IDLE question

[V10 MOJO]

im idling around 1700 in gear and outta gear until coming to a full stop then itll drop back down to "normal" that being around 500. the car did not do this after my heads/cam upgrade. it has started since i put the 70mm TBs on??

any suggestions?

 

[DarcShadow]

I've got a stock 2001 and it'll do that some times but not always. Haven't figured out why though.

 

[Gavin]

I believe with the 70mm TB's you need to locate a very hard to find Mopar High Performance Chip -OR, give Sean Roe a call and he should have an idea or two on the subject

 

[CMilViper]

Mine does the same thing on occasion, but not all of the time.

 

[Viper Specialty]

I have noticed mine always does it with the A/C off, but never with A/C on... Perhaps maybe a weather change around the same time you upgraded...and didnt notice?

 

[PaViper]

Mine does that too on occasion....I try not to think about why

 

[JonB]

im idling around 1700 in gear and outta gear until coming to a full stop then itll drop back down to "normal" that being around 500. the car did not do this after my heads/cam upgrade. it has started since i put the 70mm TBs on??

any suggestions?

I think I recognize that as a 1999 RT ?

"IDLE HANG" is the issue. Search IDLE HANG

My guess is that you no longer have an OEM airbox? I hope you stayed away from the droop-snoot hangey-down HOT AIR INDUSTION CONES !!!

The IAC-ISM has 26 electronic 'steps' to drop the idle back down to either #5 or #7.....The Year Matters. That valve needs to have SOME intake vacuum to it to act properly. Folks who just stick an itsy-bitsy air filter on it can have this happen, due to TOO MUCH FLOW! On the OE hose from the airbox, just inserting a restrictor or clamping the hose mid-hose by 30-50% can fix idle hang. If no hose, use a smaller filter on the end of a restricted hose/inlet.

And keep the valve itself clean....

Other ideas....When the car is HOT only? .... the wiring harness at the IAC-ISM connect itself, left-rear corner back by coilpacks.... BE SURE CONNECTIONS are clean and insulated. HOT HEADERS can damage this connection, change the resistance, the idle is screwy. Guys can change the ISM and get no benefit.....because its the harness ! Clean the contacts.


"Normal" idle is 750, there is no 1st hashmark on the tack making it look like 500...

 

[JonB]

I have noticed mine always does it with the A/C off, but never with A/C on...

Grasshopper...... wanna know why?

Anyone with idle probs can simply turn on the A/C and the problem usually goes away. Why?

Because A/C-ON trips the PCM into a constant adaptive idle mode, to be able to accomodate the compressor cycling. So, OTHER problems are 'fixed' by the adaptive being ON.......thanks to A/C being ON.

Go, and spin no more.................

 

[V10 MOJO]

well, just got it back from the garage; Everything checked out fine, IAC, PCM TPS and anything else on this damnn thing. bottom line is; i put on 70mm TBs and a mod airbox and now the damnn cars idles like its on crack.

My solution, im putting stock TBs one and these stupid asss accufab hunks of metal are going on ebay.

 

[Bob D]

Try unplugging the computer. If you didn't re-set it when you installed the 70mm's , that could be the problem.
I used to have idle problems before I installed my Roe SC last year. 6000 miles and it's been idling perfect. Go figure !!

 

[V10 MOJO]

ive done everything possible except takin em off, melting them down and shipping these pieces of shiit to guatemala!

i cant believe that there isnt something that can be done. its like the lean/rich thing, is this yet another example of fine engineering at its best??

 

[99 R/T 10]

Rich, you big wennie! Just stick a restrictor infront of the IAC. The thingy on the right front side of the intake that is suppose to be connected to the air box.

Mike

 

[newredrt10]

Do what they said about the restrictor. I had the same problem and everyone around here said everything was good. I put the restrictor in and all was fine. You might want to take another look at the 70mm setup. They really don't help until the higher rpm, they could even hurt the lower end.

 

[Sam Goldfarb]

I have recently had the Idle Hang problem show up on my
97 GTS. I like the cruise control effect on the highway,but it can surprise you when you downshift to slow down and actually speed up!I put a piece of 3/4"steel rod with a 21/64" hole in the small hose leading to the idle control valve. It dropped the 1800 RPM hang down to about 1400 and then it seems to drop to about 600 RPM a lot quicker than it did. I haven't tried the AC trick yet and still have to road test the thing. The problem first appeared after I had a dead battery. Even after recharging and re-learning the computer it has randomly appeared a couple of times. Hope the above trick works. I was told that the 21/64" hole is a starting point and it may need to be a little larger when AC and headlights are on. I can live with a lower idle, it's easy to rev the motor, but you sure look like an idiot when you are at a light reving your engine 2500- 1800!!

 

[JonB]

BUMP for Tony

 

[Larry Macedo]

Rich,

You can actually install the TPS in (2) positions on the TB's. The 1st position will be roughly 16% or under 1V and the other will be 36% or over 1V @ idle. I suspect the TPS may be on the latter of the two. When indexing the TPS, it will only roll slightly whereas if it's on the 2nd position it will roll quite a bit before the holes line up on the TB's. Do you get a check engine light?

 

[Larry Macedo]

Or you may need to orifice the IAC hose...

 

[Larry Macedo]

Or the base idle adjustment is off on the Accufab's...

 

[ACELLR8]

I am trying to follow this problem myself as I just completed a total motor rebuild with new K & N airbox. I now am having the same idle problems as V10 MOJO.
What is the IAC? I know there is two hoses going to the airbox, which one is the likely suspect? Passenger side one or drivers side one?

Thanks,
Ed

 

[dansauto]

hey bonehead, IAC is the idle air control its the pc with a tube and black plastic pc on you intake manifold with a tube connecting it to the airbox. Make sure its not sucking air under the gasket

 

[ACELLR8]

hey bonehead, IAC is the idle air control its the pc with a tube and black plastic pc on you intake manifold with a tube connecting it to the airbox. Make sure its not sucking air under the gasket

Don't ************ up there and kick your A$$, I am sure it is this piece of Shi t airbox you sold me causing me all this stress.

 

[dansauto]

worked fine on my car, it probably flows too much air for your 10 cylinders running on 8...