Idle surges
 

ok, i have been to my tuner 3x's. first time it stopped when i got there, 2x it was doing it, cold starts the idle will surge up to 1100rpm's come down to bout 700rpm's, i can feel it during drives on the highway when i let off the accelarator going 50mph 65mph, when i come up to a stop it feels like someone shoves me from behind, from the idle surges, my tuner has me drive around while he has the laptop connected to my obd, he cant find anything. my tuner is 47miles away, 95% highway, went yesterday, got there it wasnt doing it. anybody know what i can do to fix the problem. ?

supercharger?

Could be IAC. Could be a leak after the MAF. A gust of wind could cause a surge. My car did it from time to time in cold conditions and will cause my car to jump when I came to a stop. My car is an automatic.

sorry, forgot the most important. v-tech v3. 4.6lt 3v. 36k. All stock exept s/c and tune. i just find it strange that my tuner cant tell me anything definate. its gott be some kind of sensor right. ?

stanger, my gt is an automatic as well, after last night from driving home from work, i decided to cover it up and drive my "Hoopty" it sounds bad when it idles up an down, an when ur at a stop light an you know the car beside you can hear the idle jumping up an down between 700rpm an 1100 rpms, there has got to be an easy fix to this issue, granted i may have to replace some sort of sensor or tps or iac, i dont care, i just want to fix this embarrising issue. any suggestions from anybody.

will a dealership check this issue out if you have a s/c an tune on ur car ?
And why isnt this idle problem throwing some kind of code ?
like a light on my dash board. ?

Have you checked the connections to the supercharger and the condition of the air filter? Your MAF might be dirty.

If it only happens while the car is cold it may be worth a shot to leave the car at your tuners shop and have them look it over the next morning and test drive it to try and duplicate these conditions.

When my car did this when it was cold on cold mornings and lunge forward I called my tuner and told him what was up. He just said to bring it by and upped my idle a little bit and I never looked back.

just cleaned my maf, that didnt work. i have taken it to my tuner, and drove around while he sat in my pass seat with his laptop computer and my s.c.t. hooked up, he see's nothing wrong, number look good. now, two times i drove to my tuner's shop wich is 47miles away, all highway and when i got there it wasnt doing it, and just that one time when i did make it out there and it was doing it, thats when it was hooked up to his laptop, and the numbers he said looked good. do i have an i.a.c. housing that might need sprayed into with throttle body cleaner. ? btw, no MIL codes are being thrown.

The IAC should be bolted onto your throttle body. I am not all that familiar with a 3 valve but a quick search showed it on the throttle body.

You can disconnect that and spray it and see if it fixes your problem. It is worth a shot. If it fixes the problem but then comes back you then know the cause and know what to replace.

thanks stanger. just left my "NEW" performance shop, 30miles closer an ZERO traffic const. anyhoot, he drove with me today, hooked up his laptop we drove he looked at the #'s, all look good, he did notice some slight pinging when pedal to the medal, may pull sum time-n, tommorow. botoom line he says c/o, fuel filter&new plugs, have had plugs i engine for 3yrs, he said on s/c motors, they (Plugs) need to be changed out more sooner. so, wed morning going to him/tuner, an do these 2 c/o's first an se what happens. i let yall know how it goes, this cud b info 4 future people with idle/surging issues.

Copper plugs dont usually last long. I change mine every 6k miles. Fuel filter gets changed once a year. Let us know how everything goes with those changes.