Recently, I just added my electronic dump valve and readjusted my MBC to be set at 22psi, tapering to about 21.5psi at redline. Everything in this post refers to the dump valve being open. While driving in 4th gear, at WOT, the service engine soon light will flash for a millisecond and go away... when this happens, the car sputters and hesitates for a fraction of a second, and I let off the gas. It does not happen all the time either, just random... sometimes I can WOT all into 5th with no problem.

One time, I pushed it at WOT with the service engine light flashing a couple of times but kept it at WOT... afterwards, 5th gear began to grind everytime I tried to shift into it. I immediately got off at the next exit and turned off the car at a gas station. My turbo timer failed to work. I tried many times, with adjusting the TT, and it would not time down my car. After turning off the car and turning it back on, the service engine light stayed permanently on and would not go away. I drove the car for another 10 minutes to the nearest AutoZone to have the code pulled. During the drive, 5th gear never grinded anymore. After reaching AutoZone, when I turned off the car, the turbo timer began to function again.

The code pulled was "P0102: Volume Airflow Circuit Low Input"

I reset my ECU, and the service engine light has never come on permanently again. I lowered the boost to 21psi and to hold 20.5 'til redline. The car still randomly will hesitate and sputter @ WOT in 4th and make the service engine soon light flash for a millisecond. The grinding 5th gear problem has reoccured only one more time, and it was after WOT in 4th with the SES light flashing... but stopped grinding a minute later.

My turbo timer is HKS and installed with the 2g dsm/evo wiring harness.

Anyone know what my problem could be? Any info would help... ask any questions if you need more info!

 

Hmmmm... fuel cut? Just my thoughts.

 

I've hit fuel cut before, and it feels like I just crashed into a brick wall (from WOT)... however, this feeling is more like a very very slight hesitation/sputter... like a hiccup. I'm assuming it might be a misfire, but I can only assume with nothing to back it up.

 

Turbo timer is not installed correctly, which is obvious.
Sounds like it has a bad connection somewhere and it very likely is contributing to the cutting out.

 

Turbo timer was installed perfectly, just like anyone else's TT's... so I don't believe any of the wiring is contributing to this problem.

 

I think it all has to do with your O2 sensor that is bypassed. Just my .02

 

sorry to thread jack but what does tt mean?

 

Misfire maybe? Any code afterward?

 

Everytime the SES light flashes for a millisecond, it never stays on permanently anymore, so there's no way to check for any code.

y the way,

TT = Turbo Timer
SES = Service Engine Light
CEL = Check Engine Light

 

Does the SES flash continuiously for a time period of 3-5 seconds, or just a quick flash and gone? I don't know the answer to the latter, but if it's what I said in the first part of the question, then I'm pretty sure it's a misfire.

 

If I stay on WOT, it'll flash on/off continuously for a couple of seconds... it'll flash maybe 3-4 times really quick and sputter if I keep it on WOT...

Any idea why it might be misfiring, if it is? This has never happened until I got my electronic dump valve... and only happens with the dump valve open... maybe spark plugs need to be changed? Hmm...

 

Okay lets review. Car cuts out, which will cause SES light to flash. Turbo timer stops working because of one of 2 things. It either lost it's RPM signal so it can not auto adjust or the TT lost it's constant power from the ignition.
Any poor connection at the harness to the ignition can cause problems such as this. How is the RPM signal tapped at the ECU? If I remember correctly the TT comes with those ****ty *** clip on wire taps. If so then look no further. They cut through the insulation to make a connection. Problem is they can also cut into the wire strands.

 

Electronic dump valve? Never heard of it, maybe if you could send me a link to it, I can see what the problem is.

 

I bet it only does it when the dump valve is open right??

Car is really loud at that RPM too, right?

If this is the case then you may possibly be suffering from exhaust resonation (since the outlet is now very close) causing the MAF to alter it's signal.

And now that I am thinking of it, you don't have anything on the back side of the valve to control flow so all the sound waves are allowed to bounce off anything the want. A downturn pipe would probably make a big difference.

 

That makes a good point, I read about our car's MAF signals being altered due to just vibrations from other people's exhausts...

However, why does this only happen on WOT in 4th (sometimes) and 3rd (rarely) and 5th (rarely) but never in 1st and 2nd? ... it's just as loud in those gears at WOT as it is in 3rd, 4th, and 5th. Also, why does it only happen sometimes and not everytime? I know you might not be able to answer all my questions, but I'm looking for all the info possible.

As far as the TT goes, the voltage meter and power to the TT functioned perfectly fine during the period it wouldn't time down the car. I always used a 1.5 min timer on manual setting and it always worked... just for those few minutes, it wouldn't time down... but the TT itself never lost power and the voltage meter always read correctly.

Thanks so far people with the responses and help.