IAC problem......I think
#21
Great! Thanks for all your help, again. Next time it acts up I should be able to track down the source.
#22
One final follow up question, if I may. My car runs well now, most of the time, but once in a while dips but quickly recovers. Even though my IAC valve was cleaned and it opens and closes perfectly off the battery, is it possible for the springs inside to weaken with age and that combined with the pulsating signal cause a slow response?
#23
i would think weaker springs would cause it to open more rather than not enough, but since the idle circuit is a sort of servo feedback thing, the ECU should self-compensate
cracked hoses on on the idle air valve are definitely sources of excess air which can cause all sorts of running issues.
cracked hoses on on the idle air valve are definitely sources of excess air which can cause all sorts of running issues.
#24
i would think weaker springs would cause it to open more rather than not enough, but since the idle circuit is a sort of servo feedback thing, the ECU should self-compensate
cracked hoses on on the idle air valve are definitely sources of excess air which can cause all sorts of running issues.
cracked hoses on on the idle air valve are definitely sources of excess air which can cause all sorts of running issues.
#25
i would think weaker springs would cause it to open more rather than not enough, but since the idle circuit is a sort of servo feedback thing, the ECU should self-compensate
cracked hoses on on the idle air valve are definitely sources of excess air which can cause all sorts of running issues.
cracked hoses on on the idle air valve are definitely sources of excess air which can cause all sorts of running issues.
#26
#28
the LH 2.4 ECU remembers the optimal injection ratio trim based on monitoring the O2 sensor and MAF input air values and RPM. but even if this memory is forgotten, it comes up with a default map thats good enough, then refines it as you go through various driving conditions, and in just a few miles wil have relearned.
#29
the LH 2.4 ECU remembers the optimal injection ratio trim based on monitoring the O2 sensor and MAF input air values and RPM. but even if this memory is forgotten, it comes up with a default map thats good enough, then refines it as you go through various driving conditions, and in just a few miles wil have relearned.
#30
Thanks for that update. My 90 Regina car is doing the same thing and I was a Volvo tech for 30 years....go figure. I repaired that line several years ago, but it's time to look again. Now it's Jan. 2019 and the car is almost 30 years old. I also have learned that all of those multiplug connectors that use soft, rubber insulators eventually fail because the rubber insulators disintegrate and the barrel contacts back out. Goes for the suppression relay and the ECT plug, which I fixed last night.
--Paul Smith, Raleigh, N.C.
--Paul Smith, Raleigh, N.C.
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xDread92x
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11-19-2022 03:52 PM