HotRod68Camaro

iTrader: (29)

Well a few weeks ago I got the car tuned by MTI. They put in a base tune one evening and while I was at school the next morning they dynoed it. They said it didn’t need any corrections to the base tune they put in. The SES light was on so I thought nothing of it and later realized that they should have fixed that. Well come to find out it’s my knock sensors that are bad. Doesn’t that mean that they couldn’t have tuned it properly anyways? So they couldn’t have actually done what they were supposed to? So tonight the car was running hot, around 210*-220*F it was bogging at around 1500 and sounded louder/rougher. It shut itself off at a stop light. the clutch was not engaged. And when I pulled into the driveway it smelt like it was running rich. (I know I’v got true duals and no cat, but it still smelt noticeably stronger) I still haven’t replaced the knock sensors. Nothing has been changed since the tune.

So here are my questions:
1) What could possibly be wrong with my car?
2) Did I get screwed out of $500 by MTI?

Thanks

Kyle

Billiumss

iTrader: (11)

I wouldn't totally trust the tune if you had a bad knock sensor.

It looks like you don't have a bigger cam so your exhaust smell shouldn't be bad at all.

It could be possible that you are either running way rich or lean for your part throttle, hard to help with out knowing any scanner details.

BTW - Use a stock MAF if you can.

Bill

robertbartsch

Buy the OBD2 software program ($70) and check your Ltrims....

BBQLS1

The car will run in a "limp home" mode (run rich, pull out timing) until you fix your sensors. Replace them ASAP and see if things smooth out and the gas smell goes away. I don't know if MTI could tune with those sensors being bad. I guess if you have a wide band O2, you don't use the sensors the car uses. The computer is now adjusting to the current condition of the sensors.

HotRod68Camaro

iTrader: (29)

So did i get screwed out of $500 since they didnt notify me that the sensors were bad and probably didnt do a real tune?

Kyle

Billiumss

iTrader: (11)

I would call them up and ask them if they drove your car to get some real data for part throttle tuning. I am guessing they didn't.

I am surprised they charged you that much for the little work they really had to do. The drivetrain is basically stock. I charge people about half that for a full tune (H&C combos).

MTI is a great compnay and they should take care of you...

BBQLS1

It seems a bit high for the tuning, but I would ask to speak to the owner or shop manager about it, be nice and he may try to help you out.

BBQLS1

I would have notified you and sugest you get the sensors fixed and then come back.

BBQLS1

Do you have to have the knock sensors to tune the car? I guess for part throttle it may be more likely.

HotRod68Camaro

iTrader: (29)

Well and it will retard the timing if i am correct and will not be able to show the true performance.

Kyle

Honez

That is suppose to be one of the best shops in the country for our cars, I would take it back and talk to them. I have known guys that deal with them and they have always been first rate about fixing stuff and makeing sure the customer is happy. If you do take it back and get something different I would like to hear so PM me.

HotRod68Camaro

iTrader: (29)

Well i talked with Wayne, he said that it is possible for them to tune it with bad knock sensors. He siad he wouldnt be able to tell what my problem was without looking at the car. Suggested just replacing them. Now ill have to scrounge up about $100-$130 depending on if i plan to replace the knock sensors harnesses. The car drove fine today though, it didnt die on me although it felt like it would bog a few times but barely noticeable.

Kyle

Another_User

My opinion is that you got screwed. How do you know your knock sensors were bad? PCM code? Which one? Was this the first time the vehicle had ever been tuned?

BBQLS1

Yes, but when you are writing changes to the computer does it ignore the sensors until you pull the laptop out of the loop and let the car's computer take over?

Another_User

As far as I know, you can't program PCMs while the car is running with any software we have available. HPTuners and Edit don't care what your sensors are saying. They just write to the flash memory. Then you PCM re-adjusts according to the new values in whatever you changed.

HotRod68Camaro

iTrader: (29)

I had the check my ses light and they told me it was low voltage. I dont know y they didnt tell me the first time.

Kyle

BBQLS1

Cool thanks.

BBQLS1

Now, I think you got screwed. I don't know it was intentional. Sometimes you get screwed because someone did not know what they were doing.

Another_User

I do have to correct what I said before. None of the programs permanently program your vehicle while it is running. You can make temporary changes though. If I didn't know better, I would think that is what they did...but I have no idea why anybody would do something that stupid, unless they really didn't know the changes were not permanent.

BBQLS1

Thanks for the info.