*HELP* Issues After K&N Install

Preface: 2000 Toyota Tacoma 3.4L 4x4 252800 miles - Excellent condition motor and tranny verified by two separate licensed and reputable shops


I recently (as in yesterday) installed a brand new, to spec, K&N Air Intake system. I have worked on my own cars before for minor work like this before and am very good at sticking to directions. I followed the directions to the 'T'. After final install and everything bolted down tight, the issue is underpowered acceleration. I tested this. I switched back to the original air box + filter. Truck ran just fine with no issues. Put the K&N back on, and same old sluggish, juttering at times (almost like little to no fuel) when pushing pedal near to the floor. Even if I take it easy on the throttle, it still feels underpowered. What gives, K&N?! YOU WERE SUPPOSED TO ADD MORE POWER, NOT DETRACT FROM IT!! (+10 awesome points if you get the reference)

Anyways. I checked, re-checked, and checked again the Vac lines. All are seated properly. MAF sensor seated properly and cleaned prior to install. No engine codes (other than the gas cap code - but that has been there since before install).

I dunno. Im going to have to get a spray bottle with water and soap and spray it on the vac lines to double check for leaks I guess.

Any ideas?

 

Forgot to mention. The truck idles high now. It will idle between 1k - 1300.

 

You may need to reset the ECU. And let it relearn the fuel curve. I installed a K&N on my 3.4 4runner years ago. I had to reset the to get things kosher.

 

Before the install, K&N instructs to disconnect negative on the battery, to which I did. Should this not have reset the ECU? Or is there something additional I need to do?

 

Nope, that is it! Unhook the battery(both leads) and drain off any residual energy by turning on the ignition after the battery is unhooked.

 

If you remove the KN filter, does it run better? Maybe the filter is over oiled and restricting air flow. Just throwing out a thought. Never had issues on any oiled filters I used in the past.

 

Give it some time..... When you reset the ECU, It needs time to 'LEARN' these new conditions.

I've had drop-in filters in an old Tacoma. I've had K&N cold-air intake on a Dodge Ram and never had any issues.

 

This ^^^

 

Sounds like a vac leak

 

Yeah. When I tested it by switching back to the old airbox + filter, it ran fine with no issues.

 

Try running it with k and n intake but no filter

 

Thats what I was thinking, even though everything is seated properly.. Going to spray some water/soap onto the lines and see if any bubbles form

 

I thought it may be this, considering after driving around for a few miles it seemed to get better, not by much though. The problem persists after having turned the truck off for the night, too.

 

Ill give this a try. Thanks!

 

Use propane to find vac leak

 

Propane? Why propane? How would I even do that?

 

If you don't know what you're doing, I wouldn't recommend trying it.

Propane will get sucked into the vacuum leak and the rpm's will rise.

 

I agree. It sounds promising, but I have never done that before. Water/Soap has always worked great, though!

 

Soapy water is usually for a pressure leak, vacuums won't blow bubbles.

 

What he said^^^