Need firing order for an unknown cam

[Rosier]

Hey so. I bought a 95 gt 5.0 ho v8 mustang, and, it’s misfiring hard, and I just figured out it’s probably the firing order due to aftermarket cam.

So does anyone know how about I would figure out the firing order ?

Also would this have hurt my engine ?

 

[07GtS197]

You’ll have to take off the valve covers to check the firing order. If it’s not the ho firing order then it’s the LoPo one, 15426378. Either you’ll find cylinder 3 or 5 as the second cylinder in the firing order. But before you do that, have you tried to rule out other possible issues? Funny enough, even with the wrong firing order it’ll run fine until you step on it.

 

[Randall Garner]

Verify plug wire installed correctly also. #1 tdc verify rotor lines up near #1 if you know cam manufacturer and a part number . You could go to that manufacturer web site to verify which it is. Then you , might be able to narrow down possible remedies to your miss / back firing also wondering why someone would put a non roller cam in place of roller,. In last 10 years looking at cams haven't seen a early 289/302 fire order. Most anyone will change over to the 13726548 order cam.

 

[96blak54]

Was the normal 302 cam timing the same as a 302ho?

If not, you may have a normal 302 engine or a normal 302 cam

 

[Rosier]

So it looks like the firing order is already correct, I’ll have to double check by taking covers off but I think the problem is a vacuum leak from charcoal canister , does anyone know where this line goes, I cannot find it online anywhere

 

[Rosier]

Images *

 

[07GtS197]

The larger line goes to the canister purge valve then to one of the larger ports on the upper intake. Probably the one facing towards the front, if it’s the same as my 87 Grand Marquis. Does the smaller line go to a vacuum reservior? If so that’s for the ac controls most likely. Someone who actually owns an sn should be able to help better. Here’s a diagram that might be useful.

 

[Rosier]

I got both the different Sized lines on the left side of it in the picture hooked up correctly, its the ones I’m pointing at, they connect and then don’t hook up to anything.

 

[07GtS197]

I think you misread what I wrote, there should be an unused vacuum port either on the lower intake manifold or on a vacuum Tee somewhere. It might go to a vacuum tree somewhere towards the passenger side fender according to the diagram I posted. I don’t have a 94-95 gt to look under the hood to help.

 

[RAU03MACH]

if i remember correctly that one is like a vent tube open another term vapor line