1991 mustang 351W swap problems

staabo1

New Member
Jan 3, 2009
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I have a 1991 Mustang LX that has a 1995 Bronco motor that has been Stroked & Bored out to a 396 C.I. It has Forged Probe connecting rods & Pistons, Forged Eagle Crank, Roush Heads, 1.7 Roller Rockers, F303 Camshaft, C&L cai & Mass air, Professional Products Typhoon intake and Throttle Body, 30 LB injectors, BBK adjustable Fuel Pressure regulator and mabe some other things I forgot. Oh and it supposedly has the 95 computer from the Bronco. The Problem is that under hard acceleration it starts to miss or stumble but only under hard acceleration if your driving normal it never dose it. We talked to a friend who teaches a Automotive class but he is more of a chevy guy so he didn't know much of the problem but he said it was most likely a ignition problem, I can't remember the name of it but it has to do with setting the timing but anyway he took that out and said take it for a test drive and while on the drive it seamed to stumble a lot less than when it was pluged in. then he also look up the Fuel Pressure for a 95 Bronco w/351W and said it was supposed to be around 35-45 and the car was set at 30 so we bumped it up to 40 and it still stumbles. Dose anybody has an idea what the problem could be???:shrug:
 
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Your fuel pressure should be around 40psi with vacume pulled from the FPR. Does it still have a tfi style distributor? I would clean the maf sensor as well, especially if there is a k&n filter on it. A dirty mass air sensor will cause weird tip in issues. Whens the last time you did a tune up? Check spark plug gap, and wires. Also would be a TFI module if it does have it. Common problems.
 
Pull the passenger kickpanel and confirm your ecu. Every decision you make from here on out will depend on what ecu you have...

Once you KNOW what ecu you have, check for diagnostic codes. Posts on this board by members 'Joel5.0' or 'jrichker' will get you started on how to pull codes.

What size is the C&L sample tube?
What sensor is on the C&L housing? need part numbers...
What ecu?


jason
 
It has the mustang computer in it. The part number is 099 or (C.A.R.B. EO# D-640)for the c&l air intake. It is a 76 mm mass air. on the back of the tube there is a hole were it looks likes a sensor should be but the guy i bought it from put a bolt in it. does anyone know it there should be a sensor in that hole?
 
what mustang computer? A9L?????? the hole could of been where he had NX at? you do mean on the air inlet tube or the tube inside the MAF? They thing he pulled out? do you mean the PILL? it's located (should be) bt the dizzy in a harness. peace



john:p
 
After i would get my computer flashed does anyone know if i have to the engine timed for the cam. if so does any know what the timing is for a f-303 cam. a 1995 351W is 10 degrees stock. Does stroking and boring it out make the timing different to.
 
After i would get my computer flashed does anyone know if i have to the engine timed for the cam. if so does any know what the timing is for a f-303 cam. a 1995 351W is 10 degrees stock. Does stroking and boring it out make the timing different to.
Yes, the cam should be degreed in, but you are mixing up Ignition Timing with Cam Timing....

You need to pull the ecu and provide the 'Catch Code'
It will be something like...
A9L
A9P
A3M
A3M1
L1C
etc.....

You have me really confused on the description of the MAF.
Can you provide a photo?
Is there a black sensor on top of the MAF housing, with a part number beginning with some thing like...
F1SF
F2VF
etc.....
(it would be held on with 2 small screws)


You are't really providing enough detail on the parts you are working with for us to help you in a meaningful way.

:flag:
jason
 
i went and check the timing and the guy i bought the car from set the timing at 0 so hopefully tomorrow i will set it a 10 degrees and see what that does and give it a tune up and let everyone know what that does.
 
i went and check the timing and the guy i bought the car from set the timing at 0 so hopefully tomorrow i will set it a 10 degrees and see what that does and give it a tune up and let everyone know what that does.
Most likely 'the guy' was talking about CAM Timing. In other words, the cam was not advanced or retarded when installed. It was installed 'Straight Up' or 'Dot to Dot'.

Your ignition timing should be at or around 10-12 degrees.
It's worth checking it...


#099 -
I think this is the 'Calibration Tube' that C&L calls Purple. If that is right, then you MIGHT have found part of your problem.

You MUST ID your ecu.
You MUST ID your MAF sensor.
You MUST remove and measure the inlet and outlet of the C&L sample tube.

For the thing you keep referring to as the screw on the intake tube...
I'm not trying to sound rude, but I can't help with this unless you can get pics. I just don't understand what you might be referring to...