Sputtering Probelms!!!

[TSIGuy510]

hey guys i have a 90 tsi with a 14b, supra fuel pump, stock injectors, halman pro bc, dejon tool upper pipes, safc, turbo timer, cat back exaust, k&n filter, new plugs and wires, ungapped thoe wasnt sure if i needed to . well when i first got the car it was boosting around 18-20psi which is to much i know. It felt like i would hit a a wall when i boosted really hard. my freind said he thinks i was knocking really bad, so i turned it down to about 16-17ish and i took out the screw on the MAF so it gets a little better air flow thinking that might help. well now it doesnt feel like it hits a wall anymore, it just sputters after about 3800 and has no power and jsut sputters the whole way and wont rev high at all...so does anyone have any idea what its doing? i was thinking it seems like its running lean or something...he also said i could try to adjust the crank angle sensor back more to change the timing and i tryed doign that but it wouldnt go back anymore, its theres still more room for it to slide but it just wont move back....itll move down but not up....so idk what thats about either....any advice would help alot....thanks in advance....oh!!! and my safc is zeroed out cause i cant figure out how to tune it and it doesnt seem to help anything....so i didnt bother....

 

[the_mork]

You took the screw entirely out? You need to put it back in and you shouldn't have touched it at all without being prepared to start tuning. Are the honeycombs still in the MAF? If not put them back in.

You also shouldn't mess with the CAS. You now need to re-time your car.

The problem is that the MAF is used to actually read how much air is coming into the engine and is precisely calibrated to its shape and innards. Those honeycombs affect airflow and so does the screw which is actually the adjustment knob to make sure that the calibration is right between different individual units. Screwing with any of those bits will make your car run like crap if you don't tune for them. Most likely you need to add a bit of fuel with the SAFC.

 

[Trav83]

Yeah, you don't just move a CAS around and hope for the best, that's there to set your ignition timing! and even if you do wanna change your ignition timing (which I highly doubt is your problem) you have to do it with a timing light before you move the CAS. Now you need to set it back to 5 degrees

 

[TSIGuy510]

You took the screw entirely out? You need to put it back in and you shouldn't have touched it at all without being prepared to start tuning. Are the honeycombs still in the MAF? If not put them back in.

You also shouldn't mess with the CAS. You now need to re-time your car.

The problem is that the MAF is used to actually read how much air is coming into the engine and is precisely calibrated to its shape and innards. Those honeycombs affect airflow and so does the screw which is actually the adjustment knob to make sure that the calibration is right between different individual units. Screwing with any of those bits will make your car run like crap if you don't tune for them. Most likely you need to add a bit of fuel with the SAFC.

there are no honey combs in the bottom one, and all i did was turn it out not take it out so its still in there....so i should just turn the screw back in to about where it was? and i marked where the CAS was and i put it back in the orginal place so i didnt really even adjust it i just tryed . why would i need to retime it? and how do i add fuel with my safc?

 

[the_mork]

Put the screw back to about where it was if at all possible, if you have the lower honeycomb then put it back in.

You'll need to re-time because you messed with the CAS, base timing is very important and the ecu advances or retards the ignition from there, it doesn't matter if it seemed like it moved you'll still need to time the car, this is very possibly directly related to your continuing problems.

Add fuel with the SAFC by adding to your curve in the positive direction. You will need to do a lot of reading to understand how to use your SAFC and you should probably get a wideband o2 meter.

Also, stop listening to your friend, he appears to provide some misinformation. It is worthwhile to check any suggestions he makes on this board to make sure they are sane.

 

[dsmfa9nutter]

Set your timing and get an fpr for all the extra fuel you're dumping into your motor with the supra pump that's causing your breakup.

 

[Lofer]

Boost leak test?

 

[TSIGuy510]

Set your timing and get an fpr for all the extra fuel you're dumping into your motor with the supra pump that's causing your breakup.

thats another issue, i have no money .....but i will put the screw back in to about where it was, i dont think i have any leaks, i always holds boost well and i have the dejon pipes so im pretty sure thats ok, or at least not bad enough to affect this. ill keep the boost at like 16 and turn the screw in tune the safc up?

 

[the_mork]

You forgot set your timing, it doesn't matter if it is marked it is probably still off. A boost leak test is a good idea too and extremely cheap. Just because you can't tell doesn't mean it isn't happening. I had an issue with a TB gasket that was so bad that I couldn't get boost above 0 with my compressor set at 70psi. The car still ran but it was sloppy and it still boosted. Smaller leaks have let out an astounding amount of air and not noticeably affected normal driving at all.

