Engine stumbles throughout drive range

Nyghtshayd

Nyghtshayd

Registered
Hey folks how is everyone?

I had a slight problem where the CE light would come on but I would get no codes. Also, Nyghtshayd would act as if she were at partial power at WOT then seconds later behave normal.

I changed the CID sensor (top) and the pig-tail, I don't recall what the bottom sensor is called but I only changed the pig-tail.
I recently changed the coil packs (snapped 2 of the screws didn't replace) the symptoms got better for a few days then got worse than before.

The only other thing I can think of is that I over-filled my tank a while ago where i began to smell gas in the car, but that's gone now.

Any clues as to what is going on?

Thank you.
 
Nyghtshayd said:
Hey folks how is everyone?

I had a slight problem where the CE light would come on but I would get no codes. Also, Nyghtshayd would act as if she were at partial power at WOT then seconds later behave normal.

I changed the CID sensor (top) and the pig-tail, I don't recall what the bottom sensor is called but I only changed the pig-tail.
I recently changed the coil packs (snapped 2 of the screws didn't replace) the symptoms got better for a few days then got worse than before.

The only other thing I can think of is that I over-filled my tank a while ago where i began to smell gas in the car, but that's gone now.

Any clues as to what is going on?

Thank you.
Click to expand...

Maybe a tps sensor error, you can check that with a multi meter.

Have you checked fuel pressure under load?

Do you have a chip installed? That could be preventing some of the codes from being read.
 
What exactly are the symptoms? Shaking, shuttering, popping; while driving or in park?
Check and recheck all vacuum hoses for cracks. A micro crack in a hose can give big symptoms. I’ve had old clogged Fuel Filters on older car give a CE light and shutter like it was stalling while driving and gave no code on an OBD1. They are cheap and easy to change if you get the tool. I always recommend changing the fuel filter on a car over 100K miles (low fuel pressure is a killer on a high output car). This could also be an IMRC stuck open.
 
Hi guys,

TPS sensor???
No chip installed.
New fuel pump less than 2 years old.

Engine stumbles throughout driving range (title of thread).
 
What type of "load" does it stumble under? Will it stumble at idle or only when accelerating? Your statement of WOT and then going fine would lead me to believe you are having an ignition problem (plug wires) and you are loosing spark on one of your cylinders and then getting it back again. How long has it been since a wire change?

BTW...its never a good idea to just replace parts in a guessing fashion.
 
Plug wires too can short intermittantly to ground just like the insulators in 2nd gens. Most of us that drive gen 1's have somewhere beyond 100K miles, many of us on original plug wires. Truely, since you were disconnecting and reconnecting the plug wires at the coils, it is even more likely to be plug wires. What other car do you know of that goes 100K miles on a set of plug wires?
 
Nyghtshayd said:
Hi guys,

TPS sensor???
Click to expand...

Throttle position sensor

I had one go bad on my 95. It caused it to do some strange things like erratic shifting and overall crappy running engine.

You might want to open up your hood at night and see if there is any arcing around the plug wires. That could defiantly cause an issue like J said. When was the last time you did plug and wires?
 
The TPS would probably be way down on my diagnosis list with his description, but then again we ARE on the internet and not talking to him in person. I've learned that some people's rattle is a rod knock to me, lol.
 
Nyghtshayd runs smooth and quiet at idle, if I am not paying attention I could leave her running. But when I rev while in park, I hear light stuttering... The plugs are motorcraft about 5 years under 30k mile and the wires around the same. Sadly, I have a set of Autozone lifetime wires. Where is the TPS located?
 
Typical plug wire failure. No miss at idle or revving up with NO load, runs rough under the load of the car.

Change your wires, do NOT do your TPS.
 
Yah I agree sounds to be a spark issue if it idles ok but drives bad. I would start by replacing all the plugs regardless how they look. They can crack and you can’t see it
 
If you don’t already have one I suggest you go to your auto part Store and get the Ford/Lincoln/mercury OBD1 code reader Scan tool its only $29.00. I use it on my 94. It will do a diagnostic, not as good as the OBDII but a big help. And it can be used to make the air ride do a diagnostics to. Cool to watch.
 
ggfrank21 said:
If you don’t already have one I suggest you go to your auto part Store and get the Ford/Lincoln/mercury OBD1 code reader Scan tool its only $29.00. I use it on my 94. It will do a diagnostic, not as good as the OBDII but a big help. And it can be used to make the air ride do a diagnostics to. Cool to watch.
Click to expand...

FCOL: now the battery light is on?!?!?

Everywhere I went didn't have that scanner so I use the self test input grounding and count away. BTW, the codes I got was 636 AC not connected and 586 transmission temp, nothing that would cause the problems.

Thank you all, I am gonna go change the wires and check the plugs.

I'll tell you all how it turns out.
 
95blklsc said:
Yea at 5 years old I would start with plugs and wires too.
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oops, I just found the receipt, it's 2yo and nyghtshayd has been sitting for that long since she was hit.

The coils inside the MAF sensor look fuzz. Could that cause these problems?
 
I q-tipped the resistors inside the MAF sensor, then KOEO the codes:

157 - MAF sensor went below 0.4 volts during the last 80 warm-up cycles. (ran Nyghtshayd a few times w/o it attached)
543 - When the PCM commanded the fuel pump on, voltage was not detected on FPM. (fuel pump has less than 2 years usage on it)
586 - AC not connected.(disconnected B/C of rotted AC line)

Still runs smooth at idle, slight stutter reving in park, stumbles while driving. I am looking for an inexpensive fuel pressure gauge.
Also, the battery light comes on intermittently in park and while driving....@#$%
 
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You might be able to rent a fuel pressur gauge from auto zone. You may need to buy a right angle fitting and extsion so you can run it out and tape it to the windshield. You want to do this so you can take a look at the pressure under load.
 
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Thanks, I'll do that. I hope it is not the fuel pump, I hear it clearly when I turn Nyghtshayd on...If so, at least i don't have 9 gallons in the tank like last time.
 
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Any resolution?

Any resolution?

ggfrank21 said:
Yah I agree sounds to be a spark issue if it idles ok but drives bad. I would start by replacing all the plugs regardless how they look. They can crack and you can’t see it
Click to expand...
Any resolution? I have a similar problem.
 
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