Number 1 cyl

[RavTufts]

I recently acquired a 1997 Rav4 with 176K . The car sat for a few years . After fixing a small tranny leak and replacing the brake pads I put the car on the road . I am getting a miss on #1 cyl and it is throwing check engine light saying something about low oxygen in #1 . I replaced the spark plug wires , inspected the cap and distributor . Not knowing much about the 2.0L engine I was wondering what the first things to check should be . I like to believe in the Ochim's Razor approach that it is always something the most simple and easily overlooked.
I am also getting what sounds like a screech from the rear drive line on occasion .

Thanks

[Carbon]

Originally Posted by RavTufts

I am getting a miss on #1 cyl and it is throwing check engine light saying something about low oxygen in #1 .

I suspect the code you got indicated something about an oxygen sensor on bank 1. I don't know if your engine has one or two banks. Somebody here will. If there is only one bank, looking up the code may still reference bank 1.

Find the code and do an advanced search within the 4.1 forums for that code. The code will be a P followed by 4 digits.

[RavTufts]

Thanks I will do that and see what the code actually was and share it with the group .
Thanks Again

[RavTufts]

JUst got off the phone with my friend with the code reader. It is P0301
Thanks

[Ken Allistone]

P0301 misfire on number one could be wires (you say you replaced them so should be ok so long as you did not use Bosch wires?), spark plug - use NGK, or injector - try a good injector cleaner. Otherwise an air leak on the manifold (usually around the gasket to the head) but I doubt it would only trouble one cylinder.
Usually it is the wires that fail on 4.1 Rav's and cause this fault, Denso wires were fitted from new.

[Carbon]

It is not always easy to see a hairline crack on a distributor cap. You might be able to see arcing in the dark if you find a dark-enough place and let your eyes adapt to the dark. Arcing could be on the outside of the cap, or hidden. Plug wires can sometimes arc, although that seems unlikely with new wires.

One thing to consider is to move parts between cylinders. For example, is a spark plug wire close enough to the same length as another? Swap it with #1. Ditto plug or injector. See if the code followed a part to a different cylinder.

Also, plug wires can be checked with an ohmmeter. Less than 100 kOhms is probably good.

[needa]

Originally Posted by Ken Allistone

P0301 misfire on number one could be wires (you say you replaced them so should be ok so long as you did not use Bosch wires?), spark plug - use NGK, or injector - try a good injector cleaner. Otherwise an air leak on the manifold (usually around the gasket to the head) but I doubt it would only trouble one cylinder.
Usually it is the wires that fail on 4.1 Rav's and cause this fault, Denso wires were fitted from new.

^this

i battled p301 for years before i finally broke down and bought the denzo wires. its not just bosch either. its any wires you get from autozone or advance. which pretty much means... get online and buy the denzos. you will not be sorry. i have a thread the i bumped yesterday with specifics on what site to use and how to get 15% off (i think 15%) just sign up on the site and then dont order anything and you will get an email. a new year has come... so the old discount code may not work. if i remember... i got em for $37 shipped. they are the only wire set that has lasted me faithfully... for more than two weeks.

[RavTufts]

Team , I went through everything evertyone suggested and went ahead and diassembled to ther point of accessing the FI system. Can a person change just one or do you have to remove all of them . Secondly is there a spec to check the injector electric connections ?

Thank you .

[Ken Allistone]

I removed all 4 injectors and had them tested on a rig, it checks the spray pattern and flow rate. If either are out then they can be cleaned using ultrasonics. I had to find a shop that worked on high performance cars to do this.
If there was any other fault with an injector then I 'guess' you could just change one but you would need to be sure the other 3 were 100%.
Have a look on here http://www.autoshop101.com/ under technical articles/fuel delivery and injection control. I seem to remember using a multimeter on mine before removing them to check resistance but I cannot find anything on that now, sorry!

[RavTufts]

Ken , Thanks . The new injectors are expensive . I will look around to see if there is a shop around here that can test mine. thanks again.