98 Camry Hesitation

Which spark plugs are you using? I've had very good luck with NGK-Platinums. May be worth considering replacing the ones you have in there right now.

thanks, I was going to replace them today as my last ditch effort to find a cheap solution.

But I will make sure I pick up those plugs!

How is the EGR valve area and have you cleaned out the throttle body and IAC?

I haven't gone down the path of cleaning the throttle body or it's related parts yet, because it seems to me that that would effect all 4 cylinders and not just 1 and 4. But if new plugs don't help out, I'll do that next.

Plug 1 and 4 share same coil pack. How are the spark plug wires?

I have to agree that it could simply be those 2 spark plug wires, especially if you replaced them a year ago with an aftermarket set. Remove each wire and check the resistance with a digital volt/ohmeter. You shoudl get about 25,000 ohms max. Don't be surprised if you can't get any reading. That means there is an open circuit; in other words, a break inside the wire.

Mike

Agree with Mike above. Problem with 1&4 would lean toward a coil/spark plug wire/spark plug issue. Don't worry about other things yet. Make sure your ignition system is working properly before moving on.

Let me know how things work out for you! Mine is the 2 & 3 misfiring! I'm going to replace the wires this weekend let me know how things work out for you!

IT WAS A BAD WIRE!!!!

I pulled the #1 spark plug wire while the engine was running (which I had done earlier too), but this time I rev'd the engine at the same time and saw a spark arcing between wires 1 and 4 just above the boot on the coil end of the wire.

They were still under warranty, so a got a free replacement set of wires, but I think I'm gonna get an actual Toyota set this week.

Thanks for all of your help!

I had a professional tech once tell me that cheap plug wires last about a year. If you plan on keeping the car any length of time, bite the bullet and go with the Toyota OEM's.

Another thing I like to do is to keep old parts that I have replaced as maintainance in an old bin. That is, if I know they were still functional, but replaced as part of general maintainance. They make good test parts if something goes wrong down the road. Old plug wires, if they were good when replaced, would fall under that category.

Mike

The aftermarket alternative NGK wire set has served me well for 3 years now, and counting.