scheides
09-14-2005, 01:37 AM
Alright guys, I'm a bit stumped here.
Relivant info/mods:
2g w/ 6-bolt swap, maf-t in blow-through, 650cc FIC injectors, Whiney 255hp, SX FPR
Secondary info, prolly not exactly pertinant:
safc2, fmic, tial bov, ...etc.
Last week, a few days in a row, I was having a studder while at high-rpms while accellerating onto the freeway. After about the third time this happened, I realized I was low (less than 1/4 tank) on gas. I filled up, and the issue went away, straight away.
This weekend, several 20-30 minute drives, still having a bit of an overheating issue w/ my car w/ the ac on in the heavy heat, but other than that, nothing out of the ordinary.
Monday, I drive down to SE metro, and car starts to act funny while at a cruise on the freeway, around 70 mph. I put in the clutch, coast for a second, and it's gone. All of a sudden a moment later, it comes back again. This time, I'm watching all my gauges a bit more closely. Boost/Vacuum and EGT's are normal, but O2 (wideband) is going crazy, from 15.5-19.0:1. Very random.
I pop in the clutch, let the engine fall back to idle for a moment, then resume where I was, and the car drives fine for a bit. I can boost and rev through most of the rev range, but sometimes this condition will hit at high-rpm. Sometimes it will not. But otherwise, at a cruise, almost on queue now, it happens. I pop the clutch, re-engauge, and all is well for a bit.
So, I'm thinking it's something in the intake. Even though I have maf-t, I do a boost leak test from the throttle body elbow back. Voila, hissing from injector #2. I yank it out. Yippee! I've always been fond of FIC injectors until I heard about the shyte gaskets around each end of them. This one has had it. So, I yank all the injectors to swap in the stockers. Several others are not in good shape, so I'm thinking this is part of my problem. So, I reinstall the stockers, still with good condition o-rings, turn down maf-t to zero, turn down s-afc to zero, and turn down my MBC. Car starts and drives fine, then condition comes back.
After car is warm, I yank out the maf and do a boost leak test again. Oops, maybe those o-rings on the stock injectors aren't as good as I thought. I back off pressure on the fuel rail bolts a bit, re-seat the injectors, and then repeat. Seems to hold boost fine now, but guess what. I take the car for a drive, and yup, the issue returns!
MAF/MAF-T seems to read air correctly
Wideband sensor is relatively new, seems to operate correctly
I'm out of ideas for now, anyone else have any? I'll try and post more details as I remember them.
Relivant info/mods:
2g w/ 6-bolt swap, maf-t in blow-through, 650cc FIC injectors, Whiney 255hp, SX FPR
Secondary info, prolly not exactly pertinant:
safc2, fmic, tial bov, ...etc.
Last week, a few days in a row, I was having a studder while at high-rpms while accellerating onto the freeway. After about the third time this happened, I realized I was low (less than 1/4 tank) on gas. I filled up, and the issue went away, straight away.
This weekend, several 20-30 minute drives, still having a bit of an overheating issue w/ my car w/ the ac on in the heavy heat, but other than that, nothing out of the ordinary.
Monday, I drive down to SE metro, and car starts to act funny while at a cruise on the freeway, around 70 mph. I put in the clutch, coast for a second, and it's gone. All of a sudden a moment later, it comes back again. This time, I'm watching all my gauges a bit more closely. Boost/Vacuum and EGT's are normal, but O2 (wideband) is going crazy, from 15.5-19.0:1. Very random.
I pop in the clutch, let the engine fall back to idle for a moment, then resume where I was, and the car drives fine for a bit. I can boost and rev through most of the rev range, but sometimes this condition will hit at high-rpm. Sometimes it will not. But otherwise, at a cruise, almost on queue now, it happens. I pop the clutch, re-engauge, and all is well for a bit.
So, I'm thinking it's something in the intake. Even though I have maf-t, I do a boost leak test from the throttle body elbow back. Voila, hissing from injector #2. I yank it out. Yippee! I've always been fond of FIC injectors until I heard about the shyte gaskets around each end of them. This one has had it. So, I yank all the injectors to swap in the stockers. Several others are not in good shape, so I'm thinking this is part of my problem. So, I reinstall the stockers, still with good condition o-rings, turn down maf-t to zero, turn down s-afc to zero, and turn down my MBC. Car starts and drives fine, then condition comes back.
After car is warm, I yank out the maf and do a boost leak test again. Oops, maybe those o-rings on the stock injectors aren't as good as I thought. I back off pressure on the fuel rail bolts a bit, re-seat the injectors, and then repeat. Seems to hold boost fine now, but guess what. I take the car for a drive, and yup, the issue returns!
MAF/MAF-T seems to read air correctly
Wideband sensor is relatively new, seems to operate correctly
I'm out of ideas for now, anyone else have any? I'll try and post more details as I remember them.