Don't reset the ecu. That does seem a little low but the VA cars use dam more frequently.

Check for leaks in the intake, clean the MAF as well.

 

Couple months ago I bought a 2015 stock WRX with 80k miles, added a cobb AP, which showed .625 DAM, reset ECU to cobbs stage 1, did scheduled maintenance items, plugs, filters, MAF clean, etc. DAM would still drop after a couple days of driving.

Did an E-tune with BrenTunning, who suggested running a dose of VP Octanium. DAM now is now solid 1.00, but I have learned to minimize det/knock by not whacking it to WOT below 3k RPM, I roll throttle up to WOT and frequently do full pulls. Think carbon intake valves are an issue with most DIT engines, including my 80k car. I got stuff to do a walnut blast, but haven’t made time to do it yet, may ask about an update tune once I do the decarb clean.

Bottom line, guessing the Octanium and aggressive driving has reduced carbon some, and avoiding stomping WOT at lower RPMs is keeping DAM @ 1.00. Also custom tune was $ well spent for me, each car is different, OTS tunes are generic. And the new tune/map adds a bit of hp/torq and is a big improvement in the throttle map and the way the car drives, keeping the car healthy and me happy. The car does an awesome job as my daily driver and is a hoot to drive!

 

Exactly what do you think octanium did?

 

Product description - Buy VP Octane Booster - Octanium® | VP Racing Fuels

 

Product description - Buy VP Octane Booster - Octanium® | VP Racing Fuels

I know what it is. That's also leaded and will not only obliterate sensors it will destroy the cat. Leaded fuels are also notable for driving down the average IQ in the US for decades.

The non leaded variety is a little easier on emissions systems, but if it cures knock you've got another issue.

 

Thanks for replys, l just put 2 gallons of e85 in a full tank of gas reset ecu and now its been at 1.00 dam for weeks.

 

Wait. Is the car tuned for E85?

 

No but it acts like a octane booster

 

You are effectively creating E10 if the pump gas used does not have ethanol. That's tolerable, but at the upper limit.

If the pump gas you are adding already contains Ethanol AND the E85 is truly 85% Ethanol, I'd be careful - you are creating E20 which is out of the range that the OEM fueling system can effectively adjust.

Be careful.

 

So l had a dam drop before to 0.68 and l simply reset the ecu and added few gallons of e85 to the tank and it came rught back to 1.0 dam. Now today l did a WOT at 2 and 3rd gear and immediately dam dropped to 0.85 and had feedback knock and fine knock learn at about 2.81. Few minutes later dam dropped to 0.68. Is it possible this is just fuel again or what can it be? Should l accept it to go back to 1.0 dam? Any advice? I am running cobb stage 1 tune and muffler delete besides that its all stock.

 

So l had a dam drop before to 0.68 and l simply reset the ecu and added few gallons of e85 to the tank and it came right back to 1.0 dam. Now today l did a WOT at 2 and 3rd gear and immediately dam dropped to 0.85 and had feedback knock and fine knock learn at about 2.81. Few minutes later dam dropped to 0.68. Is it possible this is just fuel again or what can it be? Should l expect it to go back to 1.0 dam? Any advice? I am running cobb stage 1 tune and muffler delete besides that its all stock.

 

The COBB OTS tunes are VERY VERY conservative safe tunes that won't knock unless you give it poor quality fuel. My guess is that you got some bad gas.

 

But l have been driving on that tank for the last 200 miles and dam was at 1.0 and after wot it dropped right away. Im using shell 91

 

Why are you putting e85 in it?

 

I used 2-3 gallons of e85 to a full tank of 91 gas. Im in California l dont have 93 octane. Yesterday my dam when up from 6.25 to 6.85 with positive FKL

 

Can you PLEASE stop making new threads on the exact same topic? I'm going to start deleting your threads if you continue to do this.

This is the third thread of yours I've merged and my final warning.