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Discussion Starter #1
03 SPI

My car stumbles and loses power (literally) at low rpms (even idle) and around 50-60mph (2nd or third gear ATX). Dash lights remain on, sometimes the radio turns off, but A/C headlights and dash lights etc stay on.

When it happens the car stumbles, stutters a bit sometimes it loose total power (no power steering) sometimes it just stumbles, dash lights come on and tranny acts a bit funky then I am able to drive off fine.

I did a focaljet search, apparently there was a fuel pump recall but i dont believe on my model and year. I really want to change my fuel pump, but in reading the thread some said it was a possible EGR problem. Some (TXFO) said it might be a ECU problem.

How could I datalog to really get this problem pinpointed. I dont even know how to do it, but saw the term used many times before.

Does anyone have any ideas or possible solutions for this problem?
 

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Ever get any belt squeal?
 

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Discussion Starter #4
Talked with my friends who are techs at my local Ford Dealership. The informed me that it couldnt be a fuel pump problem becuase a CEL would be thrown if there was insufficient pressure.

They believe I have dirty injectors.
 

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CEL's are not always thrown when your car has a problem...

But it could be dirty injectors. If the car has inadvertently stalled there will be a failure record in the ECU for it. If you take it to a dealer they can look at the failure record and if they have any sense can tell what happened.

You could try unplugging the MAF sensor and seeing if it still stalls when you drive it. It will likely be hard to idle with it unplugged but it will drive. If it doesn't stall while driving down the road get a new MAF sensor.
 

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Discussion Starter #6
thats what was in the back of my mind as well. going to try that right now.
 

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Ok did it. Which was fine for about 30 minutes. Did some Drivablity test, was on the highway slow lane constant 65mph then went off into the stop and go of the city. It was fine, so I made the call to my local Autozone, just as I got of the fone with them guess what happened? It STUMBLED and died. However it wasnt as agressive as before it still had the same symptoms.

So going back the same route I disable the DPFE harness, so now both the MAF and DPFE are essentially unplugged. It ran fine again for 10 minutes then viola did the same stuff.

So not my conlcusion is, it most likely not the maf or dpfe. but there is still a possiblity it could be a EGR problem correct?

I pray its not a vacuum leak or injectors ($70 each).

Any ideas?

My friend who works at a Mazda dealership (way more experiance than the other two guys I know that work at Ford) was telling me that my symptoms that I described to him could be a number of things. Vacuum leak, Injectors (which he doubts), Fuel Pump (which he doubts), dirty MAF, DPFE, EGR, Cracked intake tube, Cracked coil, Plugs (which i already replaced), wires, PCM, etc etc.

There is only so much I can do at home with limited tool, the best would be to run a WDS (diagn.)

Untill I take it in tomorrow what else can I try?
 

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Check all your vacuum lines. If they are all snug, shoot some carb cleaner or brakleen or something around the throttle body, intake manifold and IMRC spacer in small amounts while the car idles.

Wait a bit after each shot and see if it stalls or if smoke pours out the tailpipe. If either one of these occurs, it's a vac. leak.
 

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Discussion Starter #9
did a vacuum check no smoke, at least i didnt see any. if i had a vacuum leak wouldnt I hear it as well?
 

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Possibly not. If it was small enough, I imagine it'd be difficult w/ engine noise.

A while back, I had a lot of small vacuum leaks. I never bothered checking for them because I couldn't hear anything. It was around my throttle body/intake manifold.

That's irrelevant, I suppose since you don't have throttle body upgrade or manifold upgrade, right?

If all else fails, let me know and we can work out the MAFS thing.

Rusty
 

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If you know someone with a fuel pressure gauge and a schrader valve adapter go see if you can borrow it. Hook the fuel pressure gauge up to the schrader valve and put the gauge under the hood and on the windshield, close the hood lightly so you don't pinch the hose. I usually clear tape the gauge to the windshield. Now go test drive the car, when it stalls out see if the fuel pressure drops. That will tell you right away whether it's fuel related or not.


If the EGR is sticking open making it stall there's an easy solution to this. While the car is cold, unplug the vacuum line to the EGR valve and plug the hose with a screw. Test drive the car, if your symptoms go away, you need a new EGR valve. You will likely get a CEL after a while though.
 
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