Alex41

iTrader: (14)

so I'll try my best. I have a 00 TA that has been slightly upgraded with 3.42 gears, built trans w/2300-2800 Dacco stall, K&N filter, gutted cats, flowmaster muffler, supporting tune, and a bunch of suspension stuff.

My issue is when I roll into the gas in the mornings to just get into traffic it falls on its face. There isn't a miss nor are there any lights but it feels like fuel cut. I press on the gas and it just sputters trying to get up to speed. There are times when it warms up even that I will kick it down into passing gear and it will go fine but still studder while pulling, almost like its loosing signal from something and coming back on line. It really doesn't pull very well for what's been done to top it all off.

I have already replaced spark plugs, checked fuel pressure while driving and replicating the issue, used a known good TPS sensor with no change, replaced broken pcv hoses, replaced fuel filter, and a bunch of other checking.

It hasn't thrown any codes for anything but the tuner took some misfire parameters out in preperation for a cam swap soon. I'm at my wits end here and just can't find the problem. The other issue is I know I need to data log it but there is no one close to me that can do it and I can't drive it distances to go to my tuner since all of this crap knocks my car out of 4th gear once I hit closed loop. Please help.

joecar

Maybe clean the MAF sensor.

poseidon

My car also does this sometime when i try and give it a little gas. I just mess with the tps wires and then it stops. In your case idk.

Alex41

iTrader: (14)

Forgot to mention that I already de-screened the MAF.

LS6427

iTrader: (2)

If you're not going WOT when this stumbling happens, its not the MAF. But depending on your coolant temp the MAF can be in play while you're getting these issues. So defintely clean it.

Other than that, you need a scan to see how your 02 sensors are switching while the engine is running. A failing 02 sensor will cause partial throttle stumbling and power loss. And NO....you will not get a code/SES light until its totally failed or the engine is running terrible.

Have you been using more gas lately?

.

samson_420

iTrader: (1)

Hmmmm, try to swap to a OEM MAF, maybe. . . .

wssix99

iTrader: (5)

Maybe you damaged the MAF when you descreened it? Did you clean it also? This sounds like a classic MAF problem. Not sure if the extra fraction of a horsepower is worth risking a $350 sensor - its definitely not on my car!

Can you scan the MAF to see what kind of readings are coming from it?

What kind of air filter are you running?

Alex41

iTrader: (14)

Also forgot that I put new front O2 sensors in it. It has a K&N filter.

I know this problem persisted when the previous owner had it so it's not me damaging the MAF. It may have been bad before but I didn't do that to it.

I have only had the car for about 2 months so I really don't know if fuel consumption is up or down but I do know my gauge is very irratic and wrong. It was on E and telling me to check gauges and all I could put in was 11.7 gallons.

My biggest issue is that I can't scan the computer. I don't have anyone close to me with the software and I can't go to my tuner since he's on the other side of town and I loose 4th in closed loop. It didn't do that with the old trans but this new "built" one I bought seems to go away but will get 4th back after the car sits long enough to return to open loop.

I'm really about to end it all with this car and light the pig on fire here. I'm in a catch 22 where I know I need a scanner to read real time parameters but I can't get there to have it done. FML

LS6427

iTrader: (2)

K&N air filters are garbage dude. Get a paper filter. Often, actually all the damn time, the oil from the filter gets on the MAF and that makes the engine ran like ****. Try spraying the MAF with MAF cleaner and go for a drive. Again though, the MAF is only used for cold start and WOT runs. But do it anyway. And throw that K&N in the garbage. Paper filters cannot be beat.

.

bobbyd

iTrader: (10)

clean maf
clean throttle body
check spark plugs/wires make sure they arent loose.
does this happend all the time at a certain speed/gear? if so possibly a dead spot that i believe all a4 cars face.

my SS has a dead spot between 50-60mph. it will basictly feel like it losses power/falls on its face a little. if you go wot though it runs perfect

bobbyd

iTrader: (10)

you can also check the pcv valve and hose to make sure you dont have a vacuum leak

Alex41

iTrader: (14)

Did a ton today. We swapped in a known good MAF, removed the intake to see if the gaskets were bad (they were flat), cleaned the throtle body, removed the already turned off EGR pipe from the intake, and no change. I already replaced cracked pcv hosing and cleaned up that system.

Typicaly the serious studdering will happen in the morning when I take my son to school. It's not really cold here in San Antonio so weather isn't a factor. What happens is no matter how much I press the gas it revs up about 300 RPM's then falls flat on its face like it goes off line. The last time it did that it didn't clear up till I got it completely warm. That was a very isolated incedent.

What is really going on is while powering through gears it will just skip or stop for a split second on top of the fact that it just feels like its going up hill in 100 mile an hour head wind.

bobbyd

iTrader: (10)

next check the spark plugs and wires. also replace the fuel filer it might be clogged.

Duffster

iTrader: (103)

borrow/use HP Tuners and monitor the reactions. Best if you have a wideband bung added.

wssix99

iTrader: (5)

+1 on the fuel filter. It sounds like the fuel is getting cut off. (When the MAF is dirty, the PCM will command this to happen but since you switched the MAF, you can probably rule this out.)

Alex41

iTrader: (14)

Fuel filter is new.

1996firebirdformula

iTrader: (3)

Yeah could be fouled plug or wire messed up.

wssix99

iTrader: (5)

Maybe have your pressure checked and see if the fuel pump is doing its job.

Alex41

iTrader: (14)

Used a fuel gauge and drove it while it was taped to the windshield. I had 60+ PSI while driving and when it did its thing, it only fell 4-5 PSI.

Today I finally installed my Pacesetter headers and ORY. I made my own catback system out of the left over piping and made something that resembles the Loudmouth system. I have 2 bullets in the back right before my tips.

We talked about the possibility of the gutted cats causing some reversion in the exhaust Saturday night so I figured it was time to go ahead with the header swap that's been waiting for 3 weeks.

Sadly, that didn't fix it either. When I took the plugs out I did notice they were kinda powdery white so I'm thinking I'm getting starved for fuel. What would cause good PSI at the rail but poor fuel delivery to the engine?

ccrook19

fuel injectors possibly pluged up??