Loss of Power!!!

[BFG Previa]

Okay, make a "wa-wa-wa-wa-wa-wa" sound out loud and then rock your head back and forth at the same time...that's what it feels like in my '91 AWD under load up a hill once it's warmed up. Those are the constants in this issue. Runs fine cold. I can put it to the floor and it goes well when cold.

List of constants:
1. Vehicle must be warm before acting up.
2. Vehicle first did it under load, downshifting from OD to Drive on a hill (Yes, it had lots of fuel).
3. Tonight when it started acting up I put it in neutral while going about 80km/hr and depressed the gas pedal and it made the "wa-wa-wa-wa" sound, without any load!

Here's what I replaced in December 2011 that has anything to do with fuel or electrical:
1. All new spark plugs
2. Valve Cover Gasket
3. Fuel Filler Neck
4. (Catalytic Converter was replaced about one year ago).
5. Toyota muffler was installed in 2008.

This issue first started around the beginning of March 2012. I've now replaced in the last two weeks:
1. Plug wires with NGK brand.
2. Rotor
3. Cap

I picked up a fuel filter today. Hoping that's an easy Re&Re in the garage. I'm wondering if this might be an injector issue???

Here's a link to a video I took tonight while driving up a long hill...listen closely around the middle and you should be able to hear what I'm talking about.

http://www.youtube.com/watch?v=bNxAZ...ature=youtu.be


Any thoughts on this would be greatly appreciated. The van has 384,000 km's on it. I'd like to see it pass 500,000 km's.

Thanks in advance folks

[BFG Previa]

Also, just checked the fuse holder at the battery and it was spotless. The CEL Light comes on when key is turned on and then shuts off as soon as engine fires.

I'm attempting to eliminate parts and pieces one step at a time...here's my thought process of what to replace next:

1. Ignition Coil (That's the one with the wire attached to the cap).
2. TPS and retrofit harness (Apparently a wire goes bad between the TPS & ECU?)
3. Fuel Filter
4. Ignitor

I've read a bunch on the forums and these seem to be common things to replace that I have not yet replaced. I'm tempted to pull my Cat off just to see if that helps, even though it was new a 1-1/2 yrs ago.

[BFG Previa]

Checked for codes last night...nothing...steady blinking on both CEL and OD lights.

Exhaust flow is strong when driver idles up too so I doubt the cat is clogged.

this sucks...

[BFG Previa]

Turned out to be a faulty Fuel Filter...had replaced it only a couple years ago but I suppose something messed it up somehow.

I've been driving it for about a week now and took it for a long weekend road trip and it didn't miss a beat once.

I was hoping it was something simple...especially because I was getting nothing from anybody on the forums!!!

Well, I suppose for $30 it's a good place to start when similar symptoms arise again.

Cheers!

[Rey8]

Thanks for the followup post. Its always nice to have a solution for a certain symptom to be documented here.