first let me lis my mods
1990 tsi awd, fully hacked can, k&n filter, lower comb removed, 2g exhaust mani, 2 1/2" turbo back exhaust w/test pipe, 255 pump (not rewired), curently running 15psi boost.
I've done my research on this topic but every situation is different. I am just wondering if there is any method to fix the fuel cut aside from turning down the boost, keep in mind I have no money. I have checked for leaks and have found none any other suggestions would be appreciated. I apoligise in advance if this very same question has come up but I did many searches and didn't find what I needed.

sorry I forgot to mention that the cut pronounces itself at 5700-6000rpms in second gear

Are you sure its fuel cut? Does it feel like your hitting a BRICK WALL?? Or does it just hesitate and kind of quit for a second. If it doesnt feel like your hitting a brick wall, its probably just bad wires and plugs.

its like a back fire and all power is gone for a second fairly violent not like hitting a brick wall though. New accel wires and bpr7es plugs. I didnt have this problem until I installed my exhaust like a week ago but its hard to tell if its that or the colder air??

I dont think its fuel cut then cause it is a very violent experience but I would rewire your pump just to be safe. Try another set of wires. Just cause they are new doesnt mean they arent sh!t. I can vouch for that.

Sounds like fuel cut to me. Colder air temperatures will promote it.

Adding more fuel will NOT fix your fuel cut problems.

<a href="http://members.shaw.ca/costall/1000Q/answers-problems.htm#howdoIpreventfuelcut">Read.</a>

Well I think Im going to hack the maf. Please reply if you think I should not but from what I've read its either that or get a afc(can't tho no $$).

If you get an AFC you need injectors too or else what's the point. See if you have an eprom ECU and get a TMO chip.

Sure, hack the MAF. Let us know when you're in the market for a new engine, it won't be long. :rolleyes:


An AFC, by itself, will not solve your fuel cut problem. If you're fortunate, it may delay it very slightly.

Hacking the MAS will not solve your problem. That's a solution for MAS overrun, not fuel cut. Hacking the MAS will delay fuel cut - a lot - but it will also make your car run very lean. Engine-destroying lean. You then need an AFC in order to fix the lean problem, which puts you right back where you were before.

Installing bigger injectors and an AFC will likely solve the problem. The bigger injectors will make you run rich. You can then lower the airflow signal with the AFC. Net result is you are running the same mixture as before, but with an airflow / airmass signal that is low enough to avoid hitting the fuel cut threshold. You hope.

However, the only ways to eliminate fuel cut completely are a TMO-type chip, or a DSMlink. DSMlink is not really an option for you, since you're a 1G plus you're broke. That leaves the TMO. Fortunately for you, TMO knockoff copies can be had on eBay for cheap, and your ECU (being a 1990) almost certainly has the required EPROM in it.

thanks for the info guys I'll post when I have figured out what I'm going to do

Jordan, I posted a couple of weeks ago about this exact problem, as did other people. I just fixed my problem yesterday but it may not apply in your 1g. My problem was my o2 sensor housing to downpipe gasket. It was leaking very badly to the point that it sounded like crap. 2gs have an o2 sensor on the exhaust that is after the cat. Under 18lbs of boost there would be a lot of air escaping through the gasket. Air that is not counted by the second sensor. I put in a new gasket and voila! No sputtering! My EGTs are still high but that is another problem. Cold air, not enough fuel = LEAN.

And 1Gs do not.

Jordan

I had the same problem, I followed some inscructions from the site(hacking themaf bleeder screwetc.), I'm running 15 psi with a stock pump its been a year very reliable could be sheer luck.

Removing the stock honeycomb filter and backing out the adjustment screw is not "hacking the MAF". If you haven't taken a Dremel or air grinder and cut in to it you haven't hacked it at all.

[edit: formatting]

If you hack the maf you'll need at least the pot mod http://www.ecanfix.com/~mdhamilton/fuelmod.html
Not sure if this will cure your fuel cut once you tune it back to a proper mixture again, but at least you have some tuning ability and aren't running way lean. I'd say get a logger though to really know what's going on and make sure you're not running lean. Knock led won't tell you anything cause pre-fuel cut will make it blink even when there's no knock (that's what I get).

If you have a logger all you need to do is get something like a b&m rising rate fuel pressure regulator (or a c-clamp on your fuel return line ), then add fuel and hack the maf (and/or tune the pots if the ecu cares) to delay fuel cut. You can probly get a b&m for not much over 50 bucks.

Basically what you want to do is make the ecu see less airflow, while you compensate with more fuel. If you just make the ecu see less airflow (hack the maf) you'll run lean. That's it.

Won't do anything for fuel cut, unfortunately. Fuel cut is based on air mass, not air flow. If you reduce the air flow signal and "make up" for it with the temperature signal mod, the ECU will "see" the same total air mass.

Of course, you could lean it out slightly and delay fuel cut - slightly.

The adjustable regulator is a good one I forgot about. However, the 255 (depending on the model) might already be overrunning the stock regulator. Ideally, you may want an adjustable FPR that allows you to turn *down* the fuel pressure - and they're more expensive.

You could just turn your boost down a few pounds for the winter.

Yeah the rewire would be a bad idea for the 255 cause it will most likely start overrunning the regulator if it's not already, and it will cause more problems than it will solve. Rewire is only useful if the pump is running out of breath at high revs, which the 255 will not.

What I'm saying is if he's got the fuel flow, he'll be able to lean her out with the pots or hack the maf more. Pots are nice for fine-tuning still, as I mentioned. So either he has the fuel now because of the 255 and can just lean it out as is, or he'll need to up the pressure to get the extra fuel. Either way he needs a logger to be sure.

Second, and I'm not 100% on this, I think upping the pressure will help things even if he's overrunning already. This stands on the assumption that the fpr will maintain the set pressure and not cause more overflow at a higher pressure setting. Theoretically it shouldn't.

Let's say you're overflowing at idle and get 45psi of base pressure instead of the stock 38. At higher rpms the pressure will level off at 38. Well things get complicated by the boost reference (subtract with vacuum, add with boost), but I think we can talk of a theoretical "base" pressure which should be constant, but is not constant when you have overrun.

Now if you set your base pressure to 45psi, you'd get the same 45psi from idle on up to redline, making tuning nice and easy. You can lean it out evenly across the board and delay fuel cut.

Somebody correct me if you have experience to the contrary.

You may be correct. Unfortunately I've never seen anyone confirm or deny that the 255HP overruns an aftermarket FPR as well as a stock FPR.

Also unfortunately, he's broke and probably can't afford a logger either.