[Paul Middlemore]

I assume this has already been asked and answered but I can't seem to find a thread on it.

It acts like a misfire when accelerating. Basically a complete loss of power when accelerating in 2nd or 3rd, but then it comes back and will moments later sputter again. Repeats the process again after stopping and starting. Runs completely smooth at idle and eventually when up to speed will cruise at 70+ without a problem.

I started with thinking fuel, added an additive and pumped in 92 octane. Same problem. Changed plugs, no change. Changed wires and it improved but ended up with a misfire code, so I added dialectic grease to the inside of the plug wires and it improved. Today during a test drive it started again. During acceleration it acts like loss of power, comes back quickly, does it again, I shift to a higher gear, ease on the throttle and it may or may not stutter. I changed the coil tonight and the same thing happened during the test drive.

The only thing I haven't touched is the timing belt. It looked nearly new during an inspection but I may go ahead with replacing it.

Anyone have this condition and solved it?

 

[Paul Middlemore]

Hoping someone will jump in here; I have been all over the posts and although there is ton of information out there, I can't seem to find specifically what is going on with this darn car.

I forgot to add that I changed out the fuel filter at the beginning of this project.

What I have found today is the following: She acts like she is running out of gas and behold I got the Check Engine light code for PO171 System too lean (bank 1).

Most of the conversations (posts) that talk about this code, center around vacuum leaks, pvc valves and the like. i didn't find anything that specifically connected lack of fuel and this code. When I drive it and get aggressive with the throttle, she stumbles and cuts out, when I back off the throttle she recovers and if I lightly apply throttle I can get up to the next shift and so on until I am cruising at 70.

She idles perfect which kinda eliminates the vacuum leak although I sprayed a solution around the engine and didn't notice any difference.

So I figured I would test fuel pressure.............ah where in the heck does one hook up a pressure gauge on a 2002 SOHC engine. I can't find a location.

And then this happened. I went out to the shop to start it up and it ran fine and as I walked to the front, she started running poorly, idling terrible until she died. That hadn't happened before. I tried to restart and nothing; well she tried to start a few times but nothing.

So I pulled off the pressure regulator or sensor (I have heard two different identifies) that is located on the fuel rail and I got a small spray of fuel once I removed it. I did notice that the fuel continue to bubble with air for quite some time. I reattached it and it started right up and idled correctly, moments later it started running poorly again so I turned it off.

Where am I going with all of this? If I can't test the pressure then I can't positively identify that the fuel pump is going bad or extremely weak and since removing the fuel pump is quite the chore, I don't want to undergo the swap unless I have to.

I have no idea if my MaxiLink Code reader can show if the fuel pressure is operating correctly.

Anyone got or had something like this?

 

[Paul Middlemore]

Well hopefully either someone chimes in before I pull the trigger on a fuel pump and I might add, I am not looking forward to the fun of dropping the tank; even though the cut through the floor pan is enticing.

Some other notable discoveries. I decided to thoroughly check out the wiring harness in the areas pointed out in the threads as potential areas of wires shorting out. Upon unplugging one of the fuel injectors I found the well full of oil. Okay, no idea how someone gets oil in there unless they were pouring oil in from 10 feet up. Anyways, found all the wells with the same amount of oil. Thought I had found the problem. Cleaned all the connections and wells with electrical contact cleaner and the problem is still happening.

Figured out how to monitor the fuel pressure via my MaxLink Reader. Sitting at idle (850rpm) it is hanging around 16.10 to 17 PSI. Seems low to me as a document I read said it is supposed to be between 35 and 60 PSI. Every time it stutters, I see a drop in the PSI. When I try to drive it, it acts like I posted above, nearly shutting down and I have seen the PSI to drop as low as 2.5 PSI. Usually the problem is happening around 4 to 6 PSI.

In order to confirm I didn't have a faulty fuel gauge, I added two gallons to the tank (didn't want to add more as I might be lowering it) and I saw the reflection of the increase on the gauge.

Still problem exists with the additional fuel.

So I am narrowing it down to the fuel pump unless someone can tell me it is another part like the fuel regulator / sensor.

Any help would be appreciated.

Paul

 

[src153]

2002 pump is old. Why not replace it anyway as PM. If you replaced plugs, wires, and coil pack, seems like that would rule out a misfire. As for regulator / sensor, any guess is good as mine.

 

[Paul Middlemore]

Correct, I am leaning that way. I need to check out the FPDM (as another thread recommended checking that out, to ensure proper voltage is being supplied to the pump).

I am only assuming the pressure reading is low due to the pump and not the regulator / sensor. Since the code reader only says Fuel Pressure; kinda in the dark on what controls the reading.

Suck part is, I was planning on selling this car (nice car, interior etc....) and obviously in good conscious I can't sell it in this condition and then I would never own a SOHC engine again so all this knowledge will never be put to use again.

I am going back to Chevy and Ford with big blocks and carbs....................................................what I normally work on so this little beast has caused me more problems than I have ever had.

 

[src153]

I would drop the tank and clean it too. But that's easy for me to say. I don't have to do it.

 

[Paul Middlemore]

Right.....................might just have a look inside and decide on that one.

 

[Paul Middlemore]

Yep, replaced the fuel pump today and all the problems are gone. With just the key in the "On" position, it showed 23 PSI for fuel pressure. Upon startup, it went to 39/40.

Actually it improved the acceleration and pep of this little car.

 

[src153]

That was fast. Did your tank have a retaining ring at the bottom? MIne did. Had to be cut out.

 

[Paul Middlemore]

Nope, just some plastic press in clippy things on the sides, which allowed it to be pulled up.

 

[src153]

I've seen both styles on Youtube. Just wondered about yours. Sounds easier.

My 2001 DOHC had the bottom ring. You twist the assembly to release from the ring. But all the new replacement pumps are spring loaded and the ring gets in the way. The ring must be cut out for new install. The correct way is with Ford special tool. I've heard it can be done with diagonal cutters, but seems like putting a hand down in there would block your view. The special tool, designed for the job, makes it easier.

 

[Paul Middlemore]

I get it, best as I can tell there were two types, fortunately I got the easier one although the one you are speaking of seems better as it doesn't have that sock filter like this one did.

 

[src153]

My new replacement assembly has a sock too, but without the old retaining ring in the way, works fine.

Did you drop the tank, or cut a hole under the seat? Prospective buyers should be advised of a hole. Fire and explosion hazard in case of rear end collision.

 

[Paul Middlemore]

Yep you are absolutely right on telling folks what is up with the vehicle they are looking at. I might even keep the darn thing as it runs and drives nice for a 19 year old car.