Car is sort of sputtering...?

g36 monkey · Apr 15, 2013

Well, I think I already know, but I want to see what you guys think.

Mind you, aside from the motor and trans and suspension and brakes, this old clunker has 210k on the clock.

Basically, what's happening is after I drive the car any real distance, and it varies, could be 20 miles, could be fine up to about 60, but even if I'm just cruising, once I slow down to a stop, then go to accelerate, the rpms won't climb. It will be strong in the bottom end, but as soon as I hit say 4,000 rpms, it refuses to go any higher. Temperature is fine, oil is fine.

My guess is the fuel pump is on its way out, and after heating up its upset. Because upon first firing up, it runs pretty strong, though I can still feel a little less power than normal around 4.5k

I went ahead and ordered the SVT focus pump since I had planned to do that anyways before I finish up the 8.8, but does anyone have any other suggestions?

Orange 94 · Apr 15, 2013

Weird, like it won't go above around 4k? I was having difficulty with my top end too, mine was sputtering little higher up though. New valve springs and coil seemed to help if i remember correctly?

g36 monkey · Apr 15, 2013

Coil is pretty much new. I'll see if the pump fixes it. But it does seem like a fuel delivery issue. And just checking pressure wouldn't help because it's only at high rpms under load, because I can still rev freely (to my knowledge at least, I've done it a few times and it worked fine)

Orange 94 · Apr 15, 2013

Yeah the fuel pump could be a likely cause.

TanTop94 · Apr 15, 2013

Might want to change your fuel filter while your at it.

g36 monkey · Apr 15, 2013

fuel filter is still relatively new, but it won't hurt. it did this once a long time ago, when I autocrossed the car. Like I said, if I let it cool all the way down, it's like nothing ever happened, but lately it's happened much more frequently, even on the drive home and drive to work I am noticing it =/

TanTop94 · Apr 15, 2013

Is your pump whining any? I know mine was screaming when it started to go bad. Dont forget to get a new filler neck grommet as well!

Twista · Apr 16, 2013

i think mine did this with bag plug wires (burnt) and maybe bad plugs. Changed both @ same time

g36 monkey · Apr 16, 2013

It's not making any excess noise.

Today:

It was doing the limiting thing again on my way home from work. Stopped, got some gas, left and was able to drive it fairly hard the whole way home (1.6 miles)

Dunno?

I think it might be getting too hot with less fuel in the tank? (it was at 1/4 when I filled up)

Orange 94 · Apr 16, 2013

Could it just be a bad tank of gas?

g36 monkey · Apr 16, 2013

No because it has done it now for a few tanks lol.

Orange 94 · Apr 16, 2013

ah gotcha! I tried lol

RichV · Apr 16, 2013

Sounds like something electrical related. Do those have crank sensors? COP? Sorry just not familiar with the engine control.

I had a 5.0 that jumped time once due to a loose timing chain, and it did almost exactly what you're describing. Only difference is it as pretty consistant, not intermittent.

g36 monkey · Apr 16, 2013

It does have a crank sensor, the damn thing goes bad once a month. This is the 5th one I've had in the car now. When I order the filler neck grommet thing I'll be ordering a motorcraft sensor for it instead of a parts store replacement.

I don't think the timing would have jumped though, I hope not at least. It's all pretty new, 18k miles

RichV · Apr 16, 2013

Prolly not. I just saw 200K+.

95opal · Apr 16, 2013

Tew is that the only systom? Is it having issues with hard starting at all or just what you described.

g36 monkey · Apr 16, 2013

95opal said:
Tew is that the only systom? Is it having issues with hard starting at all or just what you described.

I've had a habit of putting the car in the on position a second or two before starting it to prime the fuel system. I started doing that though when it did take a little longer to start, which is frustrating since my whole ignition system is new (18k on wires, 15k on coil, 10k on plugs)

As I said I'll be getting a crankshaft position sensor from Ford, as well as the filler neck grommet thing. On that note, does anyone have a part number for that?

And any other reccomendations for fuel pump installation? I have the whole assembly here for the SVT focus, but VMP recommended reusing the stock sender and bucket.

I'm a bit nervous, namely because I've never dropped the tank, but I'm sure I'm just overhyping it.

RichV · Apr 16, 2013

I would toss a fuel pressure gauge on it, and take it for a drive to be certain. I did that with my SVO when I suspected a fuel issue. I have a diagnostic gauge that I just duct taped to the windshield and went for a drive.