1995 Cobra killing MAF's?

gandkand3

New Member
Jul 26, 2018
3
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1
Moyock, NC
Hi! I have a stock 95 cobra that I've had since 1998. It's always seemed to have a HP issue, but no-one could ever really pin it down and I didn't have the money to persue it too much so as long as it ran I ok I went with it. It suddenly got to the point where it wouldn't go above 30mph and I took it in to the shop where they said it was a bad MAF and they swapped it out. Suddenly the car was screaming fast(well for a stock 240hp) and I was happy as #$%Q. After about two weeks I noticed a decrease in acceleration/hp and it just got worse to where it was the same as before where the car seemed to run just fine but it wasn't that fast. I brought it back, they swapped MAF's and once again it was fast a %#$^ again. A few weeks later, same issue. I lived with it, but when it started to really have issues again a few months ago I swapped it out for a PRO-M MAF/filter combo and it runs really well........ except after about 5 minutes at idle. Then it starts to surge with the RPM's dropping really low almost to die and then recovering for half a second to repeat and the voltage goes low as well. I've unplugged the MAF and it runs better(steady, no rough idle or surge) without it but of course the CEL is on. I replaced the battery/alternator/coil/fuel filter/cap/rotor and wires with no effect. I am starting to think computer but I hoping someone has had the same issues and can point me in the right direction because everyone I talk to doesn't know what to do. Thoughts? Appreciate any help!
 
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Are you able to work on this car yourself? If so here is a checklist that will pinpoint the problem, yes 94-5 models are a little different from fox cars but the differences are in bold type, start at the top, don't skip around, it will save you time and money.
http://forums.stangnet.com/showthread.php?t=698148

Sorry it's been awhile before getting back with results. Been really busy and it's not my daily driver anymore so I was able to let it sit. So after reading through the checklist, I discovered that I had the big "NO NO" with the cone filter in the engine compartment. I ordered a basic cold air induction that slid the filter to the wheel well and the car has run perfectly the past two days. Thank you! Crazy that something so simple as a filter/MAF placement could fix something that several shops have had no answer to. Thanks again!
 
To kinda explain it think of air flow like water flow, it does not like to change direction, as the air enters the conical filter it's entering the tube from all directions so the air is tumbling around trying to fit, the sensor has a small opening to monitor the air flow and the air does not have a chance to straighten out so it can flow smoothly through the sensor opening. If the conical filter is next to say the fender wall then it will pull more air from the other side thus making the air even more turbulent.
 
To kinda explain it think of air flow like water flow, it does not like to change direction, as the air enters the conical filter it's entering the tube from all directions so the air is tumbling around trying to fit, the sensor has a small opening to monitor the air flow and the air does not have a chance to straighten out so it can flow smoothly through the sensor opening. If the conical filter is next to say the fender wall then it will pull more air from the other side thus making the air even more turbulent.

One more question on this. I had just replaced the MAF sensor and housing a few months ago with a 75MM PRO-M sensor and bullet housing . The CAI kit I put on needs a flanged housing to fit correctly. I called PRO-M to see if they would sell the flanged housing seperatly but they told me with the CAI and the bend to put it in the fenderwell that I would need to recalibrate and I should just buy another MAF with the correct housing for the CAI. I have it rigged to fit with no leaks where it is functional, do you think I need to actualy buy a new sensor that is calibrated for the CAI or jsut look around for a flanged housing so I can connect it correctly? I'm sure it's not "optimized" with this config, but it's functional for a Cobra with no mods. Thanks!