I've had an issue with my 2008 Rav4 2.4L Sport for about 2 years now. I first noticed the problem when going up a ramp to an elevated roadway that the engine suddenly lost power and would not accelerate. The Check Engine, VSC, and Anti Skid lights came on and stayed on. The engine just loped without being able to accelerate beyond 30 MPH. After shifting to a lower gear (which revs the engine) it will usually allow the car to resume the regular power level with normal acceleration. However the lights stay on which renders the cruise control inactive. (I know this is a safety feature). The Check Engine code says that I have a Cylinder 4 Misfire.
The dealership changed all four ignition coils and all four plugs. The engine ran normally for about 2 weeks and then the same issue happened. I returned the car to the shop and they changed the computer. Once again it ran well for about 2 weeks and then the same problem started. With $2400 now invested, naturally I am concerned about anymore trips to the service department.
After some internet searches, I learned that it would be good to recheck the plugs and gaps. I did so with no changes to the problem. I also decided to swap the ignition coils around to see if it would show a different cylinder misfiring, but it still only shows a misfire code for the #4 cylinder. I checked the harness to the coils (especially the routing to the #4 coil) and all the wires appear to be clean and intact. I've run some injector cleaner through the system thinking that this may help with the fuel/air mixture.
Finally I broke down and decided to drop the fuel tank and replace both the in-tank fuel pump and filter. Still have the problem. When the car runs on flat ground in normal operation, it runs fine (even though I have noticed a slight drop in fuel mileage/economy). Yes, I've even changed the fuel cap for the possibility of a faulty seal. The problem still rears its head under the load of an on-ramp climb.
I'm not wanting to just start swapping parts in hopes that I'll get lucky. I'm simply hoping that someone can steer me in a direction that makes sense to try before settling on scrapping this old car. Any suggestions?
The dealership changed all four ignition coils and all four plugs. The engine ran normally for about 2 weeks and then the same issue happened. I returned the car to the shop and they changed the computer. Once again it ran well for about 2 weeks and then the same problem started. With $2400 now invested, naturally I am concerned about anymore trips to the service department.
After some internet searches, I learned that it would be good to recheck the plugs and gaps. I did so with no changes to the problem. I also decided to swap the ignition coils around to see if it would show a different cylinder misfiring, but it still only shows a misfire code for the #4 cylinder. I checked the harness to the coils (especially the routing to the #4 coil) and all the wires appear to be clean and intact. I've run some injector cleaner through the system thinking that this may help with the fuel/air mixture.
Finally I broke down and decided to drop the fuel tank and replace both the in-tank fuel pump and filter. Still have the problem. When the car runs on flat ground in normal operation, it runs fine (even though I have noticed a slight drop in fuel mileage/economy). Yes, I've even changed the fuel cap for the possibility of a faulty seal. The problem still rears its head under the load of an on-ramp climb.
I'm not wanting to just start swapping parts in hopes that I'll get lucky. I'm simply hoping that someone can steer me in a direction that makes sense to try before settling on scrapping this old car. Any suggestions?
