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Question about ford IMRC

I have a ford with a 3.8L engine. There is a vacuume controlled butterfly valve on the intake manifold that opens and closes based on engine RPM. The system is called Intake Manifold Runner Contorl (IMRC). Its supposed to give better torque and smoothness by adjusting the characteristics of the intake manifold. Mine seems to have a leak in the rubber manifold, so it no longer works.

I haven't noticed any difference in the performance of the engine, but it does turn on the check engine light with an error code 1537 & 1538 ( bank

1&2 stuck open ).

Ford wants $350+ just for the part!

Will the engine still pass and ODB2 emission test with this code? Is there any way to "fool" the computer to not give the error code?

Reply to
Jack
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The short answer to your test question is probably not. In test areas with which I am familiar, the emissions test is nothing more than reading the ECM for fault codes. Some have additional testing. Any fault code or if the light is on, it will not pass. Also, you are not likely able to "reset" the ECM to clear the fault codes and pass. This is because the vehicle has to go through a number of operational cycles for the ECM relearn the vehicles operating parameters to set the required readiness flags. The original fault code(s) will most likely be re-generated during this time.

If you are handy with the needed tools, you may be able to get an aftermatket manifold at a much lower price then the dealer.

Lugnut

Reply to
lugnut

Sure, rig the sender to send the proper mili-volt signal to the microprocessor to indicate it is in normal position and not stuck open. My guess would be between nine to eleven mili-volts, or perhaps it is as easy as sending anything BUT 1 or 5 volts

Reply to
Mike Hunter

That might work but on my S-10 when I wanted to disconnect the EGR to see if it was causing problems I discovered that at seemingly random intervals the ECM sent the "wrong" signal to the EGR to see if that would momentarily change the rpm. If no change occurred it set a fault code. I found this info somewhere in the service manual. This ford may do the same to test for operation and if it doesn't move and cause an rpm change it would set a fault. Just a possibility.

Reply to
Ashton Crusher

I did some playing around with the IMRC valves. The system only complains when the valve is in the stuck in the "open" or default position ( held by the spring ) generating the check engine light & 1537 code.

The valve should be closed at idle and in low rpm when vacuume is applied to it. I wired the valve closed and the code went away. The second IMRC seems to work fine when I plug the hose going to the bad IMRC. It seems to idle a bit smoother. Not sure how much higher rpm power I am losing, but I haven't noticed any difference.

Reply to
Jack

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