Timing won't stay steady

[Elvota]

3.0, V6, newer timing belt, wires, dist cap, rotor...

Timing marks jump 2 or so degrees at seemingly random intervals. Engine is warmed up and seems to idle just fine. I have no real operational concerns except I think there is a lack of power, even for a 3.0.

Any ideas on what would make the timing not sit steady? Something mechanical or something electronic. Maybe a sensor or computer trying to compensate for something?

Thanks

 

[grant5127]

What is your rpm idle? is it smooth? do you have your jumper wire connected correctly? you say newer timing belt.. did it have this problem before the belt swap?

 

[Elvota]

Idle RPM reads 1,000 smooth at the guage, but when I connect a meter to the IG port I get 750-800. I think my tach is off actually as I had a loose needle before.

Not sure about timing before belt. I wish I had checked now, would have helped narrow things down. I am wondering if it is from a lack of tension on the belt itself. The belt doesn't actually slip, just goes slack/ tight and allows things to change a bit.

Belt has maybe 5,000 - 7,500 miles on it.

Additional ideas or tips are still more than welcome however.

 

[grant5127]

I would replace the tensioner.....

 

[grant5127]

Let Me ad a bit more to my post... anytime some one ask me to do a belt replacement... I strongly advize replacing everything associated with the belt... water pump included...

 

[Grim Reaper]

A little bit of bounce is not uncommon.

With the jumper in then the things that will effect that the most is belt slap from lack of tension and Knock Sensor hearing something and dumping timing.

I haven't messes with a 3.0 but if its like more timing belt motors the tensioner pulley is locked down after the spring sets the tension. Its not a bad idea to retention the belt after about 5k once it get a little normal stretch to it as it breaks in.

If you are sure this isn't the normal little bounces you will see then do a compression test on it. A Blown head gasket can make noises the Knock sensor will hear and react to.

 

[86HJ]

Your timing will not sit steady. It will jump agound 2-3 degrees when idleing. Your timing light is probibaly not fast enought to pick up every time it fires. Just like when you check your engine idle it does not sit at 850rpm exactly. I have built over 300 of these 3VZE engines and it sounds normal to me. Good luck

My thoughts/opinion

 

[Elvota]

Actually, I think I got it figured out today.

Tried messing with the TPS, only helped a little. Swapped the distributor with one from a salvage truck and bingo... steady timing. Adjusted to 12 and engine seems to run very well. Smooth idle, even power, but I only have 20 or so miles on it so far.

Time will tell, but happy to be moving in the right direction at least. My original dist. span very, very easily when compared to the newer one. I can only guess the bearings or other might have been making for the uneven timing.

So, maybe I was lucky... or maybe you have 300 motors to tune-up.

Sorry to be a smart-ass, I did appreciate the feedback with a suggestion. All ideas are helpful.