RPM's keep dropping
#1
RPM's keep dropping
The last two weeks I've been noticing something odd.
When I start up the car and drive off, it starts and goes normally. Then I roll up to a light and stop. The rpms drop all the way down to 500 then up to 1000 then down again, and it finally settles in at 750 like normal. This happens a couple times then stops once I've been driving for a while.
It's a worse if I have the air conditioning on. It'll happen the same way but won't stop.
The only change to my car recently has been a new battery about a month ago.
When I start up the car and drive off, it starts and goes normally. Then I roll up to a light and stop. The rpms drop all the way down to 500 then up to 1000 then down again, and it finally settles in at 750 like normal. This happens a couple times then stops once I've been driving for a while.
It's a worse if I have the air conditioning on. It'll happen the same way but won't stop.
The only change to my car recently has been a new battery about a month ago.
#2
It could be the A/C kicking on and off, it could be the PCM making adjustments due to a poor signal from the battery or alternator. Everything is controlled by the PCM, something is obviously bothering it. Injectors could also be a little clogged causing variations in fuel mixture. When was the last time you changed your fuel filter?
#3
6th Gear Member
If you have your heating system on DEFROST, it also runs the compressor so that would act like the A/C was on.
#5
The fuel filter was changed 2 months ago - its been about 3k miles. I haven't used a fuel system cleaner.
Thanks for the quick responses guys. I'll give this stuff a shot.
If anybody got more idears keep em comin.
Thanks for the quick responses guys. I'll give this stuff a shot.
If anybody got more idears keep em comin.
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10-05-2015 07:16 AM