sputter above 15 psi and knock plus cut out at 3500!

[92tsifwd]

I was wondering why my 1993 Eclipse Gst sputters at anything over 14-15 psi and it is almost like fuel cut exept no big jerk. If you know what floating valves sounds like on a older v8, it sounds similer to that. Also my car spikes to 19-20psi cuts out at 3500-5500 and settles to 15psi and then pulls hard to red line with all kinds of knock (32 counts and higher). All of this happens at 3500 and up There is no boost leaks. timing I believe is at 5* btdc base still. Is this fuel cut or somthing? Mods are

9to1 compression pistons
balance s/ removed and ud pulley, and ballance shaft sprokit lightened
jdm intake functioning and ported
2g mass (screens in) screw left alone
3" intake with k&n
2.5" uicp w/ 1g bov uncrushed
walbro 190lph (not rewired)
550cc injectors, Safc2 tuned decent
centerforce df with lsd
mbc
16g ported & ported exaust man
2" j pipe
2.5" turbo back exhaust with ext dump

02's were .85 all the way from 4000 and up and don't really change wether I add or take away fuel. knock was around 30-43 from 4000 and up!

 

[CanadianTSi]

Sounds like bad plugs/wires for the sputter and the cut out at 19-20psi would be fuel cut.

You need to get your knock under control.

 

[crunchymilk]

bad plugs/wires

get NGK BPR7ES and gap them at .028

regarding all that knock, start the tune all over, it sounds like it's too messed up to salvage. Reset everything and start again imo.

 

[92tsifwd]

bad plugs/wires

get NGK BPR7ES and gap them at .028

regarding all that knock, start the tune all over, it sounds like it's too messed up to salvage. Reset everything and start again imo.

Ok, I am -4% at 6000 and up on the safc2 if I remember. So if I remove the fps and run the vacume streit from the manifold to the fpr will it still fuel cut? I have ngk bpr7es plugs gaped at .028 already and they are fine and also accel thundersport wires wich might be about time to replace. It runs pretty good at part throttle. These problems only ocure under boost and wot. I am going to try using the ignition coil I had before this was hapening and see if that helps and also bypassing the stock fps. I did however rewire my 190lph pump and it runs richer but still spikes to 18psi cuts out and then pulls 15psi to red line with the same knock. I'll let you know after I try this stuff.

 

[92tsifwd]

I tried that and it didn't make any differance. But I have been able to tune quite a bit of the knock out by richening up high throttle. My settings now are knock is now about 5-10 counts. This just seems like alot of fuel with 550's and a rewired 190 pump. How do I get rid of this damn fuel cut? I did not think I would be hiting fuel cut so soon with the 2g mass. I need to get rid of this fuel cut fast. I checked base timing lat night and it was right but, I moved it to 4* btdc to see if it helped and it didn't.
high th
800 -5
1600 -3
2200 -3
3200 +4
4000 +7
4400 +9
5000 +9
5400 +9
6000 +10
6400 +10
7000 +9
7400 +9

low th

800 +2
1600 +7
2200 +15
3200 +13
4000+9
4400+9
5000+9
5400+9
6000+9
6400+9
7000+9
7400+9

 

[olmytsi]

Your afc settings are definitely weird. You should not have to add that much fuel.

 

[talonTSIDriver]

Your afc settings are definitely weird. You should not have to add that much fuel.

He may have to add fuel because he is running a bigger turbo and there is more CFM. Friend of mine is running close to the same setup with the big 16g and 550cc, and we tuned it with about +5 correction and some points.

I would change your plugs, wires because thats more than likely causing the stutter, and then re-tune the car.

 

[92tsifwd]

I dought it is that. How the hell is it fuel cuting so early though? This is defiitaly electrical. My other car with same mods only a front mount would not fuel cut until 30psi with 450's so why would it do it now with 550's and less mods?

 

[olmytsi]

The fuel cut is definitely due to your + settings in the afc. It is telling the ecu you have ALOT of airflow although you don't. Again, your settings should NOT be looking like that specially for the hi throttle maps.

 

[92tsifwd]

The fuel cut is definitely due to your + settings in the afc. It is telling the ecu you have ALOT of airflow although you don't. Again, your settings should NOT be looking like that specially for the hi throttle maps.

The corection factor was the same on the other car as this one exept this car has 550's and a side mount ic. It also did this with -7 across from 4000+rpms so I think it is just reading too much air flow period or mabey the mass needs replaced or somthing. Can you do anything to get rid of this fuel cut without buying a $275 eprom? Also why did it not do this with 450's and a higher corection factor? I know that my awd with 750cc injectors did this same thing until I made a custom eprom chip for it and got the compensation and deadtime dialed in. So is there a fuelcut defencer or somthing or do I have to spend $275 on a eprom and chip?

 

[olmytsi]

You do not need an eprom to get rid of fuel cut. You should not have fuel cut (aka your afc settings shouldn't be that far in the +) if those injectors are indeed 550s, and the rest of the fuel system is adequate. I could be wrong but i doubt it

 

[92tsifwd]

I think this is somthing else besides fuel cut because fuel cut I hit before and it feels like a brick wall came out of no where. This just pulls decent untill until 14psi then it feels like sombody removed about 50 horse till red line and cuts in and out along the way with loads of knock which that is probably mini fuel cut. I think I need to have these injectors corected in the ecu because my awd did the same thing after the 750's and when the eprom chip was put in it ran fine. Also my sidemount gets really hot even at 8psi and rich settings. Do you think it is maxing out the air flow in the ecu or hitting the airflow cap or somthing? It does not cut out at 13psi but, it makes no power and still gets 5-10 counts of knock. It pulled a hell of alot harder with 450's and had way less problems so mabey I should put them back in.

