Ford Focus 2004 manual 150K miles. Most days the car runs fine. Other days it will start and run until it warms up, then stumbles or hesitates at speed. When this happens the headlights and dash lights are also flickering. Sometimes i hear a clicking sound behind dash, left side. I have the sure cure: turn the heater fan to high. This works every time. When the engine is hesitating, i turn the fan to 4-high, the engine smooths out. Turn the fan down, engine again hesitates. Hesitates at 3, worse at 2, worst at 1. It seems to need the extra load. But after few minutes of high heater fan, the alternator light comes on. I flick the heater switch down, endure the hesitation for a few seconds, the alternator light goes out, engine still hesitating, flick the fan to high, engine smooths out.
A few months ago i could get it to fun smoothly with the fan on 3, didn’t need 4-high. Now seems to need 4.
On the days when it is always running smoothly, the heater fan can be on any speed, the alternator light does not come on.
Next few days or even weeks the engine will run smoothly, no hesitation, with the fan on or off or any setting.
The car has been to three shops in past year, one of them a major Ford dealer, who kept it two weeks. The problem has been diagnosed as battery (replaced), Battery connections (checked), plugs (replaced), fuel pump controller (replaced), fuel pump (replaced - ouch!), alternator (replaced twice - ouch twice), grounds (checked). Every time they “fix” something the car runs ok for a week or so.
OBD shows P2004 (intake manifold runner stuck) but all agree it can’t be the problem.
There have been a few times when i flicked the heater fan to high that all the dash lights died, fan went off, headlights off, turn signals didnt’ work, but the engine ran smoothly. Not so good on the highway at night!
There have been a few time, not recently, when the car wouldn’t start. No dome lights, no dash lights with key turned to ON, no clicking or starter with key turned to START. It acted as if my battery was missing. The cure was to turn the headlights on. All normal after that.
Hmmmm…why would all agree that the IMRC error can’t be the problem? It certainly could. The IMRC is an electronic module that operates what are roughly “secondaries” in the air intake system. It’s a set of butterfly valves on the intake that open up in the higher rpm ranges (somewhere over 3000K) to allow more air into the engine. If the thing does get stuck open it will cause problem down in the lower rpm range. So…I’m perplexed.
But, of course, even more perplexed by the thing with the blower fan. Give the P2004 and fan report, the first thing I would do, I suppose, would be to pull out a wiring diagram for the IMRC module and see if it shares anything with the blower motor circuit - maybe a shared ground or some such thing. Weird.
There is a loose or corroded electrical connection.
They just haven’t found it yet.
My first two guesses would be the connector to the alternator or in the fuse box.
I would also suspect a bad connection for a no start and I suspect it is in the ground circuit. I have had a battery ground cable that I had cleaned and tightened cause an intermittent no start. Didn’t find it until one dark night when I had the hood up when it wouldn’t start and I tried it again and saw sparks arcing between the ground post and cable end.
The trouble code could also be caused by a bad ground.
The reason I suspect this is that turning on the headlights let you start the car. Sometimes a medium load will help establish a ground for a large load.
Grounding seems the common theme. More info: I just talked with my brother whose Escape was showing symptoms of occasional hesitation. He said ford recall fixed a grounding bolt in ten minutes. Wish i’d heard that before my fuel pump and alternators
I’ll take it back to the dealer because they will be most likely to have diagrams to find all the grounding connections.
My Corolla has a heater fan ghost similar to yours. The back lighting for the heat control panel sometimes don’t come on when I turn the headlights on, but if I then turn the heater fan on, those lights come on … my solution so far is to just turn the heater fan on to get the lights to light … it’s a catch-22 tho as when it is dark it is hard to find the heater fan switch in order to make the lights come on … doh, it’s always something!!!
I agree with @circuitsmith , you’ve got a bad connection somewhere and the folks working on it just haven’t found it.
I’d start by taking my dvm out there and measuring the battery voltage at the dashboard while turning various things on and off, like the headlights, and the heater fan. No go? Then I’d do the same thing at the ECM circuit board and the IMRC.
btw, I also think that the IMRC diagnostic code is an important clue and shouldn’t simply be ignored as being unrelated.
the IMRC will not cause all that. It does not allow how much air gets in. It controls whether it takes a short or long path through the engine. This is changed to optimize low end torque and high end HP.
