I have a 2001 4.6 DOHC Cobra. Stage 3 cams, lots of engine mods, 90mm SCT MAF, 39lb injectors CAI, accufab TB, BBK headers and more. I have had 2 tuners try to help. 400 RWP on dyno. He is my problem. It stalls all the time. When it idles it's fine but will randomly stall like someone turned off the key. It will start back up no problem. Sometimes coming to a stop it will stall. I have smoked for vacuum leaks, changed all epa devices and even removed the EGR system .Also changed out the pcm too. Random misfire code sometimes but I was told due to cams. One tuner jacked up the idle so high it's undriveable. Only 300 miles on the new motor. Any ideas what to look for or do?? I am giving up
2001 SVT Cobra stalling issues.. Help
- Thread starter daddiod
- Start date
So if it's in your driveway idling it'll be fine? Or will it just decide to stall? Does it stall every time you slow down to come to a stop?
Did you adjust the throttle body stop? Accufabs tend to need some adjustment at first. For the stalling when slowing down the dashpot decay needs to be adjusted.
Did you adjust the throttle body stop? Accufabs tend to need some adjustment at first. For the stalling when slowing down the dashpot decay needs to be adjusted.
Sometimes just in driveway will stall-shut off. Is not everytime I stop either just most of the time. I didnt try adj the throttle stop due to accufab telling me to leave it alone. I can check on the dash pot decay. Its been over a year on and off with this great car.
if you change the MAF size (from 80mm stock) then the ECU needs to be adjusted to the new 90mm MAF you want to run. same with changing your injectors from 24LB to 39LB. i did try to install a aftermarket MAF on my 03 cobra, the car started and idle for couple mins, then while driving it ran pretty bad and then would just stall out. the car did not run with the stock tune and bigger MAF.
i had the car dyno tuned and my stock ecu was adjusted to my aftermarket MAF and my car ran better. i had a weak alternator issue causing some fuel pressure drop.
i suggest try to install a stock 01 cobra 80mm MAF and Stock 24 LB injectors and run it on a stock 01 cobra computer and see if the stalling is fixed .keep on the CAI, ACCUFAB, HEADERS, EGR DELETE, EVAP DELETE AND CAMS. if so then the stalling is related to the 90mm MAF readings not being read correctly by the computer becuase it thinks you have a 80mm MAF still and it will shut the engine off while trying to drive it to prevent damage to your engine (lean condition from improper MAF signal)
i had the car dyno tuned and my stock ecu was adjusted to my aftermarket MAF and my car ran better. i had a weak alternator issue causing some fuel pressure drop.
i suggest try to install a stock 01 cobra 80mm MAF and Stock 24 LB injectors and run it on a stock 01 cobra computer and see if the stalling is fixed .keep on the CAI, ACCUFAB, HEADERS, EGR DELETE, EVAP DELETE AND CAMS. if so then the stalling is related to the 90mm MAF readings not being read correctly by the computer becuase it thinks you have a 80mm MAF still and it will shut the engine off while trying to drive it to prevent damage to your engine (lean condition from improper MAF signal)
Weird. I had a long post here that apparently disappeared.
Don't swap the MAF or injectors. Running stock stuff with your current tune and cams will cause more issues and you won't know what's causing it.
Adjust the throttle body and go from there. Even if it was adjusted correctly from Accufab (which I doubt it is) running aftermarket cams changes everything. You'd be amazed how something so simple can make a big difference.
Don't swap the MAF or injectors. Running stock stuff with your current tune and cams will cause more issues and you won't know what's causing it.
Adjust the throttle body and go from there. Even if it was adjusted correctly from Accufab (which I doubt it is) running aftermarket cams changes everything. You'd be amazed how something so simple can make a big difference.
I am going to try adjusting the throttle body. I talked to acufab and told me to leave it alone but....I have has a few tell me to manually adjust it with the IAC disconnected first the plug in. I will post after I try this. Thanks
If you know how to datalog set up a log to watch IAC duty cycle. Open the blade slowly until the duty cycle hits about 30%. That's what I aim for and it seems to work fine. The RPM will raise for a couple seconds then settle back down. Once the stop is adjusted check your TPS.
ok i do agree the car should run good and not stall with the aftermarket MAF and Bigger Injectors if it is tuned for those parts. the car put down 400hp to the tires. it has a stalling issue and a check engine light for misfire. i think it should be able to run good and idle decent and not stall and only have a check engine light for missing cats or missing egr sensor.
the stalling issue can be due to the Aftermarket Maf and to try to fix the stalling i suggested run the stock Maf, stock injectors and Stock tune and drive it to see if it doesnt stall out. even with the accufab set the way it came from the factory. it should be pretty easy to change the maf to stock and use the SCT to return the Ecu to stock. it is a little harder to change all 8 fuel injectors back to stock i do admit!!!!
the problem could be with the accufab throttle blade adjustment too , i would try to leave the setting screw the way it was from factory.
i would DEF recommend a compression check and a leak-down test if possible. if it passes the 2 engine mechanical checks then it could be a weak coil pack or 2 weak coil packs.
the stalling issue can be due to the Aftermarket Maf and to try to fix the stalling i suggested run the stock Maf, stock injectors and Stock tune and drive it to see if it doesnt stall out. even with the accufab set the way it came from the factory. it should be pretty easy to change the maf to stock and use the SCT to return the Ecu to stock. it is a little harder to change all 8 fuel injectors back to stock i do admit!!!!
the problem could be with the accufab throttle blade adjustment too , i would try to leave the setting screw the way it was from factory.
i would DEF recommend a compression check and a leak-down test if possible. if it passes the 2 engine mechanical checks then it could be a weak coil pack or 2 weak coil packs.
yeah unfortunately the cams might have messed up a valve and the problem could be due to a leaking valve, intake or exhaust, causing compression loss. i would warm the car up for 15 mins and take the spark plugs out and check the compression in each cylinder, record the results for comparison. i am thinking the pistons and bottom end on the engine are good.
the computer is throwing the misfire codes because it sees the RPM signal and can tell when a cylinder is too weak compared to the rest. sometimes it can tell cylinder 1-8 if you drive it for long enough.
the computer is throwing the misfire codes because it sees the RPM signal and can tell when a cylinder is too weak compared to the rest. sometimes it can tell cylinder 1-8 if you drive it for long enough.
Except for the stalling it runs awesome its like the key is shut off. No indication whats going on and will start right back up.. I only have about 300 miles on this engine and was built by Modular head shop in Fl. But I will do this too I need to figure this out. Thank you. Will post what I find out.
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