 

[1991gs-t]

First thing you defenatly need to do is change your plugs and wires. Trust me on this, its happened to me dozens of times. Then go and retune it. Problem will go away. Second that loss of power you feel is most likely timing being pulled from knock. take care of the plugs and wires and then things should go back to normal.

 

[92tsifwd]

First thing you defenatly need to do is change your plugs and wires. Trust me on this, its happened to me dozens of times. Then go and retune it. Problem will go away. Second that loss of power you feel is most likely timing being pulled from knock. take care of the plugs and wires and then things should go back to normal.

I forgot to say I put new wires on and it runs a tad bit smoother but still does it. The ngk bpr7es plugs look fine and are gaped right but, I will try puting in some new ones when I get some money. Why does my ic heatsoak so easy at 13 psi? I no it is hot outside but it gets pretty damn hot.

 

[Dred]

It's heatsoaking cause your EGT is very high due to knocking and timing being pulled. This was happening to me bout a week ago. What I did was retard that timing to about 2* BDTC but I had to do that because I had a few boost leaks. Their fixed now tho, so the main cause of my problem were the boost leaks I guess. Judging by your o2's youre getting rich knock, the o2's should be higher. With my boost leaks and running rich I was flatlightings to 0 w/ the o2 at WOT. I had the exact same problem, except my problem revolved around boost leaks, you're running rich for another reason if you did a leak test and didn't find anything.

 

[92tsifwd]

I zeroed out my safc2 all the way across and it actualy pulls to redline strong. Before the 550's I had +10% across on high thr above 3200 so, with 550's I should start out at -8% on high thr above 3200 right? Is this corect? Because I heard that 550's flow 18% more fuel than 450's. Is that true? The car runs very good with the safc zeroed out but I am sure it has more up top end so I am trying to get a good base tune. I think it was getting rich knock because it pulls pretty good now although I have not dataloged it yet with this tune.

 

[olmytsi]

"Baseline" for 550s is usually -20 ish across the board. However, every car is different. So, the best way to do it is to set it by watching your fuel trims (get them as close to 100 as possible). I told you the + settings was the problem
Glad you are making progress.

 

[92tsifwd]

what about with the 2g mass though? What should my settings be if they were +10 with the 450's? Now what should I start out at because, the 2g mass flows like 20% more air right. So it should almost cancel out? Anyone have this setup who can let me know what they ended up with for settings?

 

[92tsifwd]

I now have these settings:
th points are 40%low 80%high
low th

800 -3
1600-2
2200 +0
3200+2
4000+5
4400+5
5000+5
5400+5
6000+5
6400+5
7000+5
7400+5

High th
800 -10
1600-10
2200-8
3200-8
4000-8
4400-8
5000-8
5400-8
6000-8
6400-8
7000-9
7400-9

Are these decent settings for a 1g with 2g mass and 550's and fuel pump? I just tuned the way roadraceengineering.com said to lean it out until the o2 quits cycling and then add 10% to that rpm. is this corect? I am unsure on high throttle though because I am unable to get rid of this fake knock. By basicaly just adding 10% across I was able to reduce this knock quite a bit but you can tell the car is running un godly rich when doing this and hits fuel cut. I need to know what a good starting point is for my setup and if my curent settings are safe without a wideband I don't know my real afr. Also I need to know if it is just a rediculus amount of fuel to add so I don't get things too far out of wack. Also my side mount gets very hot even at 8psi and at 17psi it is cooking probably because the turbo is getting so hot from timing retard.

 

[spyderturbo007]

Are you positive that you don't have any leaks? Start by putting your timing back to factory specs. Then take a look at your FP and if necessary, return that to factory specs.

Yes the 2g MAS and the 550cc injectors, should just about cancel each other out. Then you will need to lean out the SAFC a little to compensate for the rich factory maps. So you should end up a little on the negative side.

Also, since you have been running really rich by having your SAFC settings positive, it would be a good idea to replace your plugs, since there is a good chance they are fouled.

Have you verified that your TPS is reading close to 100% (on the logger not the SAFC) at WOT? If so, set your Hi Throttle table to 0% across the board and make another 3rd gear pull, logging airflow, timing, rpm and knock.

 

[92tsifwd]

my tps sits at 8.9% at idle and goes to 99.6% on the logger at wot. My base timing is at 4* btdc and last I checked I had a minor crack or somthing in the ic it self that leaked very litle at 20 psi. Is this why I have to add so much fuel to get rid of this knock?

 

[spyderturbo007]

I would recommend that you take care of your intercooler leak. Even the smallest leak can cause tuning problems.

 

[92tsifwd]

Hey, It has been a little while. I think the knock was because of the intercooler becoming heat soaked so quickly. I noticed that the smic was so hot I could barely touch it. I had no boost leaks and my computer was acting up so this might have contributed to this, I don't know. Either way, I spun a rod bearing and on the way home it died and could not get it started again. If you let it sit over night it will start and then amediatly die so I think the caps are bad. Mabey it was cutting of power to the fuel pump causing the high afc settings. The plugs were all good with one of them having slight oil on it. Looks like it is time to put a 6 bolt in it.

 

[kraka]

Ya...

Just wanna add, you werent hitting fuel cut...You were + on the safc, but the 2g mas compensates for that a little, so in the end the ecu is still seeing less airflow then stock...

You probably had a bad boost leak, which is exactly what it sounds like...Fuel cut would be 1000x worse