Unresolvable Hesitation



I’ve switched the fuel pump on this car more than once and made sure the fuel line isn’t crimped yet it still hesitates. Also, the temp. shoots up when idling and appears to need either a fan or temp. switch? Whatcha think, guys? Many Thanks!


It surely would be nice to know the year…and mileage…and something about the maintenance history - things like spark plugs & wires, filters…in general whether the maintenance schedule has been followed & whether or not anything is due. It would also be nice to know something about the hesitation - like when it happens & under what kinds of conditions.

Why are you so sure this is a fuel supply problem? I’m going to go out on a limb and say you probably need a new coil pack.

As for the temp climbing at idle - yes. You need to find out whether or not the fan is kicking on. It would seem that it isn’t and you need to find out why. Start simply - check relays & fuses. If you find no issues, pull the cooling fan connector and jumper 12V directly to the fan. If it doesn’t run under a direct 12v then I’d start with a new fan. If the fan runs then you need to start going backwards to find out why the power isn’t showing up. A repair manual would be handy.


I posted that it’s an ‘01 Ford Focus. Only has 53K miles but I’ve noticed this hesitation since I bought it 8K miles ago. I previously suspected (as did my mechanic) it was a fuel pump-related matter since it seemed the car was hesitating more as the fuel level got just above empty, although just y-day it conked out on me with more than 1/4 tank, go figure. As such, the mileage in this lil’ two-door has been terrible, I’m sure this could be the result of the probable fan (or temp.) switch problem too. The fan kicks in after a long time which I’m told is common in these cars but it doesn’t seem right as the temp. gauge shoots up after not much time in city traffic. Any further insights are appreciated–thanks again!


Just found out too from my mechanic that he did a “scan” on my '01 Focus initially and that there appeared to be no issue with the coil pack. Also, he claims I don’t have a cooling fan connector with my car’s system. The fan does work, it just comes on late which, again, I’m told by Ford folks that that’s standard with my model.



I think you need a new mechanic. I don’t know where the '01 was in your first post - b/c it wasn’t. But during those years the coil packs in those cars are a known problem, and for many of them there is nothing about a scan that will tell you of the problem - depending on what kind of scan you mean. Did he actually put a scope on it? Or does the “scan” just mean a scan for codes.

You still haven’t explained exactly what kinds of conditions give you hesitation. However, one common way that these coil packs show their problems is at very low throttle hesitation - as in, you just step on the throttle to go, the car hesitates, stutters & then goes normally. This can go on forever with the computer picking up anything it thinks is a problem.

Another issue is that there is absolutely no need whatsoever to guess about a fuel pressure issue. You put a gauge on it and operate the car in a way that produces the problem while you check the gauge.

I also don’t know that it means to say that the fan doesn’t have a connector. The fan certainly isn’t hotwired to the battery so the is a place that it “connects” to the cars power. All of these things make me really wonder about the mechanic.

Find someone who will put a fuel pressure gauge on it, scope the ignition coil, and figure out why your fan isn’t coming on when it should.

One thing that could be wrapped up in there is your coolant temp sensor. If your computer isn’t getting good info about the coolant temp you may end up running too rich/lean at certain times. This can cause hesitation & could be wrapped up in temp at idle.

Basically, nothing you have here seems mysterious. It just sounds like you don’t have someone who is really worried about figuring it out.