Over the winter I put in Motorcraft spark plugs, and when I got the car out in the spring thats when the problem began, so then I took out the new Motorcrafts and put in splitfire's and the problem continued...

 

Today I talked to a few people and someone gave me the idea that it could be my fuel filter not letting enough gas get to the engine. So, I changed that and my fuel pressure went up 4 pounds. I have ALOT more mid and high end power but still no low end. This made the low end problem even more evident. What I mean is that the car has NO power below about 2,000 RPMs, and it still backfires. Above 2,000 the car honesly has more power than ever before. My question is, what one thing could make the engine lose all power below 2,000 and still have awsome power in the high end? Whatever the problem is, it is somehow only effecting the low end, while the high end is better than ever... Im not sure if that will give anyone any ideas, but thanks for all the help so far anyway!
-Green5pt0

 

Now Im thinking it could be the barometric pressure sensor, a few people mentioned that as a possibility. We'll see.
-Green5pt0

 

the intake you have doesnt have any low end power its ment for high end

 

check your MAF, your TFI and your stater in the distributor, sounds like a TFI module,

 

Check your plug wires, make sure one didnt get fried on the headers or something. I have basically the same mods as you, CAI, 73mm MAF, 70mm TB, Trick Flow Street intake, BBK headers, o/r hpipe, flowmaster exhaust, msd tfi, 9mm wires, autolite #25's, Crane 1.7 roller rockers etc. etc. etc. And the power doesnt hit until about 3000 rpm, that is how our intake works, also the reason I got 4.10's Although I have never had the poping problem.. Which FPR did you get?? I am going to be changing my fuel pump soon as it seems I am not getting the delivery that the engine demands at this point, maybe that's your problem as well..

Check all the easy things like I said, the plug wires, cap & rotor, coil, etc... Then go from there.

 

I know it's not my intake setup that is the problem because I ran the trick flow all last summer and the car ran great. Never backfired or poped at low RPMs once. The FPR i have is BBK. MY spark plug wires are new along with splitfire plugs and a new cap and rotor. I had a 70mm Cobra MAF on the car all along, and I switched back to the stock one just to see what happend, and nothing changed. Also my car never goes lean on my Autometer A/F gauge, so I don't think a lack of fuel is the problem.


What is the TFI? Is is in the distributor? If so how do you check it?

Also, the problem only seems to occur when the engine is hot. I drive up hills under 2,000 RPMs when the engine is cold and it has no problem. When the engine is hot, I lose power quickly while going up hills and then it pops and backfires. This would lead me to think my ignition control module is bad, but I just changed that about two weeks ago hopeing that was the cause of my problem. Does anyone know what else would cause the car to lose power at lower RPM's when the engine is hot?

Any feedback is greatly welcomed!
-Green5pt0

 

first i would say get #25 autolites bc the splitfires suck i had bad experiences with them. Also what is your fuel pressure at? Then i had a poping sound in my intake and it was a vaccum leak from the upper and lower intake gasket so you might want to check that.

 

I was running Motorcrafts when I first got the car out, and it was doing the popping and backfireing. Then I switched to Splitfires and the problem continued. MY fuel pressure is set to 42psi at WOT. And, I had a mechanic at a Ford dealer do a vacume test last week, and it came out perfect. The popping and backfireing seems to be coming from the mufflers and tail pipes. I friend mentioned the Barometric pressure sensor, and said that it adjusts ait/fuel and timing, so that seemed like a possible cause for the problem. So yesterday I went to the junk yard and got one off of a mustang. This didnt solve the problem either. Any suggestions are welcome, is a bad coil possible??
thanks alot,
-Green5pt0

 

I'm going to try to simplify this. Does anyone know what the possible causes could be for an engine losing power, and misfiring once it is warmed up? I have already changed the ignition control module, so I dont think that could be it. This problem deffinitly seems to be related to the engine being hot. Any suggestions are greatly appreciated! Thanks,
-Green5pt0