Guys,
Looking for ideas. For background, my CObra has about 22K miles on it, mostly on the road course. After a bunch of medical issues, the Cobra is lucky to get 50 miles on it for the past 7 years or so. Up till 6 weeks ago, car was running fine.
Installed a dual bank A/F gauge. Noticed both banks register lean (21-22) until car warms up, then drops to 15-16. SInce I had a Pro-M 75 bullet w/ CObra calibration on it, I figure that's normal. Reason why I installed the gauge is because I bought a K-B blower when they stopped making the 5.0 version, and I was going to have my old buddy Chris Winter install it (I know, but I don't have the time). Anyway, I decided to do some of the work up front and swapped my Texas Turbo (!) underdrive crank pulley for a stock GT and removed my strut tower brace. Now the car is hard as hell to start.
So, I decide to put the stock MAF back on the car, after disconnecting the battery for a week. Car is still hard as hell to start, but after starting lean, car drops to 14.5/15.5 once warm. Way back when, I put a K-B adjustable fuel pressure regulator on the car (1995?). So, I decide to screw it in a 1/2 turn and see what happens. Fuel pressure increases from about 30-31 at idle to 32 (Autometer electric FP gauge, installed in the fuel rail). Wait a touch, restart, car is still hard to start but sounds better. So, I decide to turn it another 1/2. Car sounds a bit rougher, fuel pressure dropped to just about 20 PSI! If I step on the pedal, the car sounds powerless and the A/F gauge shows real lean. I shut it down, and walk away before I make shit worse. But I did look at the regulator again, and when I go to make sure the vacuum line is on completely (it looked "off"), I see the fitting pulled out of the regulator. I used some hi-temp sealer to reglue the fitting and walk away, this time for good.
I have a feeling the regulator is shot, so I ordered a replacement. I also have a set of rebuilt and flow matched injectors I bought several years back that I'll install. And, to be complete, I'm going to change the O2 sensors and fuel filter.
Now, for the opinions. Does it sound right for the Cobra to start that lean, then come into "normal" range once it warms (wish I installed that gauge years ago)? If I remember, a stock CObra is around 32 PSI of fuel pressure on the rail at idle, is my memory correct? And why does everyone think the car became so hard to start once I swapped on the GT crank pulley? And, finally, does anyone have any ideas for me? I figure once I do the parts swap, I'll also turn the timing down to stock, hoping that will allow the car to turn over easier.
Looking for ideas. For background, my CObra has about 22K miles on it, mostly on the road course. After a bunch of medical issues, the Cobra is lucky to get 50 miles on it for the past 7 years or so. Up till 6 weeks ago, car was running fine.
Installed a dual bank A/F gauge. Noticed both banks register lean (21-22) until car warms up, then drops to 15-16. SInce I had a Pro-M 75 bullet w/ CObra calibration on it, I figure that's normal. Reason why I installed the gauge is because I bought a K-B blower when they stopped making the 5.0 version, and I was going to have my old buddy Chris Winter install it (I know, but I don't have the time). Anyway, I decided to do some of the work up front and swapped my Texas Turbo (!) underdrive crank pulley for a stock GT and removed my strut tower brace. Now the car is hard as hell to start.
So, I decide to put the stock MAF back on the car, after disconnecting the battery for a week. Car is still hard as hell to start, but after starting lean, car drops to 14.5/15.5 once warm. Way back when, I put a K-B adjustable fuel pressure regulator on the car (1995?). So, I decide to screw it in a 1/2 turn and see what happens. Fuel pressure increases from about 30-31 at idle to 32 (Autometer electric FP gauge, installed in the fuel rail). Wait a touch, restart, car is still hard to start but sounds better. So, I decide to turn it another 1/2. Car sounds a bit rougher, fuel pressure dropped to just about 20 PSI! If I step on the pedal, the car sounds powerless and the A/F gauge shows real lean. I shut it down, and walk away before I make shit worse. But I did look at the regulator again, and when I go to make sure the vacuum line is on completely (it looked "off"), I see the fitting pulled out of the regulator. I used some hi-temp sealer to reglue the fitting and walk away, this time for good.
I have a feeling the regulator is shot, so I ordered a replacement. I also have a set of rebuilt and flow matched injectors I bought several years back that I'll install. And, to be complete, I'm going to change the O2 sensors and fuel filter.
Now, for the opinions. Does it sound right for the Cobra to start that lean, then come into "normal" range once it warms (wish I installed that gauge years ago)? If I remember, a stock CObra is around 32 PSI of fuel pressure on the rail at idle, is my memory correct? And why does everyone think the car became so hard to start once I swapped on the GT crank pulley? And, finally, does anyone have any ideas for me? I figure once I do the parts swap, I'll also turn the timing down to stock, hoping that will allow the car to turn over easier.