95 GT long cranks/rough

I've held off posting for a while as I did research on the symptoms I am experiencing, so pardon me if I am long-winded (as usual) explaning my problem(s).

A few weeks ago I drove the Mustang to the upholsterer, then to a friend's house; total drive time was about 45 minutes with a good mix of interstate and stop-and-go traffic. The car ran great, which I expected since she has never had any mechanical problems other than the fuel pump a few times and all the seals blowing around 120k miles. My friend and I decided to drive to the paint shop for a quote. About 15 minutes into the drive, the car started running like total s***. She was fighting me, bucking, popping, and sputtering. I'd stick my foot in the gas, and she just wouldn't go. I limped her all the way home (what a painful trip that was since every road I got on had construction).

I couldn't get the codes read immediately, so I went home, parked the car and cleaned the MAF sensor. After cleaning the MAF, she cranked right up and idled fine... perfect problem solved! I bought and installed new Autolite stock replacement plugs (gapped to 0.046") and a cap and rotor since it's been a few years since I paid any attention to the car. After that, I figured she would run great. It was a really long crank and pedal dance to get her started, then she idled like crap and died out a few times. Once I got her to stay lit, she idled fine. I bought a new PIP sensor, but have been reluctant to install as I am not sure I want to tear apart the distributor yet. In the meantime, I finally got my code reader and pulled codes. I got a 564, 172(c), and 176(c) - fan (it's been replaced so I figured it just hadn't been cleared), and both O2 sensors were running lean. Got new O2 sensors and installed them yesterday... same problems exist - long crank, hard to initially get running, then bogs down around 3k RPM if I stick my foot in it. I pulled KOEO codes again and the only code I get is the fan code; got no codes at all for the KOER test.

Now, I am at a loss. I was thinking the PIP sensor (I will probably replace anyway since I bought it), but no codes exist. I thought fuel pump, but once the car is running, it idles like a champ. Maybe a vacuum leak? MAF bad (wouldn't that throw a code too)?

fordtech28 said:

Its most likely the PIP sensor .The symptoms you have described lead to a failing PIP sensor even if no codes exists for the PIP sensor.Its a known issues on our cars

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That's what I figured, but my symptoms didn't sound like the rest of the posts I have read. Looks like I am learning how to take apart a distributor this weekend to see if that fixes the problem.

Installed a new distributor this weekend. No luck. One more step down the rabbit hole though... looks like I have a bad harmonic balancer. I've moved the crank until the TDC mark lines up with the timing needle, crank the car (without it even wanting to light), check the alignment of TDC and rotor, etc... I'm out. So I ordered a new Professional Products harmonic balancer kit last night.

My searches seem to be fruitless... can some one please point me to a how-to on replacing the harmonic balancer?

BANGERSTANGER76 said:

I thought our spark plugs needed to be gapped at .54?????
That may be your problem.

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Possibly... I read that in Haynes too and did a double take as I had read otherwise at numerous other places. It actually ran fine once I could get it cranked. I will pull them out and regap (my arms are sore just thinking about it).

The problem I think I've identified is that the TDC mark on the harmonic balancer was at the 3 o'clock position when the rotor was pointed to the #1 cylinder on the old distributor. I put the TDC mark inline with the timing mark and pointed the rotor to the #1 cylinder on the new distributor and installed. I cranked the car and it turned over like it wanted to light. I checked the TDC mark again inline with the timing needle... the rotor does not point to #1 cylinder (nor is it 180° out). I repeated this three more times.

toyman said:

It's not clear to me what you are doing but it doesn't sound quite correct. You need to ensure that the piston on #1 cylinder it at the top of the compression stroke not the exhaust stroke. The HB will be at "0" at the pointer. The distributor rotor needs to be at about 1 o'clock and pointing to the terminal for #1 cylinder spark plug wire.

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That's exactly what I'm doing. The car would turn over but never light. So I tripled checked myself, and each time the harmonic balancer and rotor were out of sync with each other. This led me to believe the balancer ha spun.

Been a while...

Replaced the harmonic balancer, still won't crank.

I got a fuel pressure test kit today. No pressure, but the test kit was missing the pressure release valve on the gauge. So, still no idea. I got a new fuel pressure regulator and fuel filter and installed them. I let the fuel pump prime a few times... Car still won't crank.

I'm at an absolute loss.

g96v6-250k said:

did this new distrubuter/PIP include a new TFI? it may be remote mounted but its still part of the distributer. if a old ford wont start start with the TFI. even if the timing is off a bit it should still start or atleast pop some. by now you may have fouled the plugs with gas.

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No gas has even reached the plugs yet haha. Still haven't gotten around to replacing the fuel pump.

Update: The problem was a ruptured rubber hose off the fuel pump. Installed new Walbro 255lph fuel pump since I had the gas tank dropped and apart. She runs! Although I think I could stand to hone in the timing a little more as cold starts are a pain (warm starts are no problem at all). I also get a slight surge in cold idle, but once I rev the motor it goes away. She died once when I turned the a/c on though, so that is of concern now. The only things I have not replaced yet are wires, coil, and TFI module. Should I be worried about a very slight idle surge and start looking for more repairs to make, or will timing fix this? I timed as best I could by myself to 13-14° advance. Is this appropriate for a stock motor?

toyman said:

That's an odd statement since timing by one person isn't a problem. You need a timing light and you need to pull the SPOUT jumper before starting the engine. Replace the SPOUT after the timing is set and with the engine running. Since the timing can be set precisely your comment makes me think you are not doing it properly.

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That is entirely possible. I turned the car off, removed the SPOUT connector (the second time I tried this), connected advance timing light to the battery and #1 spark plug wire, restarted the car. I noticed the timing mark seemed to bounce back and forth. I had my wife reve the motor to 2k rpm and the timing mark stopped "bouncing." I then set the advance timing light to 14° and rotated the distributor accordingly (a little more difficult that it should be because I think either I have the wires routed around the EGR/FI mess incorrectly or the wire is too short). I turned the car off and replaced the SPOUT connector, which according to what you said is wrong so I will try again. The long crank, slight gas smell, and idle surge is only on a cold start. Once I've driven it around the block, it will crank immediately.

JonezySN95 said:

Don't rev any to set the timing. If i am correct It won't be an accurate reading. What rpm does it idle at? It should hold a pretty steady 750-800 and you should set it there.

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It idles at 750 just fine (a slight surge as mentioned before). If I time it at idle, the timing mark seems to "bounce" back and forth and makes it hard to set... maybe that is the surge and I should time it when it's warm?

BradleyMustang3 said:

i had the same exact problem. check your tfi(thick film ignition module) its located under your intake tube and check the voltage on your tps. once i replaced my tfi and dialed in my tps to .99 she ran great...tps doesnt have to be .99 between .95 -.99 is good dont go over 1volt

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The TFI module is about the only thing I have not replaced yet. That, coil, and wires. I plan to get the Performance Products version of all three of these, is that a good way to go? Although for aesthetic reasons, I want the MSD coil haha.