"the IMRC will not cause all that. It does not allow how much air gets in. It controls whether it takes a short or long path through the engine. This is changed to optimize low end torque and high end HP. "
I suppose its possible that the basic IMRC design changed between the 2.0L Escort and the 2.0L Focus even though the basic engine designs remained much the same. But either way, if the thing is supposed to be switching between the long and short position and it’s not, its implausible to say that it can’t affect driveability. There’s obviously an electrical issue at the root of all of this, but counting out a related IMRC problem is bizarre.
Who said anything about being left stranded? The complaint is about hesitation at high speed. Did you read this part: “hesitates at speed”? But you’re right - it’s odd to think that a device that affects engine performance could have anything to do with the engine’s performance. Silly me.
I’ve owned Fords since 1985 and won’t go to Ford techs because they’re too busy following SOPs handed down from corporate to worry about the real life weirdness of car issues. So while I appreciate the “Ford Master Tech” flag, I’m also reminded that it’s from the guy with the orange goo from Fram filters.
The OP says the car hesitates at speed but that this disappears with his blower fan on high, AND that he’s got a P2004. The fan connection is weird. All I said is that I’d look at a wiring diagram to try to figure out if anything is shared there - as a way of finding a clue to track down an electrical weirdness problem. There apparently is one - and it probably affects the IMRC, throws the code and gives the hesitation. But I guess without an officially notarized and sanctioned TSB handed down from corporate you wouldn’t be able to think about that.
if you are going to work in the car business, you have to have a sense of humor, or you will be miserable from listening to customer “concerns”. I’ve been on test drives with customers going the wrong way down a road, over a curb, etc. I’ve been pulled over in a cop car by a under cover cop because he thought I stole it. Had gun pointed at my head while I explained it. Loads of fun,
What always peeved me is when a customer brought a car in for you to evaluate, and didn’t like what you had to say
One time a guy brought in his car, which was in excellent condition, except the ac didn’t blow cold.
I charged the ac and added some dye. Soon enough, there was a green puddle underneath the car. It was coming from the condensation drain tube. I inspected the rest of the ac system and found nothing else. So I submitted an estimate for an evaporator, receiver-drier and a txv.
The customer was furious and complained to the service manager. He claimed I implied his car was a pos. He also claimed I was lying, and that there was nothing wrong with his ac. He said he’s not going to tolerate being treated in such a way. The service manager tore up the repair order, deleted it from the system, and told me to leave the refrigerant in the car!
So this dirtbag got a free ac recharge, and also found out exactly what was wrong with the system
Needless to say, I did not get paid for that job . . . because neither the customer, nor his car, were ever officially there
I actually laugh when I tell people about that story
I think pretty much everyone ends up on the short end of their manager’s bizarre overbearing rhetoric once in a while. One time I was in a business meeting, four staff members and our manager, and one of the staff said something that was supposed to be confidential between him and the manager. None of the rest of us said one word. We didn’t have time to say anything. But the manager stood up, yelled loud as can be at all of us, yelling “you shouldn’t be talking about that topic” , pointing his finger at us one by one “you don’t talk about it”, and “you don’t talk about it”, and “you don’t talk about it”, well you get the picture… we all just effected that “why you talking to me?, we had nothing to do with it” look on our face … lol …
"yeah, that’s why Ford is so big and successful. Just a bunch of retards sitting around drooling on themselves. "
I didn’t say Ford. I said Ford Techs. The leeches that try to latch onto you after you own the car. You know. The ones that can’t think their way out of a paper bag because they do nothing without a flow chart and computer to tell them what to do - but also the same ones who don’t give a rats tail because they get paid by the job - NOT by whether or not the job actually solves anyone’s problem.
@db4690, I got a better AC story for you. Had an early 90s Escort with a repair order stating AC not working. Pulled into shop. Opened hood to do initial visual inspection. Looking, looking, looking. This car does not have AC. Informed customer of this. They went bat sh** crazy and swore it worked last year and we were wrong.
