I just had my motor rebuilt about 3,000 miles ago. When I did that, I replaced everything I could think of that would be in a tuneup (plugs, wires, cap, rotor, etc.). About 500 miles ago, I noticed a rare sputter here and there, only when cruising. Now it's way worse. It lurches constantly when driving down the road. It feels like the key is being turned off for a fraction of a second, then back on, over and over again. It idles perfect. It stops sputtering while accelerating, or when I let off the gas and coast. The plugs look perfect, but there is some black soot in the exhaust pipe. Please help.

 

Anybody have any ideas?

 

Hi Thomas,

Does it sound like my problem:

4Runner w/ 22RE - temperature sensitive - low power, stuttering, surging, bad idle

 

cat 02 fuel filter?

 

stretched timing chain or broken guides / failing tensioner?
fuel injector with bad spray pattern?

 

i have same prob too. i noticed it last year in the summer but it seemed to have gone away over the winter. now that it is warmer i've noticed it again. It doesn't happen all the time. just like you decribed Thomas. just a real quick interuption in the ignition while driving (maintaining speed) but is fine while accelerating or completely off the gas.

 

Has a new timing chain/tensioner (when I rebuilt the motor).

 

How would I check the 02 sensor?

I've never changed the fuel filter, guess it could be that (wouldn't it affect it under acceleration too?).

 

I bet you replaced the spark plug wires with a bright red or blue set of after-markets? I wonder if that's the prob.

 

Fuel pump may be crapping out. Kinda sounds like it...a lot. Particularly since it's happening under load = losing fuel pressure/delivery.

 

nope not under load. just at a steady speed. no probs under acceleration or decel.

 

Well, it still could be the fuel pump. Last mine went south, it started out while cruising and then progressed to when accelerating.

 

I had the same prob then i seafoamed it and it went away. TRY SEAFAOM IT WORKS!

 

Tried the seafoam. The only thing it did was relieve me of ten dollars.

Decided to try changing the plug wires since they were under warranty. PROBLEM SOLVED!!!! It finally runs like it has a new motor (it does). The brand new Bosch "Ultra-Premium" wires went bad after only a few hundred miles. I think I'm about done with Bosch.

 

i'm probably due to change mine too

 

well desertcox did it fix yours. mine is doing it too!

 

I had a similar problem and just fixed it.
Back story
87 4Runner, 5speed, 22re. Completely rebuilt the engine, top, bottom, all accessories, clutch, everything I could think of. After +- 5K miles it started surging only while maintaining speed. Acceleration, deceleration, and idle were fine. I found out that I must have broken one side of the connector on the TPS sensor, because the metal retaining clip was missing and it was half off of the TPS sensor. I plugged it all the way in and secured it with bailing wire. Now it runs like it should (brand new)! Not that someone with these symptoms would have the same problem, but check, adjust, or replace your TPS.