Bought this car about a month ago and have done a few maintenance things to it. One of the known problems is a transmission solenoid going out. A new problem it has that I noticed on the way to work yesterday morning is an engine stutter that causes the CEL to flash. It comes and goes and as of this writing, I dont yet know what codes it has. Has new plugs and it doesnt sound as though it jumped timing. I also noticed a lack of throttle response when the CEL is flashing which may be a normal byproduct of a flashing situation. One other thing I did just notice is when its idling and sitting still and does it, the exhaust sputters like its losing spark maybe.

Without knowing the codes at the moment, anyone have an idea of where to start looking? Car had 275k miles so I'm expecting things to need replacing soon.

 

flashing CEL = misfire.. Did you use OEM plugs? Check the coils next,

 

Plugs were replaced with OE NGK Iridiums. I wont cut corners on this car so everything possible will be OE parts.

 

Good man Check your coils next then.

 

I'll be going by an Autozone in the morning to see what the code is. If it's not a spark issue, what other "normal" TL problems would this sound like? I was thinking intermittent throttle solenoid problems but trying to steer myself simple.

 

your head is in the right place.. Stay simple.. it's very likely the coil or worse, a fuel injector

 

I hope it isn't an injector. I'm very mechanically inclined as I've built several cars in the past. I just need it to be simple because my bike has to go down for a short period of time.

 

I'm also getting really bad gas mileage or my tank is much smaller than I thought it was.

 

Misfires mean bad gas mileage

 

Yes but the mileage was bad prior to this issue. I'm gonna have it scanned first thing in the morning and see what the issue is. I drive 55 miles one way to and from work so I need to figure this thing out.

 

P0300
P0301
P0303
P0306
P0123
P0420

Sounds like my APP sensor is causing a chain reaction.

 

I believe that P0123 is not a code for APP sensor (accelerator position sensor).

It is for throttle position sensor, and that refers to actual position of the plate in the throttle body. So the problem would be either "throttle body" or "throttle actuator control module" (or wiring in between).

That's what AllData suggests in terms of testing. If you want the rest of that document let me know.






Preferably under load (with throttle body connected), check if TB sensor is receiving ground and Vcc. If throttle body moves with engine OFF and gas pedal depressed, check outputs. They should change depending on plate's position.
Moving plate by hand is not recommended, but if you suspect it's faulty then you won't make it worse, right?

 

p0300 to p0301 p0303 are random misfire codes, that means you have a coil pack failure. Also p0420 is a catalytic converter error likely stemming from said misfire allowing too much fuel to pass unburnt into the cat. Hopefully the cat is still okay

 

I am going to have my battery checked in a bit. This thing runs good. Just not sure why those codes all popped up at once. My guess would be the TPS caused the chain reaction. Meant to say TPS and not APP in an earlier post.

 

Believe I determined my issue to be the previous owner using regular unleaded gas. No more misfires as of now but the dreaded P0420 code is recurrent even after multiple heat cycles and clearing the codes. With 275k miles, I guess it wouldn't hurt to rebuild my exhaust to my liking.

 

How old are 02 sensors? I know it’d throw a code for them, buttt figured I’d ask.....

 

I'm assuming they are 275k miles old. The previous owner didnt advise. I bought the car knowing things would need to be replaced and I'm okay with that. Paid a good price for an 08 base with navigation.