My engine (3VZE) has developed a very anoying problem. It stutters when under heavy load. There was no mods or maintenance that proceeded this, as it started aprox 800 miles into a 2500 mile trip from Montana to Virginia. Doesnt happen when the engine rpms are below about 2200, Most noticable when trying to maintain 70-75mph going uphill on the interestate. I have absolutly no idea what is happening. It almost seems that its getting starved of fuel during high demand, so I replaced the fuel filter today, but it wasnt old (replaced about 9000 miles ago) Any one have any ideas whatsoever??? I'm really stumped on this one.

 

kevin: when is the last time you changed your spark plugs? Sounds like weak ignition.

If plugs are OK, check that coil.

 

could be as simple as a loose plug wire. check both ends.

 

yup... check all plugs and wires. You may also have a fouling injector. You could try some injector cleaner like seafoam or send them off to www.cruzinperformance.com and get them like new again.

 

I agree with the other guys. I would also like to compliment you on a cool avatar picture!

 

could be a number of things. iginition could be it but i think more likely it is your fuel system. check your filter and your sending units.

 

Reading the forums it seems like any troubleshooting session should start with a seafoam

 

Ill pick up some seafoam tomorrow and give it a whirl, and post results.
thanks for all the advice so far.

 

If it just randomly started, I doubt seafoam is going to fix it. I'd check plugs first and go from there. I think my next move would be to the fuel filter.

 

Kevin286, I would hold off pouring hard detergents like seafoam that have at best questionable benefits. As you see with the filter recommendation, some advice that you receive here is given without even reading your original post.

 

Check for proper TPS adjustment. Also your MAF sensor for proper ohms (3vze has what is called a "vane flow" type MAF). Ditto on stuff said above.

Seafoam is over-rated in my opinion. It's just a top end cleaner.

-Wrench

 

OKay, guess I have my work cut out for me. Anyone know if there was a write-up on testing the TPS sensor? I'll admit I'm not familiar with it at all. Also, if I replace my spark plugs, can I go with +4's ? Ive heard some people's rigs run like poo after installing these, others work great. Stick with nkg? Again, Thanks for the help

 

If they need to be replaced stick with NKG. But if they don't, just inspect them. In fact, that's probably the first thing to do with those symptoms.

....and now onto more wild guessing....

 

Well I drained my gas tank, and replaced my fuel filter. Seems to have fixed the problem; However, I am now inspired to check my whole ignition system, Hasnt been done since I bought it 20,000 miles ago. Im ashamed Thanks for all the imput guys