my 99gsx sputtering fixed but another concern

[dale187]

Hey guys that real bad sputtering and bogging i had is for now under sontrol. We by passed the MBC and hooked up the stock boost control, and it is boosting 10psi on the stock 16g. Changed oil spark plugs and wires. Stayed next for a 14.6s bmw 330ci, is that decent?? The only concern i have is that i could only get it runing decent with the fuel pressure at 20. For some reason when i tried the bfp at 43.5 it acted like it wanted to shut off. Could this be a faulty afpr? I don't understand it. Car is going in the shop tuesday to have a cat put on it so i can get through inspection, then tinker with more stuff. I havent done a boost leak test yet which i do plan on it right here in the near future. But yea if anyone could give me any suggestions on the fuel pressure and anything else i stated in this thread it would be greatly appreciated. Thanks so much guys

 

[dale187]

anyone?

 

[DRAGIN]

Wow that's a really complex question. Clearly 20psi fuel pressure is very bad. It sounds like you have a fuel pressure problem. Bring the base fuel pressure up to 38psi or so at idle and recheck it. It's simply fuel and air mixing and spark igniting. If it's running super fat at 38-40psi then you likely are not getting proper air flow into the engine or air metering (MAF) is screwed up. Check for proper MAF output voltages (refer to manual or DSM Manual on CD) and check for smaller boost leaks. If you had a massive leak it'd fall on it's face under boost. Also run a compression test and scan for codes. Get back to us after you've done all that.

 

[dale187]

Your saying try and set my fuel pressure to 38 while the car is idling ?

 

[pj91gsx]

43 is correct for 2g if Im not mistaken. Auto may vary with fuel pressure too. what kind of fpr do you have? The ebay ones are no good.

 

[dale187]

Its a aeromotive something can never remember the name of it.. It's not an ebay one. Like i said it's set at around 20 psi.. Doesn't sound right? yea i know.. I dont understand it either.. But it's running fantastic compared to the way it was.. And i ran a 330ci from a roll, he runs a 14.6 and i was side by side with him at 10psi. Had we gone from a dig, i would have beaten that 14.6 time you know? I'm lost, base fpr is supposed to be at 43.5

 

[pj91gsx]

the way you set the fuel pressure, is let the motor idle and disconnect the wastegate line, then set the pressure and connect the line and the fuel pressure will go down to adjust.

 

[knochgoon24]

... it is boosting 10psi on the stock 16g...

If your car is stock, it has a T25.

 

[8urv8]

He bought this car a few month's ago from a dealer so we don't know what is all done to the car beside's the obvious evoIII 16g. I'm thinking the car has got bigger injector's and that's why the car is running bad when he turns the fuel pressure up to where it should be. Does this make sense? I really haven't had a chance to look his car over since he got it but I've talked to Dale on the phone a few time's trying to give him some idea's about some of his isssues. I recommended he check his injector's to see what he's got and get I wideband so he can see where his Air/Fuel ratio is. Also, some sort of air/fuel controller would be good idea as well. Dale if you take some picture's of the car and post them up here you may be able to find the original owner or someone who may know who the car belonged to.

 

[pj91gsx]

bigger injectors will cause the car to run crappy without a compensation.

 

[mentalTSiAWD]

He bought this car a few month's ago from a dealer so we don't know what is all done to the car beside's the obvious evoIII 16g. I'm thinking the car has got bigger injector's and that's why the car is running bad when he turns the fuel pressure up to where it should be. Does this make sense? I really haven't had a chance to look his car over since he got it but I've talked to Dale on the phone a few time's trying to give him some idea's about some of his isssues. I recommended he check his injector's to see what he's got and get I wideband so he can see where his Air/Fuel ratio is. Also, some sort of air/fuel controller would be good idea as well. Dale if you take some picture's of the car and post them up here you may be able to find the original owner or someone who may know who the car belonged to.

Yes, that will cause the problem you guys are discussing. evoIII 16g big injectors and no afc will make it run fat, you need something to turn down the fuel (safc, neo, dsmlink) and need to properly set the fpr. That should help out a lot if you do indeed have a 16g and big injectors.

 

[dale187]

You guys have been a great help. Any idea where i can get a used wideband off anyone? If so could you give me links? I wanna get the car on the road as soon as possible but more importantly i want the car to run reliably. I'll be taking and posting pics off the car and maybe from pics of the motor you guys can give me some more ideas. Thanks guys