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Good day to everyone. I am having a hard starting condition with my 1997 Ford Thunderbird LX 4.6l V8 AED Supercharged (6 psi kit). I purchased the vehicle used with the kit already installed. The vehicle has (I believe) a shift kit as it has a hard shift from first to second gear. There is a custom exhaust (nothing great, but slightly better 'sounding' at least than stock). There are NO other modifications that I am aware of (other than the parts that came with the AED kit). When turning the key, I do hear the fuel pump turning on. I have Accel wires on the vehicle, and have purchased the Lightning Spark Plugs (should be gapped at 0.40" anyone have advice on this?)

The problem is as follows: Check Engine Light is always on (except after I have the car up over the winter in storage, and battery removed; at which point after reinstalling the battery, it will take a couple of days; sometimes hours only to come back on). The car takes many attempts to start; initially it 'trys' to do so, and idles very roughly at first and will go away after about 30 seconds or with light pressure on the throttle. The car failed emissions here in CT, but I was able to get it to pass by the battery removal procedure above. The OBD II codes listed by the emissions tech. were : P0171: System too Lean (Bank 1)(2). I brought the car to the dealer; they told me that they suspected that I had a leak by the intake manifold, but that they wouldn't touch it due to how tightly everything is in the engine compartment/how complicated and labor intensive it would be (i.e. they didn't want to even try as they knew they would screw up). Prior to this occasion, the dealer replaced the idle air control valve to try and rectify the hard starting issue and check engine light (not sure if they are related or separate problems). The person from whom I purchased the car solved the check engine light problem by placing a piece of black electrical tape over the instrument panel above the light (great fix, huh?) He stated to me that he was told it was the "fuel system oxygen sensor" that was bad, but never cared to have it replaced, as the car ran "like a bat out of hell." Now don't get me wrong, it does feel like the car has more power over my previous stock Thunderbird, but it does NOT feel significant enough to make me believe that the supercharger is working to it's optimum efficiency.

I have since brought the vehicle to a private mechanic that has a lift garage on his residential property and has worked on supercharged applications (Mustangs/Fords only). In speaking with him and Scott at AED, we put a fuel pressure gauge on the vehicle; should have been running at 70 psi; only getting 60 psi. Replacing the fuel pump got the pressure back to 70 psi, but hard starting issue still remains. Replaced the STOCK fuel pressure regulator next (not the supplemental one that comes with the AED kit). This still has not solved/rectified the situation. The following has been suggested to me, but not sure where to go; I don't want to just throw parts at the car and hope that it resolves the issues.

Issues suggested as being possible culprits:

Crank sensor needs replacing
see link:

Faulty fuel vapor valve (not even sure what this is...)

MAF sensor bad (wouldn't there be an OBD II code/check engine light code specific response from the computer)

I'd like to upgrade the vehicle to the AED 9 psi kit and get rid of the FMU; and go with the 30 lb injectors....all working towards my goal of first getting the car up to "where it should be," and then a goal of 300 RWHP (don't want to modify this until it is operating normally, obviously). If anyone has suggestions on this as well as to how I might most cost effectively go about this, I would LOVE to hear from all of you; you've all given me great advice in the past, and am hoping you will be able to do so once again :)

Thank you everyone in advance, please email me at [email protected] or post in this forum; I would be more than happy as well to speak with anyone on the phone as well.

James L. Smith
Wethersfield, CT
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