2000 - Spitting P0300 codes

[Captain Ali]

Hey you guys, this 2000 SE is spitting out these P0300 Multiple Engine Misfires codes, the car is running like crap and it won't move under it's own power.

New coil packs and wires less than 2k miles ago. It ran great ! Now all of a sudden it went belly up and runs like older cars did when the wires got wet.

I'm not that great with American cars I've had Volvos since the 90s sometime. So can you you point me in the right direction ?

Thanks,
Rich

[Captain Ali]

Do you think I may have water in my gas ?

We had a few consecutive days of very heavy downpours.

I took the car to get inspected it ran perfect on the way over like it always has.

Pulled into Herman's Repair to have it inspected, shut the car off. Gave the keys to Herman, he cranked it up and it immediately started running like crap.

I popped open the hood and found the boot between the air filter and the intake was half off so I reseated it and tightened it down.

Started it up, no change at all. Brand new wires and coils. it ran great up until the other day.

I took out the MAF sensor and douched it out with MAF Sensor cleaner/spray. No change.

No MAF sensor related codes, just the P0300 Multiple misfires. No other codes at all.

I checked the connectors to the ICM, they are correct and not damaged, frayed or show any sign of corrosion.



This has to be something simple I am overlooking.

[Captain Ali]

Also, I watched a YT video concerning a very rough running engine with multiple non cylinder related misfires. The guy says to tighten down on the 4 bolts that hold the fuse panel on the passenger side of the engine compartment. I'm going to do that next at least to eliminate the possibility of a grounding issue. I will report back with the results.

Thanks,
Rich

[Captain Ali]

I tightened down on the 3 grounding bolts in the engine compartment fuse panel. No change.

[Captain Ali]

Could the Crank Position Sensor be causing this ?

[Captain Ali]

Shouldn't the tach be bouncing when I crank it even though it won't start ?

The tach is not bouncing at all while it's being cranked over.
In Volvos this was an indication the Crank Position Sensor went bad.

Is this true with these Bonnevilles also ?

Rich

[Captain Ali]

From what I have gathered so far is what seems to be the point of failure is the Ignition Control Module.

I assume if the ICM is good I will get good spark from all 6 outputs from the coil packs.

Help !

[Captain Ali]

It was the ICM !