There has been alot of talk on here about lean tunes and the tuners who sell them, here are my questions.

1. If you have a lean tune what symtoms will your car have

2.. What type of damage will result

3. How many miles will it take before the damage is done


Many of us have e-mailed tunes or bought the tuner package with the tune, from one of the popular three tuners, I included. I never read or signed anything saying buy at your own risk this tune may be defective and ruin your car, you must have a dyno tune. You buy these tunes in good faith not expecting them to be defective.
If these tunes are defective I would hate to be one of these tuners, and have class action law suit for a bunch of damaged vehicles.I know Doug from Bamachips went to St. Louis for some dyno tunes, did these cars show a lean condition that could result in damage, also what was the average h.p. gain with the dyno tune from the canned tune.

 

Just some well intentioned answers......

You know it is lean by monitoring AF ratios... (Wideband Sensor) if you are messing with your car one of those is well worth the money......

The effect of running lean is the increased possibility of detonation.... (combustion in the chamber before it is finished compressing.... can ruin your pistons and or other internals)

I will not comment as far as who's tunes are lean or not..... I don't have personal knowleadge..... but typically a CAI that requieres no Tune is either worthless or runs you lean IMO...

 

First off... Dream on about going after the tuner.. They are not liable, and if you have ever put your car up on a dyno you know you have to sign a waiver.

And incase no one has told you this yet, if you can't afford to have something break.. Then don't mod it.. Only way you will be covered is if you leave it 100% stock.
Any mod has the chance you will not be covered.

 

I wanna know too... what are the warning signals that would occur if I were running lean? I want to be able to detect it, if that were the case.

 

Install a widwband gauge and sensor and monitor it ........ That's the only way I know

 

Only a couple ways to really know if you are running lean. Simplest is a Wideband meter. Next would be an EGT (Exhaust Gas Temp Gauge).
Then the PIA way is to pull your plugs. Are plugs are not as easy to read as the older copper ones.

Another sign that you could be running lean would be the car pinging or pulling timing...

 

If the tune was dangerously lean, then wouldn't the engine knock? I understand that knock isn't always audible. In that case, couldn't you just datalog with your XCAL2 and monitor the knock sensor?

What about check the long term and short therm fuel trims? Would that work?

 

Go get dyno'd just to check the readings...