RPM's consistent?
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Tuned
Joined: Feb 2003
Posts: 451
Likes: 5
From: Raleigh, NC.
RPM's consistent?
Not sure if this is a problem or not.....
Noticed the other day, when holding RPM's at let's say 1500 steady in park, every few seconds, the rpm's will dip down about 250 for a quick second and return to 1500. It seems this is some sort of cycle as it will repeat maybe every 45 seconds or so.
I am not sure if this is normal or might be showing some sort of sign to a problem?
I put it at 2000 rpm's and held steady and it will do this same cycle. Once the engine warms up a bit, the dip in RPM's is less, like maybe 150 rpm's dip and back to steady 2000.
Anyone every try it? When doing the alternator test at parts store a while back, I noticed it did this so retried after new alternator and it still is doing that cycle.
Noticed the other day, when holding RPM's at let's say 1500 steady in park, every few seconds, the rpm's will dip down about 250 for a quick second and return to 1500. It seems this is some sort of cycle as it will repeat maybe every 45 seconds or so.
I am not sure if this is normal or might be showing some sort of sign to a problem?
I put it at 2000 rpm's and held steady and it will do this same cycle. Once the engine warms up a bit, the dip in RPM's is less, like maybe 150 rpm's dip and back to steady 2000.
Anyone every try it? When doing the alternator test at parts store a while back, I noticed it did this so retried after new alternator and it still is doing that cycle.
More Turbo
Joined: Jul 2010
Posts: 535
Likes: 13
From: California High Desert
You may have thought of this already, but is the A/C compressor coming on? The only reason I thought of this is because the A/C runs in all but a couple HVAC settings, too many of them IMO. Sometimes I think it would be nice to have a simple A/C on/off button like my Nissan and T&C do to shutt off the compressor despite the position of the controls.
Elder User
Joined: Feb 2006
Posts: 545
Likes: 5
From: FL
You have not mentioned if there is a surge in free idling, it should be steady 750-800 rpm . Northwindone suggested the cycling of A/C . You can turn off the A/C entirely and get it out of the equation, see if you still have the surge .
If you still have the surge , you can do some DIY items first , like cleaning your MAF and throttle , changing fuel filter & air-filter ( if not done recently) and run a good injector cleaner thru the system . Also check if there is any vacuum leak at PCV hoses ( the plastic 90 -elbow and rubber elbow on throttle ).
good luck,
If you still have the surge , you can do some DIY items first , like cleaning your MAF and throttle , changing fuel filter & air-filter ( if not done recently) and run a good injector cleaner thru the system . Also check if there is any vacuum leak at PCV hoses ( the plastic 90 -elbow and rubber elbow on throttle ).
good luck,
Thread Starter
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Tuned
Joined: Feb 2003
Posts: 451
Likes: 5
From: Raleigh, NC.
There is no surge at idle. No accessories are running so compressor is off.
I never notice it when in gear. I am wondering if anyone here can try this test and see if there's does it also? Maybe this is just the computer doing it since it is not under load.
Just want to rule it out.
MAF is clean, did it recently and also cleaned filter. I also ran some Amsoil PI fuel injector cleaner through an entire tank and that removed my pinging that everyone else was mentioning a while back. I noticed a long while back, this was happening but thought it was normal.....and maybe it is. Just want to rule out an issue if it is one.
Hoping someone here can check and see if their V10 does the same or not.
Also, my Yamaha outboards only run on 4 of the 6 cylinders when in neutral and have rev limiters so when in free load, they have computer controlling them.
I never notice it when in gear. I am wondering if anyone here can try this test and see if there's does it also? Maybe this is just the computer doing it since it is not under load.
Just want to rule it out.
MAF is clean, did it recently and also cleaned filter. I also ran some Amsoil PI fuel injector cleaner through an entire tank and that removed my pinging that everyone else was mentioning a while back. I noticed a long while back, this was happening but thought it was normal.....and maybe it is. Just want to rule out an issue if it is one.
Hoping someone here can check and see if their V10 does the same or not.
Also, my Yamaha outboards only run on 4 of the 6 cylinders when in neutral and have rev limiters so when in free load, they have computer controlling them.
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