Help!!! Timing issues maybe?

[Juggalo95]

OK heres the deal my 95 GT Aode car has a problem that when I have 87octane it wants to misfire..car jerks in the 1500~1700rpm range..if I give it more than half throttle it downshifts and its fine...I put a new cap and rotor on and filled up with 92octane and its a lot better and only does the misfire thing in the same rpms but only on inclines it seems. Is my timing off? bad plugs and wires? Coil? I havent did anything to the car since Ive owned it and although the car is in good shape for its age I doubt the previous did a tune up since the plg wires say 1995 on it. Could I possible have a vacuum leak? I noticed the vacum line that goes from the intake manifold to the passenger side inner wheel well looks a lil dry rotted. Please help anysuggestions appriciated

 

[PUNISHER RACING]

I would start with a tune up (plugs,wires,cap,rotor,can of Seafoam) and go from there.

 

[go-stang5.0]

Yea if that stuff looks old...assume its really old and time for replacement. I would also replace the fuel filter while your at it. As mentioned before...go from there. That might cure your problem...but if not..at least you'll get better gas milage and power.

 

[PUNISHER RACING]

+1 on the fuel filter too Thanks, I forgot that

 

[BlownFiveLiter]

Any idea what your base timing is set to (spout unplugged)?

 

[HISSIN50]

Another vote for the spark leak. You could mist the wires with water at night and see if you note bleeding (be very careful of moving parts in the dark).

Or sheathe the wires and see if the issue gets better.

The Low RPM and/or an incline exacerbate the issue.

The last thing I'd do (though I dont think it's an issue) is to check your TPS in case the wiper has a dead spot at 1.5-1.7K RPM.

Good luck.

 

[95BlackTan50]

On the spark leak, look under the coil as well. When I was troubleshooting my PIP problem I went from my Blaster coil to the stock coil. It started pinging badly so I checked for spark leaks in the dark. I was amazed just how much the coil was arcing to ground. I put the Blaster coil back on and that problem went away.

Ditto on the fuel filter. Also check fuel pressure. It's easy enough to do with a gauge. It should be around 32 PSI with the vacuum hose disconnected from the regulator.

Checking the engine fault codes is pretty easy too. Instructions are in any shop manual and somewhere on this forum. All it takes is a paperclip to start the test and count CEL flashes from the drivers seat. A failed test code might point you in the right direction.

All of the recommendations I've seen so far are cheap and pretty easy to do.

 

[HISSIN50]

Also check fuel pressure. It's easy enough to do with a gauge. It should be around 32 PSI with the vacuum hose disconnected from the regulator.

I think you mistyped. 32 PSIG would be appropriate with the vac line connected. Look for about 38-39 PSI with the vac line disconnected.

 

[Juggalo95]

Ok I dont bet any engine codes with the decoder deal. Im gonna try the fuel filter and check my timing.

Im a noob to fords as Ive only owned sbc chevys and b series hondas...so how do I do the timing on a 5.0? Whats the "spout" I keep hearin about?

Thanks for all the help thus far

 

[HISSIN50]

Timing article

 

[95BlackTan50]

I think you mistyped. 32 PSIG would be appropriate with the vac line connected. Look for about 38-39 PSI with the vac line disconnected.

Sorry, senior moment. Thanks for catching that.