09TcSedan

so my buddy has an 08 SS/TC. intake injen,cold side pipe-injen,catch can,custom turbo back exhaust.

last summer he got it tuned by a local shop,it only layed down like 275WHP. which was kind of odd to me,maybe the local shop didnt know what they were doing.

so EARLY this spring he went on a 100% E-85 Trifecta tune. last weekend at a dyno day he only layed down 305WHP/321 Torque. another balt with i believe similar mods and E85/trifecta tune layed down 339/351TQ.

hes been blowing through MAF (the one in the intake manifold) sensors. hes on his 3rd one now.

he switched from E-85 back to 93 today.

when he was on E-85 he would spin in second.

just wondering if anyone could think of why he has been tuned twice and is hitting such low numbers on the dyno?

padlock

iTrader: (9)

what kind of dyno?

BPacak

doesnt matter what kind of dyno he should have been able to put down more than that.

09TcSedan

i forget the name of the dyno.
thats what im sayin and a couple buddies of mine who drive cobalts. it seems super low for the given mods and a trifecta tune.

ItalianJoe1

iTrader: (10)

How does the car run compared to the similar cobalts? Does it seem like it's down 40hp?

BPacak

i ran mine on a mustang dyno which reads lower than a dynojet and i still put down 300+ with a trifecta tune.

brycerice13

Whenever you have an intake you must calibrate the maf sensor, if its not calibrated it will make your fuel trims off and could effect the tune also. If the tuning shop did not know what they were doing they probably did not calibrate the maf.

SSlobalt

Go read Matt's thread about "May I have a retune, please?" There's something wrong with the car. The best place to start is codes. Get the ECM read for DTC's. If it has none, I will be surprised. Bring the codes back here and get some opinions. Next, do a boost leak test. Find all the leaks and plug 'em.

If he had MAF sensor errors before, they might have been caused by a boost leak. If he actually is frying the MAF sensors, it would have to be the connector/wiring, or he has a metal intake tube that the MAF is grounding on.

09TcSedan

I think it was a dyno jet. I havent ran him in my cobalt but my other buddy who had exhaust, intake, ported intake mani and the Hahn tuner was layin down 335/360 TQ. Now my buddy who im talking about with a trifecta E85 tune has the mpz intercooler also. Ill have him scan his car for codes and see if he has done a boost leak test

SSlobalt

The purge solenoid is here:



Replace it with a new part. It's only $32. When it sticks open, this will cause a vac leak and made your car run like poop.

Do you have soldered-in 3-bar MAP sensors?

marks08

no i dont have a 3 bar map sensor. thyank you im going to try that silenoid. looks like an easy enough replacement. lol

Knightwolf

Hmm... interesting.. sub'd

SSlobalt

Yeah, it takes about 5 minutes. It's almost like they knew it would be a problem. I don't know what to tell you about going through so many MAP's. If they're oily, get a catch can.

marks08

i have a catch can. lol mpx. the cel code is p0496 evaporative emission system- High purge Flow

RobSSsedan

I changed my Evap Solenoid about 1 month ago I bought it on Ebay for $10 extremely fast shipping. lol

GM Pontiac Buick 12608378 Vapor Canister Purge Valve, Same as ACDelco 214-2125 | eBay

I had a P0455 code.

I found a Youtube vid on how to test the Solenoid.

DDMWorks - EVAP Solenoid Testing and Replacement on Ecotec engines - YouTube

09TcSedan

Thats votta be the evap selenoid!

marks08

silinoid is bad i did the test, and there is a small crack in the plastic hose. can i replace it with a rubber one?

SSlobalt

I assume it's plastic for a reason. It has to be a material that is compatible with gas fumes. I don't know how far that tube goes, because I've never looked, but it can't be very expensive.