Drop in RPM while stopping?
#1
Drop in RPM while stopping?
My 07 H3 w/ I-5 drops in RPMs down to the 200-300 range and feels like it's going to stall when I am almost stopped. It will also do this when I'm in park and rev it up. When the RPMs are on the way down, it drops to the 200-300 range, feels like it's going to stall, and then pulls up into the normal idle range. What seems to be the problem??
#3
That does not sound normal. I would get that diagnosed and fixed before getting the tune. You wouldn't want to get a tune and still have some underlying problem. I got the PCMforless tune and it made a world of difference in drivability. Good luck.
#4
Funny thing, this is now happening on my 06' H3. The last thing I remember doing to the truck prior to me having the same issues was, change out the Air filter to a K&N filter, and also change out all the spark plugs.
Does anyone know why the RPM's drop like this, and also make it seem like it's going to stall?
Thanks.
Does anyone know why the RPM's drop like this, and also make it seem like it's going to stall?
Thanks.
#6
I installed the Spark Plugs myself, they were brand new out of the box. I don't think they are misfiring or anything because I don't think it would cause that kind of problem even if they were...
Anyone else?
Anyone else?
#7
leak in air intake
only a guess but my ford probe did this when the rubber boot feeding the air intake(mass air sensor)?
i had to hit the gas, mainly till it got hot.
strange but i think an air leak AFTER that point speeds it up, like opening the throttle. some guys spray water on those areas to see if it seals up and changes rpm
just a guess
tom
ps the probe was a turbo, but at idle i dont think the turbo had any effect,,,???
i had to hit the gas, mainly till it got hot.
strange but i think an air leak AFTER that point speeds it up, like opening the throttle. some guys spray water on those areas to see if it seals up and changes rpm
just a guess
tom
ps the probe was a turbo, but at idle i dont think the turbo had any effect,,,???
Last edited by drtom; 12-01-2009 at 01:08 AM.
#8
What actually matters is......ta da....... the truck does not actually stall, you just assume it feels that way. You know what happens when you assume something.
The PCM in the 3s has fuel consumption management strategies programmed in to lower your rpm as low as possible, and shut off the alternator output, when it senses you halting the vehicle, and there is no need for additional electrical output. The process reins in the rpms very low until it senses that the timing needs advancement and throttle needs to bring the rpms back up to normal idle. There is a slight lag, this is normal, but is some vehicles you may notice it more than others.
It will NOT allow the engine to stall and has NOTHING to do with intakes or filters. It is trying to save fuel when you are coming to a stop, and it will do it in forward and reverse. There are several other aspects of this same fuel consumption management, but they do not relate to this question.
The PCM in the 3s has fuel consumption management strategies programmed in to lower your rpm as low as possible, and shut off the alternator output, when it senses you halting the vehicle, and there is no need for additional electrical output. The process reins in the rpms very low until it senses that the timing needs advancement and throttle needs to bring the rpms back up to normal idle. There is a slight lag, this is normal, but is some vehicles you may notice it more than others.
It will NOT allow the engine to stall and has NOTHING to do with intakes or filters. It is trying to save fuel when you are coming to a stop, and it will do it in forward and reverse. There are several other aspects of this same fuel consumption management, but they do not relate to this question.
#9
What actually matters is......ta da....... the truck does not actually stall, you just assume it feels that way. You know what happens when you assume something.
The PCM in the 3s has fuel consumption management strategies programmed in to lower your rpm as low as possible, and shut off the alternator output, when it senses you halting the vehicle, and there is no need for additional electrical output. The process reins in the rpms very low until it senses that the timing needs advancement and throttle needs to bring the rpms back up to normal idle. There is a slight lag, this is normal, but is some vehicles you may notice it more than others.
It will NOT allow the engine to stall and has NOTHING to do with intakes or filters. It is trying to save fuel when you are coming to a stop, and it will do it in forward and reverse. There are several other aspects of this same fuel consumption management, but they do not relate to this question.
The PCM in the 3s has fuel consumption management strategies programmed in to lower your rpm as low as possible, and shut off the alternator output, when it senses you halting the vehicle, and there is no need for additional electrical output. The process reins in the rpms very low until it senses that the timing needs advancement and throttle needs to bring the rpms back up to normal idle. There is a slight lag, this is normal, but is some vehicles you may notice it more than others.
It will NOT allow the engine to stall and has NOTHING to do with intakes or filters. It is trying to save fuel when you are coming to a stop, and it will do it in forward and reverse. There are several other aspects of this same fuel consumption management, but they do not relate to this question.
Ultimately, if your first answer wasn't the right answer to this problem.. Could there possibly be another issue we might be overlooking?
Thanks for your time, Doc.
-Stavros