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View Full Version : Friend's 2002 Focus Ztec 2.0 idle issues



FaultyMario
January 11th, 2014, 12:31 PM
Won't start when cold. Mechanic 1 says it's the fuel pump assembly that needs to be replaced. Tested pressure before injectors and got numerous readings other than the 40psi he says should be the norm for that car.
Mechanic 2 says to disconnect Fuel (pressure?) regulator and if car then starts and maintains idle, then it's not the fuel pump. Friend did so and, alas, car idles, albeit a little faster to my ears (I'd venture and say it idles between 1500 and 2000 rpm).

Two sensors have been "replaced" one is the Crankshaft position sensor, which was broken/damaged at the base and tip, and another sensor that looks like pitot tube but it's made of bronze with a 6" extension to the connector, mechanic says it's coolant temperature sensor. The verb is in quotation marks because my friend only bought one of the sensors, so he's wondering how the mechanic swapped 2.

Any idea what it could be? any known problems with that engine?, the engine sounds make it seem like it could be a fuel delivery/ mixture-management issue at the electronic level as the car chokes when not warmed up. But mechanic #2 thinks it might be an air leak in the system.

thesameguy
January 11th, 2014, 01:48 PM
My recollection is the Zetecs on Focii are returnless fuel systems and a pressure sensor modulates the regulator. You should see very close to 40psi under all conditions, although fuel pressure on these cars is known to drop off under really heavy load causing starvation in the last couple cylinders. Bad news for Zetec turbo kits. Is there a check engine light or anything? Any other symptoms of this problem other than crap cold starting and running?

FaultyMario
January 11th, 2014, 03:20 PM
CEL has been on for 2 or 3 years, but this problem showed up about a month ago.

He is hesitant to buy the pump and accessories because of cost, he doesn't want to buy something expensive that won't solve the issue. He's even more scared of taking it to the Ford stealership for a scan, as his mechanics OBDII come out empty handed.

Also he wants to be sure of what exactly he's disconnecting when following the advice of mechanic #2. It's located very close to the surface right around the yellow circle in the attached image.

thesameguy
January 11th, 2014, 03:58 PM
It's been a long time since I did anything with a Zetec, but I don't think that's the fuel pressure regulator. I *think* that is a damper. The regulator should be attached to the fuel rail, and it doesn't look like a conventional fuel pressure regulator, because it isn't. It's a sensor thingy that feeds data to the fuel pump control circuitry. The damper is there to smooth fuel flow as the pump adjusts rail pressure.

I'd start with that code - you're going to need it. The symptoms you have and the diagnostics suggested could be the result of some other problem that's either generating a response (like limp home) or other symptoms. It could very well be a scenario like:

o CEL for lean mixture due to a small vacuum leak
o vacuum leaks gets big resulting in a no-start
o messing with the fuel pressure control circuitry nets a rich mixture which overcomes the vacuum leak and starts the car

In fact, I wouldn't be the least surprised to find out that's exactly what's going on.

I don't think you have a fuel pump problem, personally. If the car runs once warmed up, that points the finger at a mixture issue - either a vacuum leak, a failed MAF (MAP? I don't remember!), or a goofy temp sensor.

FaultyMario
January 11th, 2014, 05:14 PM
Ok, info relayed.

Thanks, TSG.

Drachen596
January 11th, 2014, 05:39 PM
fordparts.com

if you can find the part on there they typically include a clickable diagram. its come in handy when i've been trying to figure out a couple things on my Crown Vic.

FaultyMario
January 30th, 2014, 07:51 PM
You were right, Justin.

Well partly right, or mostly right. FPR is not a regulator, actual regulator sits somewhere within the fuel pump. Yes, mechanic #2 fiddled with the engine by bypassing the FPR which in turn caused it to run rich. Running rich hid the vacuum leak.

Thanks, mang.

thesameguy
January 30th, 2014, 08:53 PM
Returnless systems baffle lots of mechanics, no real surprise there. The Zetec was one of the first fuel injected motors to do that, but in '14 it's more common. Dudes should get on the bandwagon. ;) There really isn't a regulator on those motors - the fuel pressure sensor on the fuel rail feeds info back to the ECU, which varies pump output through PWM, just like how a computer fan's speed is controlled by the BIOS, or how the Fiat moves at all. :D