fuel cut stock turbo stock boost

[nickk90]

I just got my DSM 2 months ago. I was told he has a boost leak test done right before I bought it and it had no leaks.
It was running stock boost and on a cold night getting on it in 2nd gear I hit fuel cut. I got a RBoost.com boost controller and have it set at 15psi and now almost every time I get on it in 2nd gear I hit fuel cut. If I ease into the gas it doesn't happen but if I just step on it in 2nd I will. A friend told me to hack the MAF. Is that a good idea?


It is fuel cut for sure. The first time it happened I thought blew up my engine.

My car smells really rich also and I always get little specs of carbon on my bumper witch is making me think i actually am running rich and im not just thinking i am because of the smell.

 

[gusu]

Eh, hacking the MAF has both good and bad sides to it but I mostly hear about the bad.

Have you checked everything with your fuel system even down to the filter?

My friends eclipse used to hit fuel cut on cold days until he got a new filter but then again on cold days your fuel is harder to push.

You might also want to check to see if your fuel pump is going bad or if your injectors are getting clogged even if they are not the issue it is still nice to make sure everything is properly maintained.

 

[constant_proj21]

Did you just take the guys word for it, or have you actually done a boost leak test yourself?

 

[Codester]

I test mine weekly for boost leaks. Its just a regular thing I do with checking oil level and what not. Just get the boostpro tester and a reducer coupler and do it yourself. I used to go to the gas station and use the free air to do my tests for a while til I finally said screw it and bought an air compressor.

 

[nickk90]

He always took it to a shop for everything and had the the papers for it, they replaced the BOV diaphragm at the same time. I am going to get the boostpro tester with my next pay check and do a boost leak test myself.

And about the fuel system, I thought that fuel cut has nothing to do with your fuel system it is triggered by the MAF and nothing else?

Is there any chance a dirty MAF could be adding to the problem because who ever cleaned the filter last used a ton of oil on it?

Last night I was out having fun in her and didn't have a problem. It warm out though and I made sure I eased into 2nd.

It always happens in the same spot too. There is a road around the corner from me that has a nice smooth downhill left onto it then its completely flat and straight for about a mile and it always happens when i gun it out of that turn and Ive never had it happen anywhere else. pretty weird but the air is super dense around there because its in a valley i guess.

 

[slowboy101]

Yea I would say just do a boost leak your self just to make sure cause you cant always take peoples words. Other wise just get a 255 fuel pump there only 100bucks and are really easy to install.

 

[90gst_sean]

Fuel cut can be caused by to small of injector or running out of pump, but on stock boost this is not likely the case -unless you are losing fuel pressure somewhere. I'm thinking boost leek.

I'll leave this info for 1g guy's -- as this is a 2g car we're talking about and I know that now...
If you are in the market for a new 1g maf, you should check "Jacks Transmissions" Last I checked they had a lot of OEM part for super cheep. And I think I saw some 1g mafs for like $50.

I agree that you need to do a boost leek test ASAP. But, you don't have to buy a tool to test with from the net, you can make one from the hardware store just as good, and you'll have it today.

Good luck.

 

[Alex Bland]

Yea I would say just do a boost leak your self just to make sure cause you cant always take peoples words. Other wise just get a 255 fuel pump there only 100bucks and are really easy to install.

+ the money for afpr

 

[slowboy101]

^^^ true sorry for got to add that in there.

 

[nickk90]

ok im confused on what causes fuel cut now. Is it the fuel system or is it the MAF reading too that theirs too much air entering the engine?

90% of what Ive read has said fuel cut is cuased by the MAF, a few post i have seen has said its injector duty%.

 

[90gst_sean]

If you want to really get down to it, it is caused by the ecu.

If the 2g ECU reads a volumetric efficiency of over 200%, it will generate a detfault code of P1103, and remove fuel. This is fuel cut. (ECM Tuning)

Air/fuel ratio.

Air=maf and fuel=injector. When looking at a ratio, it doesnt really matter if you make one side bigger or the other side smaller; they both effect the ratio.

One person could say I'm sucking in to much air... and there for assume that his Maf is the cause of the fuel cut, and thats one way to look at it. But, someone else might look at the same set-up and say, you are sucking in to muck air... for your fuel system to support... therefore saying that that the true cause of the fuel cut it a lack of fuel; be the problem injector, pump or restriction.

I think you are looking at this from a boost leak stand point. If a stock DSM experiences fuel cut, I believe you would be right to assume that the maf is the cause -- because it is reading to much air, or to little air in the system.

 

[jrohner]

Fuel supply itself has NOTHING to do with fuel cut. Fuel cut is set in the ECU to happen at a certain airflow. The only way to not hit fuel cut is to remove/raise fuel cut (reflash the ECU), or make sure the ECU never sees that much air. You have a 99, so you can get an openport 2.0 cable and reflash the ECU; that would be the best and most efficient way to tune.

 

[ramsack]

Fuel supply itself has NOTHING to do with fuel cut. Fuel cut is set in the ECU to happen at a certain airflow. The only way to not hit fuel cut is to remove/raise fuel cut (reflash the ECU), or make sure the ECU never sees that much air.

Thank you. I have seen so many threads lately where people suggest upgrading the fuel system to get rid of fuel cut. And to those I ask, how does the ECU know that you have upgraded your injectors or pump? It can't possibly. There is plenty of info to read on how fuel cut works.

 

[turbo_lag92]

def sounds more like a boost leak to me. i would check all couplers, bov, throttlebody, j pipe gasket

 

[JayRolla]

The ecu don't care what fuel injector u have. If u run out of injector the car runs lean. It will not cut the fuel. It cuts fuel when the maf is overrun plain and simple. Boost leak is 99% usually the reason for fuel cut.