I just started having issues with my 2003 Ford Focus ZX3 2.0. I turn it on and it’ll crank. Sometimes it turns on and sometimes I gotta give it some gas to turn on. Once its on and I let go of the gas it goes down on RPM and turns off. I press on the gas and hold it to about 1000 rpm it’ll stay on. If not it shuts off.
I recently replaced the starter, battery terminals and cables. I don’t think it has anything to do with it but I also have a new AC compressor in there.
I did some research and may be a couple of things such as the MAF sensors, Fuel regulator, and possibly air intake. Not sure but want to get opinions from others to see what the problem may be so I can fix it.
It is likely either an ignition or fuel issue. It could also be a sensor failing or disconnected that is leading to one of the other issues I mention.
Are there any check engine lights? If so read the codes and report back. If there are no codes I would be thinking it is electrical in nature and start checking all grounds, especially those anywhere near where recent work was done.
How long has it been since it was tuned up last? How many miles?
This may be that Ford SPI engine that so many people have issues with. That is usually a catastrophic engine failure resulting from failure of the valve seats and likely has nothing to do with your problem but is something to consider before dumping lots of money into this. This may be a $10 for for all I know but if you get into big money, it might be time to move this one along.
No way to diagnose without more info. Need to know if check engine light is on, and if so what are codes. Second when it runs with foot on gas, does it run smooth, or rough?
Let’s keep it simple and prioritize. It could be anything mentioned in this post,but we need to find a way to figure out which one. Seeing as there are no active codes, let’s move sensors down the priority list. Fuel problems often cause problems like this and won’t throw codes. So that’s where I would start. A fuel pressure gage would be handy and they’re inexpensive, but may not be necessary. First try this: with an assistant near the gas tank, turn the key to the run position (not the start position). You or your assistant should hear the fuel pump run for 3 to 5 seconds. If you do that’s good. Then turn key off. Then turn key to run position again for 5 seconds. Repeat this 2 or 3 times, then try starting car with foot off the gas. If it starts and runs for a little while, and you heard the fuel pump whine every time you cycled the key the problem most likely is restricted fuel Flow. This is the time you would use a fuel pressure gage to confirm this diagnosis. If you’re not going to get a gage I would next change fuel filter.
Sorry for the late reply everybody! So this situation happened right before I went out of town. I was going to take this car out of town but due to the problems, I didn’t. When I returned, which was the next day, I got in the car and it started right up with no problems. I tested the MAF sensor while it was on. While it was on I disconnected the MAF sensor and it stayed on. So that I know i need to replace. While I was checking the engine area, there was a little hose that went from the Air filter to the engine (Not the Air Intake), it was disconnected from the air filter side. Once I put it back, I turned off my car and turned it back on a couple of times to made sure it started right up and stayed on. Which all times it did. All in all, it was that hose that needed to be put back in and I need to replace the MAF sensor.
That’s probably part of the pcv system. If there’s a leak in that system – such as from a disconnected hose – it will cause the engine to run lean and may cause all sorts of drivability problems. I’m not convinced this has anything to do w/the MAF or that your MAF is faulty. Suggest to let us know in more detail why you think that, b/c replacing it may not solve anything and result in more unknowns & a big expense.