacuum pipes again as well.

 

With most water kicked up at arches i would suggest checking canisters in there for leaks or cracks.

Tried it when washing the car?

What do you mean by cannisters in the arches? Haven't tried it while washing the car, that's a good idea.

[RealSlow]

 

Probably nothing to do with the problem -
 

just to eliminate it as a fault - loosen the fuel filler cap when it happens 
 

also check fuel filters for water / intermittent blocking

check clean fuel getting to injector & run some off to check for water / dirt

water can sit in a low part of a fuel line and take a while to creep towards the engine area

check the fuel pump sounds ok , check all pipes , fuel , vacuum pipes  & elbows as they can crack & not show up easily

check rotor arm isn't shorting to earth when warmed up

 

best of luck

I know the fuel filter is original, and I'd wondered if somehow that could be the culprit. Wasn't sure why it would only act up in the wet though. But I guess it could be cracked and let water in. The fitting where it connects to the line running back to the fuel tank is pretty corroded, and I couldn't break it free to change it. Most likely going to have to change that whole line. I'll check the vacuum pipes again as well.

 

With most water kicked up at arches i would suggest checking canisters in there for leaks or cracks.

Tried it when washing the car?

What do you mean by cannisters in the arches? Haven't tried it while washing the car, that's a good idea.

 

Doing some more reading, I'm guessing this is the charcoal cannister? I wasn't even aware this was a thing. I'll check that.

[bpirie1000]

Yip charcoal cannister. Also there was a duff batch of one way valves kicking about the replacement parts suppliers for, ages.

Such a pain to diagnose these spi's

[genpop]

https://usa.minispor...-cover-kit.html

 

Do you have the splash protection in front of the engine?

Edited by genpop, 03 May 2024 - 05:35 PM.

[RealSlow]

https://usa.minispor...-cover-kit.html

 

Do you have the splash protection in front of the engine?

I do not. 

[RealSlow]

Update: did some testing, and when I spray water into the ignition coil, I get sparks out of the boot on the ignition coil lead, that arca to another spark plug lead, and then the cars dies and won't restart.

I guess it is the spark plug leads. Dang, and those are (relatively) new. Time to order new ones. Would it be worth replacing the coil as well since that's where the sparking is coming from?

[68+86auto]

Update: did some testing, and when I spray water into the ignition coil, I get sparks out of the boot on the ignition coil lead, that arca to another spark plug lead, and then the cars dies and won't restart.

I guess it is the spark plug leads. Dang, and those are (relatively) new. Time to order new ones. Would it be worth replacing the coil as well since that's where the sparking is coming from?

It depends where exactly the arcing is from. The coil top could be cracked otherwise switching it is unnecessary. Some leads also don't create a good seal on some coils which can also cause issues.

Edited by 68+86auto, 05 May 2024 - 07:29 AM.

[pete l]

And change the fuel filter. I have an MG ZR from 2004, on it's original fuel filter. It decomposed inside and blocked up my injectors.