I'm 99% sure that just means the computer hasn't relearned its fuel tables yet, something like 10-30 minutes of driving. Somebody please chime in if you know for sure.
01 Cobra w/Vortech...help/suggestions
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I'm 99% sure that just means the computer hasn't relearned its fuel tables yet, something like 10-30 minutes of driving. Somebody please chime in if you know for sure.
So Bob Kurgan and Randy Stitchcomb are wrong? :shrug:
The OBD computer has a drive cycle in which it tests all of its monitors (fuel tank vent, 02 sensors, egr, etc. It is not as simple as 10 to 30 minutes of driving.
the instructions are as follows:
http://www.obdii.com/drivecycleford.html
Well I'm not getting the P1000 code anymore or anyother code for that matter. I took it to my mechanic yesterday and I went for a drive with him and let him drive it. It died twice and bucked like crazy in the 2000-4000rpm range while cruising the car. Could it be a timing issue? If so, how do you adjust the timing?
brkntrxn: My MAF is routed through the fender as shown:
brkntrxn: My MAF is routed through the fender as shown:
Also, would a faulty Bypass Valve cause my problem? Could the supercharger develop a surge from a faulty bypass valve and that's causing my engine to die when the clutch is pushed in and then causing the crazy lean out readings and bucking at cruise?
Would a fuel pressure and boost gages help determine what the problem is? This way he could rule out the fuel system and understand what the sc is doing?
Okay, I just got my problem with bucking around 2000 rpms fixed. Of course, all solutions for all cars will be different, but I got it identified.
I tried baffling the air from the bypass valve, which didn't work. I logged MAF counts before and after, didn't look any different.
I was going to install a wind shield around it, but I asked my dynotuner yesterday and he said that if I had installed the baffle to account for MAF backwash, he was certain it was the EGR. When he tuned the car, he adjusted the EGR, and the car cruises nice and smooth at all RPMs.
I tried baffling the air from the bypass valve, which didn't work. I logged MAF counts before and after, didn't look any different.
I was going to install a wind shield around it, but I asked my dynotuner yesterday and he said that if I had installed the baffle to account for MAF backwash, he was certain it was the EGR. When he tuned the car, he adjusted the EGR, and the car cruises nice and smooth at all RPMs.
Vacuum leak?
My car had experienced similar symptoms. It turned out to be a vacuum (intake gasket) leak.
At light loads and speeds above 40 mph it would misfire badly and after the engine was hot it would do it consistently. It drove me nuts.
I replaced the DFPE sensor and checked lines, cleaned EGR valve, New plugs, checked vacuum lines/fittings again, cleaned MAF, cleaned idle air control valve, new injector o-rings, you name it. No effect.
What threw me was that it acted like something electrical driving it as the misfiring would turn on and off suddenly depending on conditions.
It appears that the (slight) vacuum leak was causing a lean condition (at light loads/high vacuum conditions) and would begin misfiring only when the EGR opened up.
Upon removal of the lower intake, I noticed the lower intake manifold had some rough machining from the factory near the the #1 and #2 intake port and evidence of boost leaking out in that area.
My car had experienced similar symptoms. It turned out to be a vacuum (intake gasket) leak.
At light loads and speeds above 40 mph it would misfire badly and after the engine was hot it would do it consistently. It drove me nuts.
I replaced the DFPE sensor and checked lines, cleaned EGR valve, New plugs, checked vacuum lines/fittings again, cleaned MAF, cleaned idle air control valve, new injector o-rings, you name it. No effect.
What threw me was that it acted like something electrical driving it as the misfiring would turn on and off suddenly depending on conditions.
It appears that the (slight) vacuum leak was causing a lean condition (at light loads/high vacuum conditions) and would begin misfiring only when the EGR opened up.
Upon removal of the lower intake, I noticed the lower intake manifold had some rough machining from the factory near the the #1 and #2 intake port and evidence of boost leaking out in that area.
I would have to say after all the things you replaced I'm sticking with it being the bypass valve.
If no one else answered, timing is normally adjusted via a tune.
It appears that your MAF is a draw-thru setup. You can still try clocking it as I suggested and see if it helps.
Think we've found the problem. I found 4 manifold bolts loose and 2 that had about 1/8inch thread left from tighten down. I'm saying my manifold gasket is defenitely blown. Ordered a new one and will try to get it on Monday and hopefully that will cure my problems.
Thanks for everyone's input...especially about the intake gasket possibly being blown because I didn't even think to check all that stuff. I was checking vac lines and electrical parts instead of bolts and gaskets. Thanks again and I'll let you guys know if the new gasket cures my problem.
Brad
Thanks for everyone's input...especially about the intake gasket possibly being blown because I didn't even think to check all that stuff. I was checking vac lines and electrical parts instead of bolts and gaskets. Thanks again and I'll let you guys know if the new gasket cures my problem.
Brad
if you bvp is messed up it will hang closed not lettin the recycled air to come back in front of the supercharger causing it to starve i have the same kit on my 99 cobra well i did still trying to sell it but pull the vacume line off and suck on it to see if you can hear or feel the boot moving in side that will tell you if its not working could be what your problem is.
Cool, let us know if that is the fix so it can be available for future searches.
The intake gaskets (upper and lower) were not blown but we replaced them anyway...problem still NOT fixed. The only thing I know to do now is to buy a new MAF. So where can I buy a new MAF sensor for 42lb. injectors? I really would just like to buy the sensor and not the whole pipe and kit or whatever. The one I had is the one that came from Vortech for 42lb. injectors...I believe it's a C&L type but not positive. What's your suggestions? Thanks.
Oh yeah, this weekend I gotta P0171 and P0174 codes...but that doesn't help me much about pinpointing my problem since that could be due to a blown intake gasket (mine's fine) or bad MAF.
Oh yeah, this weekend I gotta P0171 and P0174 codes...but that doesn't help me much about pinpointing my problem since that could be due to a blown intake gasket (mine's fine) or bad MAF.
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My apologies, but what exactly do you mean by "clocking it"?
Rotate.
Rotate the MAF within it associated tubes in small increments (cw and ccw) to see if it affects your idle quality. MAFs are sensitive to their placement within the air stream. If the air hitting the sensor is in a turbulent spot, it can affect idle quality.
If he is using a Vortech bracket he will not be able to rotate it.
I had thise problem right after my eaton swap then i went with the 03 cobra pumps and tank it stopped. check your fuel presure, and if you can do a fuel volume test. see if its just resistance. Do you have another maf to plug in?
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