 

[jeffo]

One thing no one has mentioned is MAS overrun. The 1G MAS typically begins to overrun, giving false readings, at 17-18psi. Removing the lower honeycomb mainly affects the idle, and only gives you another 2% airflow before overrun. You are also running dangerously lean for your poor Cali 91 gas with that much boost, IMHO. You should get an injector upgrade and dump the 1G MAS for a better 2G or 3G/EVO MAS, so you can safely boost 18+psi.
EVO 560cc injectors are available cheap, and the good 3G #482 MAS is the same diameter as the 1G aircan, so it bolts right in. It has less pressure drop than a 1G or 2G MAS, and is good for ~500 HP. You *WILL* need a chip to compensate for the MAS and injectors though. Contact me offline for more info.

 

[TSIGuy510]

One thing no one has mentioned is MAS overrun. The 1G MAS typically begins to overrun, giving false readings, at 17-18psi. Removing the lower honeycomb mainly affects the idle, and only gives you another 2% airflow before overrun. You are also running dangerously lean for your poor Cali 91 gas with that much boost, IMHO. You should get an injector upgrade and dump the 1G MAS for a better 2G or 3G/EVO MAS, so you can safely boost 18+psi.
EVO 560cc injectors are available cheap, and the good 3G #482 MAS is the same diameter as the 1G aircan, so it bolts right in. It has less pressure drop than a 1G or 2G MAS, and is good for ~500 HP. You *WILL* need a chip to compensate for the MAS and injectors though. Contact me offline for more info.

i have no money, like i said before and i dont have a compressor.....and one of the throttle body gaskets is new, got it with my piping kit. thanks for the info on the mafs thoe and injectors....how much would all that cost to do?

 

[talonawd4g63]

Do you know when your fuel filter was changed last or the filter in the tank on the fuel pump, I went through the same except mine would sputter at 4 grand around 10 psi. Changed both filters and car ran great. When you get some money you definetly need to buy a fpr for the supra pump.

 

[rocafellafw]

Sounds kinda like the problem I was having with my knock sensor. My sensor was bad and it was pulling timing under WOT and making me break up and sputter. Take a look at ## knock sensor and looking for oil and gunk all over it, if there is replace it. Also do the above mentioned boost leaks tests, plugs, wires, 2g MAF, and a FPR to control the supra fuel pump.

 

[TSIGuy510]

Do you know when your fuel filter was changed last or the filter in the tank on the fuel pump, I went through the same except mine would sputter at 4 grand around 10 psi. Changed both filters and car ran great. When you get some money you definetly need to buy a fpr for the supra pump.

thats what mine does!!! where do you get a fuel filter?

 

[TSIGuy510]

Sounds kinda like the problem I was having with my knock sensor. My sensor was bad and it was pulling timing under WOT and making me break up and sputter. Take a look at ## knock sensor and looking for oil and gunk all over it, if there is replace it. Also do the above mentioned boost leaks tests, plugs, wires, 2g MAF, and a FPR to control the supra fuel pump.

wheres the knock sensor? its a talon theres oil everywhere

 

[rocafellafw]

wheres the knock sensor? its a talon theres oil everywhere

true ok. The knock sensor is on the back of the block under the intake manifold, feel around for the sensor it's a hard metal round thing. I used a camera with flash to get a good view of it to see if it looked bad so I just reached down back there and took a pic. The best way to get to it/replace it is under the car between the axle, I forget the wrench size But I know it's big as hell

 

[TSIGuy510]

couldnt be as big at the 5 gear syncro nut ....it was huge q

 

[gsx7707]

you need more fuel and some kind of fuel management.

 

[trevnasty]

thats what i had to do now my car is running right got to have all fuel upgrades before you put them on just cant buy injectors,fuel pump and not the fpr they all have to work together to work right. good luck

 

[kmj 4g63t]

i had almost the same problem and it ended up being my maf. try finding someone else who has the same maf and test it. i was going nuts and it worked for me. btw your talon looks mint!!!!!!!!!!

 

[dsmfa9nutter]

I forget the wrench size But I know it's big as hell

15/16th

The usual way to get to it on a dsm is to pull the battery and go from the passenger side.

 

[jeffo]

i have no money, ....how much would all that cost to do?

A LOT depends on whether or not you already have an EPROM ECU. You should check that first:
89-94 EPROM Check

 

[TSIGuy510]

i had almost the same problem and it ended up being my maf. try finding someone else who has the same maf and test it. i was going nuts and it worked for me. btw your talon looks mint!!!!!!!!!!

hahah thanks man if i had the money i would def. do all the fuel upgrades.....but i dont so i gotta work with what i have for now....