cDUKES

iTrader: (3)

Hey guys , some quick background information:

2005 MT enthusiast
53k miles

HKS hi-power (put on around 45k)
AEM CAI (put on around 40k)
Berk HFCs (put on around 51k)

About 1000 miles before the Berk HFC's were put in , the "service engine soon" light came on , almost right on the dot at 50k. Call me stupid, but I figured the light came on as a reminder just for a service , since it came on at 50k.

So I FINALLY bring the car to the dreaded dealership (first time back since I bought the car there) and they agree to do a "free" diagnostic, oil change, blah blah whatever the 52,000 mile service was in the booklet they gave me.
Dropped the car off this morning and of course was already hit with a 125.00 inspection fee (surprise!!) . Before leaving , I told them to call me before they do anything to my car regarding new parts, since I didn't want to come pick up the car with a 3,000 dollar bill for an oil change and a gasket.

So I pick up the car and told me they ran the "service engine soon" and got a handful of codes. they told me it was the same thing as a "check engine light". this is what the diagnostic read , quoted exactly:

ecm vehicle has aftermarket exhaust from the manifolds back. the rear o2 sensors are set back off the exhaust stream about 1 1/2 to 2 inches. both o2 sensors read .28v plugged in or unplugged. called tech line. did the tests they wanted me to do, found no opens or shorts. tech line says that the one o2 sensor is bad but the ecm is not seeing the voltage from the front a/f sensors. i can see that the a/f sensors are at 1.5v (spec) with the consult III. tech line said that if the sensors are reading 1.5v at 2000rpm than the ecm is at fault. ecm would not be covered under warrenty because of the aftermarket exhaust. the aftermarket exhaust is the original cause of the ecm failure. if left this way for a long period of time there could be possible engine damage.
One rear 02 sensor and engine control module burnt out.

They said the final charge to get everything fixed and replaced would be ballpark over 2,000.

So, is the stealership at it again or should I really be worried? Either way I'm going to have it checked out, but I just want to avoid these guys, they've given me nothing but trouble since day 1. Just wanted to run the situation by you guys and get some input before I open the wallet

The car drives fine and I havent felt anything different ever since the bolt ons were installed.

Also, I have a 5/16" plenum spacer on the way which would be my last bolt on , which means a tune. Would this "burnt out ecm and o2" put me at any risk if I were to get a tune after the spacer is put in?

Thanks guys, sorry if this was a lot of nonsense in one post, just looking for some input and or clarification.

davidv

iTrader: (2)

There is a considerable difference between "ECM burnt out" and "ECM failure." With a burnt out ECM the car will not run.
So the ECM is 95 percent functional, and the problem is reading oxygen sensor #2? Sensor #2 is no big deal but...

My concern is the note about sensor #1. This is the sensor that provides feedback to the ECM for air-fuel ratio. That is important stuff.

BTW the idea that the oxygen sensors, or any sensors for that matter, broke the ECM is silly. The ECM will cope with frivolous readings from sensors. It simply goes into the limp mode.

edd2045

iTrader: (11)

what he said ^^ i work at a shop, and like david said a burnt out ecm wouldnt let the car run, what their tool is seing is probably a slow response from the o2 sensors because of the hfc

davidv

iTrader: (2)

Always happy to help. If you have other questions please do not hesitate to waste my time.

cDUKES

iTrader: (3)

thanks guys, appreciate it !