Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

2004 Ford Freestar IMRC problem

Have a vehicle that all symptoms points to the IMRC ( vehical chugs like it is not getting fuel, intermittent) and no one can identify ( 3 mechanics alread) originally car had spark knock and sometimes smell of sulfer. Smell gone, imrc “supposedly repaired” replaced the Ignition coil pack and no Error codes have been logged, check engine does not lite.

Fragments of information are just confusing. Start at the beginning. Provide the sequence of events including symptoms, computer codes and repairs. Mileage and maintenance history would also be imperative. Seriously - you’ve had 3 mechanics look at the car - we know nothing of the history and can’t put hands on it ourselves - you need to do better.

What makes you think about the IMRC? That would produce air problems, not fuel. What was “repaired” about it? Why was the coil pack replaced?

For life of vehical, regular routine maintenence never an engine problem. @ 118000 miles, experienced spark knock,(reduced with higher octane fuel) and sulfer smell. Engine light would illuminate occasionaly and then shut off.

  1. The following is from the repair bill @118000 miles. Mechanic troubleshoot, computer stored errors - P0171 B1 lean, P0316 misfire, P0303 #3 Cyl misfire. Checked for vac leak- none, check egr, resistance ohm test injectors/OK. Replaced Ignition Coil Pack & Spark Plugs. @ 121000 miles i took vehicel back because i was experiencing new issue which occurred shortly after the repair at 118000 (due to holidays the delay taking back to repair center)
  2. While driving at any speed between 30-55 at steady pace vehicle would jerk/chug (not violently though). Experienced same when flat roadway goes into a rise (hill) at just over hill when vehicle would idle back the car would chug. . Repair center couldn’t duplicate the chug, after research with Ford, TSB 17-16-17, claims to have found clips on the lower intake IMRC linkage rods Broken, replaced and checked for VAc leaks and air flow sensors, no problems ( i did question this diagnosis). There were no stored error codes in computer and the Check engine light never illuminated.
  3. with in days, vehicle chug again and again and again. Returned to mechanic, they could not duplicate, and decided to replace all 6 spark plugs (were replaced @118000 miles with ignition pack). From this point on I never experienced the issue again until @ 139000 miles while driving at 55mph, vehicle chugged and no Check engine light illuminated. During the 500 miles before i could get into a Ford Dealer for repair, vehicle chug occasionally and once the red Engine light (not check engine) flashed and only once. Took vehicle to Ford service and they could not duplicate problem. No error codes to read from computer.
    I submitted info for assistance to Just Ask and was given the same conclusion that the IMRC was area to look at in detail.
    I hope this additional info is of assistance to you

I don’t know that I would be thinking about the IMRC. This will be active only at high rpms (I think it opens at about 3500) - like under hard acceleration. When it has chugged has it always been directly after hard acceleration, perhaps? I suppose it could be getting stuck open on occasion and that would cause a lean condition. It may be worth a trip back to the shop that replaced the rod linkage to ask them to double check their work.

But really, I’d be looking at much more basic things - such as the fuel filter. Has it ever been replaced? I also wonder about the spark plug wires - the plugs and coil pack were replaced - have the wires ever been replaced?

The engine ran without a problem for thousands of miles, each time, after the spark plugs were changed. Is this a red herring, or useful clue? Were the spark plugs inspected when they were changed? A skilled mechanic can read the spark plugs and make assumptions about how the engine is running.
Have the spark plugs inspected/replaced. How do the old spark plugs look? An engine which burns too rich, burns oil, burns antifreeze, can cause the spark plugs to foul.

thanks for reply
fuel filter had been replaced at about 100k mark with some regular maintenence, oil, trans oil etc. Chug never occured after acceleration. Supposedly when i took vehicle back to original shop when the finally replaced the spark plugs the claimed to have double check the IMRC linkage work.
Wires have never been replaced. Probably worthwhile to do that due to mileage age.

Add on to new wires having the fuel pressure tested - but it needs to be tested under load. This can be simulated by watching pressure as the engine is revved, or a long hose can be rigged to watch fuel pressure while driving. Of course, it does seem to be an intermittent issue - these are very hard to track down.

Is there any possible connection to dampness? Rain? High humidity? Make sure the new wires get boot grease.

its not a weather issue,
I plan to go the new wire route and see what happens from there

I am haveing the same problem. what was the final solution to your problem?