Hey, Guys first time posting. I have come to you asking for help with my 2003 TL Type S with 200011 miles. It is idling really rough and has lost a significant amount of power and is trowing a bunch of codes. The VSA, /!\, and Check Engine Light are all on. It was running fine until recently, but then on my way to work it just started doing all this. I did replace the plugs already and I do not really think that it helped. If there is a duplicate thread about this I apologize I looked for a bit and couldn't find anything on it.

-Thank you for your help or advice.

These are the codes that it is throwing.
25-1 Yaw Rate Sensor malf
64-1 Sensor Supply Voltage malf
83-1 Engine Control Module Powertrain Control Module Relationship Malf
P0301 Cyl1 Miss-fire
P0302 Cly2 Miss-fire
P0304 Cly3 Miss-fire
P0305 Cly5 Miss-fire
P0300 Random Multiple misfires
P1399 Missfires detected
P0705 Trans Range Sensor Malf

 

A low/weak battery can cause all sorts of ECM errors and throw weird codes. I'd replace that /clean the terminals before checking all the rest of the stuff. 64-1 / 83-1 and such usually stem from battery or alternator issues.

 

Hey, thoiboi

I did forget to mention that I did get the battery tested by AutoZone and they said it was fine. it is about six months old, and the terminals seem fine.

Thanks for the response though!

 

I've had batteries 'test fine' by the stores but it still ends up being the problem.


Check your alternator next if you're confident your battery is good.

 

Alright! I will start there then. thanks!

 

I'd be suspicious of a bad ground. There are three major grounds from the battery. Body, transmission and engine. Check them all.

 

Alright I got my multimeter out and tested both the battery alone is pulling 12.55 and with the car running I am pulling 14.43
I reset the cars Computer and drove it to Autozone because I didn't reset it after replacing the plugs Only the Check Engine Light was on. (AutoZone is about 6 miles) and the only code they could pull was P1399 Missfire in any cylinder.
of course halfway home on the return trip The VSA and /!\ light came on again...

Car off

Car running

 

I will check that out thanks!

 

Okay I tested the grounds, borrowed the battery from my Corolla for testing purposes that I know is good and has the right CCA, and cleaned out the intake manifold thing that seemed to have a lot of carbon buildup. The only other thing I can really think of is possibly bad injectors? But that's a lot of them to just randomly go bad over night..

Can you guys think of anything else to check before I just take it to a mechanic?