fuel cut issue???

N8THEGR8 · Mar 24, 2008, 06:08 PM

so i put the ap and tbe on last week. IT is awesome so far but what i have found is when i try to turn the boost to 21psi like it says, i believe there is a fuel cut issue around 5500-6000rpm. Now i know it is suppose to taper to around 19psi around redline but is that what is causing possible fuel cut? Another thing is the motor doesn't sound as strong as i think, now i know this could be in my head and i hope it is, but could there be something else going on hear? any suggestions would be greatful. tnks

Davedangerous · Mar 24, 2008, 07:17 PM

you're mostly likely getting fuel cut. I've experienced it today for the 3rd time. What you're feeling is probably the smoother power curve. My advice is to get protuned.

N8THEGR8 · Mar 25, 2008, 08:30 PM

i just got the program and don't want to dump any more money in a protune. I don't have any other mods that support paying the money for it at this time. is there anything else that could be going on? Is it possible the car has cams? I bought it from a car lot so i don't know if it had a flash or anyhting. i know there was a boost controller of some sort and another gauge was on the steering column at on time. i had fuel cut today again after i turned the boost down to .14mpa or 20.3psi. I don't get what going on here but its becoming very frustrating.

Davedangerous · Mar 25, 2008, 09:25 PM

You should contact christian @ cobb, or your nearest AP tuner about the issues your having. The AP controls boost on its own and its really not necessary to have a mbc. I'm not sure how to correct your issue with a mbc.

*edit-> make sure you're running the latest map from cobb, check out their site

N8THEGR8 · Mar 26, 2008, 09:21 AM

thanks, i kind of feel like an idiot cause i was looking at other threads and there are more people having the same problem (i.e. i didn't search first). i am going to call them and look at the site.

CDO · Mar 26, 2008, 08:47 PM

It could be your boost gauge reads low so you're actually raising the boost too high.

Just in case this has nothing to do with the AP or your MBC, do you have the stock airbox on? There's been a few posts over the years of people experiencing what you described and it turned out the 2 screws that hold the airbox in place were missing and the airbox would lift up and choke off the incoming air. I believe it was right around that rpm.

RandomDj · Mar 26, 2008, 09:44 PM

wait... i don't quite understand your situation... what are you using to 'turn down' your boost? the AP uses the stock solenoid and controls boost via the ecu...

TheEvolutioner · Mar 27, 2008, 08:19 AM

Whats happening is your boost is shooting way too high during those rpm range (5k-6k). The ECU automatically cuts full when it reaches 26PSI. You might be spiking to 26PSI and thats when you feel the boost cut/ fuel cut (like hitting a brick wall). Sometimes it will throw the code for OVERBOOST CONDITION and sometimes it won't. I have gone through this so many times, i've contacted Christian and he sent me a new map twice and it still does it. I beleive it does it more since its cold weather. What you will need to eliminate this issue is a pro-tune. I'm hopeing once the warmer weather comes that this boost cut at least goes away.

philevo · Mar 27, 2008, 08:48 AM

You need a pro-tune. The same thing happened to me.

CDO · Mar 27, 2008, 08:59 AM

Quote:

Originally Posted by TheEvolutioner

I have gone through this so many times, i've contacted Christian and he sent me a new map twice and it still does it. I beleive it does it more since its cold weather. What you will need to eliminate this issue is a pro-tune. I'm hopeing once the warmer weather comes that this boost cut at least goes away.

I don't know in these cases if it's the car's or AP's fault, but if you need a pro-tune to get the car to work properly with the AP, I'd say it's time to ditch the AP.

I live in a northern state and drive with my foot to the floor and have never experienced this problem. It must be a *****. The highest boost (spike) my car has seen is 23.5 with the AP and 20.5 without.

CPA5 · Mar 27, 2008, 01:41 PM

Quote:

Originally Posted by TheEvolutioner

Whats happening is your boost is shooting way too high during those rpm range (5k-6k). The ECU automatically cuts full when it reaches 26PSI. You might be spiking to 26PSI and thats when you feel the boost cut/ fuel cut (like hitting a brick wall). Sometimes it will throw the code for OVERBOOST CONDITION and sometimes it won't. I have gone through this so many times, i've contacted Christian and he sent me a new map twice and it still does it. I beleive it does it more since its cold weather. What you will need to eliminate this issue is a pro-tune. I'm hopeing once the warmer weather comes that this boost cut at least goes away.

Bro--that sucks...I thought the map he sent you worked

What is up with you getting a tune out there?

CPA5 · Mar 27, 2008, 01:44 PM

Quote:

Originally Posted by CDO

I don't know in these cases if it's the car's or AP's fault, but if you need a pro-tune to get the car to work properly with the AP, I'd say it's time to ditch the AP.

I live in a northern state and drive with my foot to the floor and have never experienced this problem. It must be a *****. The highest boost (spike) my car has seen is 23.5 with the AP and 20.5 without.

My guess is that is has to have something to do with the values loaded into the base map that those guys are running.

I have never spiked higher that 23.5-8 over the winter time....then again I am using ecu to control and the cobb map is only supposed to hit 21.5psi......gotta love winter time.

Here it is we all keep telling everyone to get TUNED....and yet none of us can because either no one has a tuner near them or better yet the TUNING half of the software isn't even available to anyone.............IT seems like the only guy who has been successful at tuning evos with the AP has been Bryan from GST Motorsports........Lets all mob their place in San Fran and get Tuuuuunnnnnneeeeddd!!!!!!!

artisticspawn · Mar 27, 2008, 01:56 PM

Quote:

Originally Posted by CPA5

Here it is we all keep telling everyone to get TUNED....and yet none of us can because either no one has a tuner near them or better yet the TUNING half of the software isn't even available to anyone.............IT seems like the only guy who has been successful at tuning evos with the AP has been Bryan from GST Motorsports........Lets all mob their place in San Fran and get Tuuuuunnnnnneeeeddd!!!!!!!

I was thinking about purchasing the AP but it seems a little crazy to spend the money on the AP and then to go get pro-tuned. I have been reading about all the issues with the base map(s) and it is surprising to see how many people are stating that the solution is to get pro-tuned. I would think that for those people who want to simply stay with the bare minimum of alterations (TBE & AP), that this product should perform as stated and without the necessity to have to spend more $$ to get tuned.

Besides, those of us on the east coast will have a very hard time putting all those miles to make it to San Fran...

tk2481 · Mar 27, 2008, 05:43 PM

yea im on the east coast to but i have to say no probs with my base map. Just a couple knocks on the 93 map but i believe that was from crappy gas. It transformed my whole vehicle id spend 700 again anyday. Besides Street tuner should be coming out soon, I hope.

N8THEGR8 · Mar 27, 2008, 10:38 PM

Quote:

Originally Posted by CDO

It could be your boost gauge reads low so you're actually raising the boost too high.

Just in case this has nothing to do with the AP or your MBC, do you have the stock airbox on? There's been a few posts over the years of people experiencing what you described and it turned out the 2 screws that hold the airbox in place were missing and the airbox would lift up and choke off the incoming air. I believe it was right around that rpm.

no i have an aftermarket filter on my stock intake pipe.