Power, lack there of? (1 Viewer)

[concretejungle]

I know the 1fzfe is not exactly a speed demon, but i feel like she has lost a little power, after a tune up. About a month ago i replaced the spark plugs (denso iridium), spark plug wires, rotor and distributor cap with OEM from Cdan. I have M1 synthetic in the motor and diffs. Birfs have been serviced and greased with Amsoil. New belts and flushed the coolant. I checked the compression along the same time to find it within 2 psi across the board. After i replaced the plug wires and associated parts i really noticed an improved throttle response and more power. It was a seat-of-the-pants power increase because i never dynoed the truck. I did notice when replacing the wires that my spark plug seals may be leaking just a tad as there was slight amounts of oil on the plugs and wires as i removed the old ones.

I just got back from a 500+ round trip to the beach. On the way there and back it felt like the cruiser just didn't have the power it once did. There is a commercial out now showing cars driving along towing an anchor, that's the best way i could describe it. There were several times on the highway at cruising speed of 65mph that if i wanted to accelerate to 70 to make a pass it would take me flooring the pedal and 15 miles or so to do it . It just felt like a slug the entire trip. I can't seem to figure it out. When i changed the parts it was like a new truck, now, only a month or two later it seems like it is back to how it was before i changed the parts out.

Any suggestions?

 

[RavenTai]

did you have the AC on? takes quite a bit of life out of mine.

 

[concretejungle]

I did run the AC on the way back and partially on the way down. Damn slug, i'm going to have to get forced induction.

 

[Rich]

If it is running smooth but down on power a few possibilities are 1) restricted ariflow - airfilter, clogging catalytic converter, crunched exhaust pipe, or 2) restricted fuel flow - fuel filter, failing pump, failing pump relay. You should also verify proper ignition timing.

 

[concretejungle]

Thanks Rich, that's exactly what i was thinking. I have had two CELs stating insufficient catalytic converter, so perhaps they are on the way out. I was also thinking maybe the fuel filter since the rig has 165,000 miles and the original one on it. two good places to start. It runs very smooth though.

 

[bjowett]

Don't forget the heat and humidity! The whole east coast was brutally humid for a couple of weeks...

 

[hobbes]

If your engine is detecting knock (perhaps a combo of gas, more engine load due to a/c and fan clutch engaging, humidity, etc) the timing reduction could be what you are noticing. I've got light throttle knock and when I put in Techron Concentrate the truck felt noticably quicker. I'm not sure if the results are going to last once it runs out of the tank. I'm guessing I'd get the same peppier feel from 89 or 92 octane. Less knock = more timing = more power.

 

[concretejungle]

I have been running premium fuel because of a knock at a start. This trip i ran regular but put in a can of Seafoam. Brian, you may be right about the heat and humidity as a factor, it was wicked hot and about 90% humidity.

 

[Cruiserhead05]

Concrete, i know this is kind of an older thread but my 80 has been feeling exactly the same the last few weeks. i also noticed it on a trip to OBX last week. Soon, i am going to do plugs, wires, air filter and see if that doesnt help things. im hoping its just the weather though.....even at night i dont see a huge improvement, its humid as hell all the time here in VA.