1997 GT In need of help

rdharper02

like kicking myself in the junk
10 Year Member
May 8, 2006
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Just picked up a beautiful red 1997 from a young man who was tired of having it worked on and didnt truly know anything about it . He bought it, killed two pistons on the passenger side, and had the motor replaced with one from a low-mileage 1998. It doesnt run right and is popping the lean faults for both banks. Once i get it to the garage I will replace the fuel filter (car was parked while he deployed for six months), check the vacume (sp?) lines, and then check the fuel pressure. Hopefully that will give me the culprit or remove the problem.

What I really need is to gather info from those of you who are more knowlegeable about the 4.6s than I am. Should i be checking for any other problems from the 98 into 97 swap? Is ther any way to determine if the computer has been tweaked (has some other tasteful mods: baer brakes, diff cover, possibly gears and bbk longtubes) ? Could the "dangling" stock intake (no box) cause this condition? What other areas would cause the lean condition? If you have knowledge please educate me.
 
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Just got a chance to pop the hood today and spent what little time I had dealing with the poor battery connectors ford graced the car with. Hopefully its an easy fix for a draining problem. I did clear the codes and run it a bit, confirming that I do indeed have a lean fault. Did do a quick look over the car and cleaned some of the intake track. I noticed that it has a BBK 70mm TB and a C&L MAF. So I popped the trunk and found more goodies to include a BBK FPR and two extra sets of injectors (another set of orange 19#s and a set of red 30#s). So does anyone know how to find out what flow tube a C&L has? I dont see any numbers on the MAF housing and want to rule out the possibility that the MAF is not calibrated for the 19lb injectors currently installed. Anyone know what symptoms I would get from having a MAF calibrated for 30lbs while running 19lb injectors?

Thanks for the suggestions on previous posts. Trust me, I plan to try them all.

As far as the intake, the only thing holding the MAF/Filter on the car is a stock rubber intake tube. Think I will buy a cheap BBK style to secure it.
 
If the PCM were calibrated for #30's and #19's were installed, Lean would be the result.

It would be a good idea to post the full DTC codes.

An ODB2 scanner with the ability to monitor operational PID's would be a great help if you wish to do this yourself. It may be possible to deduce the base injector size from looking at the pulse width, load factor, air flow, LTFT, and STFT.

The fact that there was an adjustable fuel pressure regulator would indicate the prior owner was attempting to use methods that worked on early 5.0 engines.

I still think the first course of action should be to rule out a vacuum leak.
 
Talked to C&L Performance today and learned that each MAF flow tube is color marked. For the 80mm MAF housing red is used for 30lb and black (or blue) is used for 19lb injectors. Pulled the MAF and I had a red tube, so I confirmed my theory that the previous motor had the bigger injectors in it.

Now I have two options.
1. Buy a used factory MAF housing.
2. Buy the black tube for the C&L piece.

After the replacement I am goiong through my vacum lines. Anyone have a vacum diagram? (Main concern is passing the smog portion of the state inspection.)

Oh, can anyone recommend an inexpensive cold air intake?