So my check engine light came on a week ago and ive been rolling around and finally decided to stop by the local dealership. Well i got codes P0355, P0410, P0172 and my head exploded. Ive never had 3 codes at one time so my heart dropped. A little history about my car; 103k, 2004 VR, new dealer CAT put in at 70k, new engine around 80k. No History of plugs, coils, wires changed (got the car at 35k). I don't believe they even changed them when i got the new engine. The guy looked so sad when he came out and told me the bad news, he was quoting me all sorts of prices for s starter, solenoid, and air control valve and said around 1000 just to get that stuff fixed. Then he also said it could be losing compression but ive had that issue before and my car definitely didn't act like it did now back when it was losing compression. When i lost compression in my first engine i had the hot start issue, i could floor it and it would barely move etc. He basically said i should trade it in blah blah.

So guys, ive done some searching on a few codes, 172 is running lean, fuel to air ratio etc but i don't know where to even start. I do have a fresh set of ngk plugs, wires and some coils at my house should i attempt to put that in? Also, i read around here that cleaning the MAF sensor could help a bit. If anyone is in houston and would like to coach me on changing plugs, wires, coils, and cleaning MAF there's 60 bucks in it for you just to coach me. (Located in Houston woodlands area).

Last, my car is idling off when im in first and i hit the gas. If i give it some power it wont turn off but if i dont give it enough power turns off. Runs normal on freeway but it makes that deep sound when on the street at a light upon giving it gas like its not getting enough gas or something. Id appreciate any help i can get, paid my car off was hoping to ride around for a year with no car note but this is for sure a fork in the road to that plan...

 

You don't need a coach for those things:

Plugs: Lift car & take the driver side front wheel out, plugs will be in plain view and easy to access. Trailing plugs go up, Leading go down.

Coils: where did you get them from? If it's BHR it comes with a very detailed guide on how to install, if it's OEM replacement it should be easy as well. Same with the wires, if you already took the wheel out it's easy.

MAF: It's on the intake tube, buy some MAF cleaner from Autozone, clean throughly and let dry. It's this one

You should also clean the ESS sensor, it's this thing over here

You should also check your throttle actuator, it could be stuck open/closed from oil.

I'll send you my Paypal info over pm, j/k.

 

Don't take the dealer's sad face at face value.

With your coils, wires, and plugs being 68,000 miles old, there is pretty much no chance of diagnosing anything else properly until you replace those. Chances are you have had failing coils since before the cat failure since the typical failure rate is that at least one of the 12 pieces (4 coils, 4 wires, 4 ignition) by 30,000 miles. You have probably just been managing to limp it this far with a fresh engine and fresh cat. Chances are also good that your current cat is nearing death from neglect of your ignition system.

4 coils, 4 wires, 4 plugs for ~$200 from auto part stores, having spares on hand that you can sub in will bring that down quite a bit.

Cleaning the ESS and MAF is easy and nearly free.

I suspect your car will run like brand new with the ignition replaced and sensors cleaned. However if you still have codes and/or driveability problems, come back and we can start pointing you in other directions. Buying the ignition stuff isn't ever wasted, since you are clearly over-due anyway, and a failing ignition will muddle every attempt to find other problem sources.

 

Thanks man lol. I will attempt this stuff this weekend in hopes of not having to cough up much dinero. Wish me luck

oh yeah and if you wanna take a drive to the woodlands feel free man lol

 

Thanks for this post. I feel alot better for sure. I looked at the guy like man there's no way the engine could be failing again its not even having compression issues the throttle response and etc is great. like you said, fresh engine and cat could have kept me afloat for a while. He did say there's no misfire codes but again, im 99% positive they haven't been changed since ive owned the car. Will get on that this weekend.

On the plugs, coils and wires, i spent 220 at advanced auto parts. The plugs are the oem ngk trailing and leading, stock ngk wires, and some bwd intermotor coils. The reviews were good so i said 30 bucks less than oem what the hell. I only wanted to use as a backup but a year ago i ordered a agency power midpipe and never used it because my cat was good. If i have to put it own i still have it just in case. Really not looking forward to a super load rotary and smelling like gas everywhere if i have to use it. Thanks again guys!

 

The most common reason for the 0172 code is a small vac leak...like the VFAD nipple hose falling off ....it tends to max out the STFT at idle...and throws the code..but runs normally other than that

 

At idle my car goes from 1000 rpms to 0 back and forth like its about to turn off, sometimes if actually cuts off sometimes it doesnt. Kills me when it makes that deep tone when i hit the gas! Sounds like a burp or something.

 

Yes, that could entirely be from a vacuum leak. If it was swinging across RPMs at a higher range, then I'd say your neutral switch was having a problem, but that low plus the lean code could easily be a vacuum leak.

 

Mid pipe was the best mod I ever did If you keep the stock big *** muffler though it won't make that much sound. Noticeably MORE, but nothing outrageous. I installed mine right when my cat failed and whoa buddy, it opened up a lot of power.

Just don't ever start it in your garage, even if the door is open. Your nose will burn for a few days.

P.S. Bad ignition kills cats, which kills engines. Fix it!

 

P.P.S. Ignition is easy, once you take everything off it's easy to put back on. The only problem is the airbox. It's a PITA to put back. Simple, but a pain. PM me if you need help.

 

I may consider the mid pipe soon since it has been laying around for a year and set the cat aside; but that will be after I get all these damn codes fixed. Thanks for the advice!