P0300, P0301 and P0306 with relay cycling. Fuel pump fail possibility.

aa010175

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Help needed please. Last year I did a head job at 250,000 miles. Replaced almost all parts that should be renewed. The other day I started up the car and I heard a relay cycling back forth under the dash or hood. I started the car and it would barely run because it was missing so bad. Tripped a p0300, p0301 and a p0306. I now have a thumping sound come from the left rear when the power is turned on. I have never heard that before. The tank is 1/2 full. Could it be a fuel pump starting to stumble? It has very little power going up a hill. I also pulled the EFI and 20A EFI fuse and the thumping did not stop.
 
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Help needed please. Last year I did a head job at 250,000 miles. Replaced almost all parts that should be renewed. The other day I started up the car and I heard a relay cycling back forth under the dash or hood. I started the car and it would barely run because it was missing so bad. Tripped a p0300, p0301 and a p0306. I now have a thumping sound come from the left rear when the power is turned on. I have never heard that before. The tank is 1/2 full. Could it be a fuel pump starting to stumble? It has very little power going up a hill. I also pulled the EFI and 20A EFI fuse and the thumping did not stop.

What year is your 4Runner?
How many miles do you have now?
What other work have you done on it recently?
 
It’s a 2000 V-6. Update on my problem. The thumping was the rear wiper motor running. I Reset the check engine light. This time only P0301 tripped. Pulled the number 1 plug and found it to be badly beat up. No compression in number one plug. I’m in the process of pull the head that was rebuilt 12 months ago. I think one valve failed.
 
It’s a 2000 V-6. Update on my problem. The thumping was the rear wiper motor running. I Reset the check engine light. This time only P0301 tripped. Pulled the number 1 plug and found it to be badly beat up. No compression in number one plug. I’m in the process of pull the head that was rebuilt 12 months ago. I think one valve failed.


We’re you driving it with the check engine light flashing?


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I think u are on the right track. I don’t like the sound of the spark plug being messed up. That may entail a piston, spark plug and valve replacement. Hopefully just a spark plug and valve. I am interested in what you find in cylinder 6 if anything.
 

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