More Northstar trouble

[Mikel]

For today's edition of "what's wrong with my Northstar engine"... 2000 Eldorado. I powerwashed the engine compartment and now the engine has a severe miss and drives as if on four cylinders. Scanner shows a P0300 misfire. (there was a prior EVAP system error I never fixed). Any ideas? Thank you.

 

[Lumberjack]

"power washed engine bay" Let it dry for a few days and reset codes. Coil or plug wire has moisture in it. If that doesn't delay the inevitable, may need to swap coils and or wires until you find culprit. I had an 01 Tahoe that did same thing after engine wash.

 

[Gdogg]

If you power washed it pull all the coils, dry everything and probably replace the boots. Also use some di-electric grease.
My buddy spent 35 years in the Dyno Lab at GM, you should hear some of his stories about this engine.

 

[JR4X]

If you power washed it pull all the coils, dry everything and probably replace the boots. Also use some di-electric grease.

That was what I was going to suggest. BTDT

 

[arse_sidewards]

you should hear some of his stories about this engine.

 

[JohnnyJ]

pack it in rice?

 

[Thatg9659]

I power washed a Volvo engine compartment recently, had to pull the cover and suck the oil water mess out of the plug wells.

I Always do it with the engine running but it stalled before I was done.

 

[arse_sidewards]

I power washed a Volvo engine compartment recently, had to pull the cover and suck the oil water mess out of the plug wells.

I Always do it with the engine running but it stalled before I was done.

Next time fire up the leaf blower and blast that shit away.

 

[Thatg9659]

Next time fire up the leaf blower and blast that shit away.

So I can wash it again?

 

[arse_sidewards]

So I can wash it again?

Or just wash the engine bay first and the rest of the car second.

 

[Mikel]

Thank you guys. Will pull the coil packs and dry everything.

 

[Thatg9659]

Or just wash the engine bay first and the rest of the car second.

Sucking the oilwater mess out with the shop vac seemed better than blasting it everywhere because it usually ends up on me.

 

[JohnnyJ]

At least you know the starter isn't soaked.

 

[Mikel]

It's been a very hot week with a few hundred miles of driving and it hasn't changed (engine shakes and idles/runs as if it's running on half the cylinders). Here is the live data with the engine idling (warm). All I get is a P0300 misfire code (there are some EVAP errors that have been there for a long time but caused no driveability issues). Any suggestions? Thanks.

 

[WyoJeeper]

Start unplugging coils and see if it changes. My 2004 Caddy SLS did the same. I swapped coils around to figure out which was bad.

 

[BigBurt]

If you power washed it pull all the coils, dry everything and probably replace the boots. Also use some di-electric grease.
My buddy spent 35 years in the Dyno Lab at GM, you should hear some of his stories about this engine.

Well way to leave us hanging

 

[Mikel]

Start unplugging coils and see if it changes. My 2004 Caddy SLS did the same. I swapped coils around to figure out which was bad.

The problem is that these coils come in cassettes of four, one per bank.

I assume I can check the resistance of the primary and secondary coils to test them?

Thanks.

 

[Zg86]

Looking at the fuel trims its obvious the bank 1 coil is bad

 

[WyoJeeper]

Those are the PITA coils packs. DO they have the individual coil connectors on the rail?

 

[Mikel]

Looking at the fuel trims its obvious the bank 1 coil is bad

How can you tell?

I did unplug the front and rear coil sets and one did make a bigger difference than the other. Ordered a replacement.
Thanks.

 

[Mikel]

Those are the PITA coils packs. DO they have the individual coil connectors on the rail?

No, just two big connectors (front and rear).

Thanks.

 

[Zg86]

Look at the bank 1 short term fuel at -99% It isnt burning it.

 

[Mikel]

Look at the bank 1 short term fuel at -99% It isnt burning it.

Thanks. I started watching videos on fuel trims.

 

[Mikel]

Look at the bank 1 short term fuel at -99% It isnt burning it.

The (-) looks like dirt on the screen (there are examples of how the screen displays (-) and it does not look like that. If the 99% is positive, wouldn't that point towards a non working injector, with the computer trying to add fuel?

Thanks.

 

[xr-nut]

<-------- guy who cleans a LOT of cars every year. Well, not me, I have people. Most vehicles get strict DO NOT BLOW WATER AT THE ENGINE. Fords especially.

 

[Mikel]

It was two coils. I sprayed water into the exhaust manifolds and two cylinders were dead. Injectors checked out OK and were getting power, so I got a set of junkyard coils and it's working well now.

Thank you all.