simpleboy77

iTrader: (10)

Here the problem. I can start the car and it iddle fine. I can rev it and it back to normal. On the road, in all gear the car run a 1.5-2k rpm (if I dont tuch the gas)and when I stop at a stop sing or light, it take 2sec and the rpm drop at a normal iddle. It do the same thing if I but the car in neutral until I stop.

Car have ben tune whit HP tuner whit true duals, no cats and no X by the other owner. Now it have a Y pipe + hight flow cats (need to pass safty check) and the rest, untouch. Rear O2 is delete.

You think I need to retune the car ? I have no check engine light.

Car is 2001 Trans Am 6spd whit all bolt on (include head and cam)

Thanks

2001CamaroB4C

iTrader: (11)

until you shift it out of gear its gonna stay at whatever rpm you left it at, it may drop a little but not much.. if you want it to drop to idle while driving, get it out of gear.

simpleboy77

iTrader: (10)

Ok, I can give a better example. I'm in 3rd gear, as soon as I press the pedal clutch to the floor, The RPM will drop and stay at 2K. When I completly stop the car it will stay at 2K for maybe 2-3 sec and drop bellow 1K.

One more ? If I'm going, let say 30mhp, put the car in neutral position, same problem. The car will run at 2K until I do a complet stop .

Dan Stewart

Sounds like you need to adjust one or more of the following:

Idle airflow
Idle timing
Throttle cracker

This is common when you put in a cam.

Check out the PCM section here for more info.

simpleboy77

iTrader: (10)

The tune was done whit the head and cam. I just put a post on PCM section too.

Thanks

ZeroFear

iTrader: (1)

sounds like it didn't get tuned good if something like that is going on.

therealcreeper

iTrader: (37)

i'm surprised you don't have a high idle code or anything

i had similar problems recently. replaced the pcv valve and intake manifold gaskets and now it's gone. check for vacuum leaks and have the tune looked at.

lovin myls1

iTrader: (4)

Maybe vacuum leak?

"Too fast an idle speed. The powertrain control module (PCM) will maintain normal idle speed and compensate for a small vacuum leak by closing down the throttle body air bypass. But if the leak is too large and the idle control system cannot compensate for the extra air, the engine may idle too fast. Common leak paths include the throttle body gaskets, intake manifold gasket, any of the engine vacuum fittings, hoses or vacuum-operated accessories (such as the power brake booster or EVAP canister purge valve). It is even possible that leaky O-rings around the fuel injectors may be allowing air to leak past the seals. Another overlooked item can be a worn throttle shaft".

simpleboy77

iTrader: (10)

Is there a way to check for vacuum leak ? Any special tools or just do 1 by 1 and look for loose fitting or crack? I have a vacumm gauge from autometer but its mécanic and if I had a leak, the presure will be down.

I just found out its only doing this when hot. I can drive maybe 5 min before its start to do this.

lovin myls1

iTrader: (4)

Yes there is.Here is a link about missfires caused by vacuum leaks as well as other things and how to test for them.Notice the EGR valve info also, as that causes problems as the car temp changes.Here is the link,hope it helps:http://www.aa1car.com/random-misfire/

simpleboy77

iTrader: (10)

1/2 problem solve. Well kind of. After many search on here and the web, I found the IAC can be defect.

I did a test and unplug the sensor. I was idleing at 2K and when I unplug the IAC, the RPM drop to 1.5k.

The search will continu .

therealcreeper

iTrader: (37)

IAC's don't really go bad too often. i thought that might be my problem too but it ended up being a vacuum leak. check for them first.

simpleboy77

iTrader: (10)

I check for vacuum leak. I'm at 15psi at iddle. On the post 7 , you change the intake gasket and the pcv valve and your problem got solve. I try to change the pcv. Its a cheap way to find if this the problem or not.

Maybe the intake manifold gaskets have small leak but this is hard to test. Propane torch or carb cleaner can help to detect the leak. I will try that this weekend.

simpleboy77

iTrader: (10)

WOW, I got a SES yesturday P0507 (idle air control system RPM higher than expected). I clean up my TB and 1 hour later the SES light came up.

I did a search again here but all have the exact same problem but no one have any uptade if there problem was solve.

Here a check list I just made based on other:
- Vacuum leak
- IAC defect or have to be clean
- TPS defect or have to be clean
- Clean the maf
- PCV
- Intake leak (retorque the intake or change gasket)
- TB Gasket leak (retorque the TB or change gasket)
- TB ported to close to the throttle blade
- TPS grounding issues and/or dirty electrical contacts at the TPS or PCM
- Tunning not done right

simpleboy77

iTrader: (10)

Ok, I know its a double post but I have fond 2 thing.

1- I unplug the TPS and car run perfect. The RPM drop every time but my TCS is alway off.

2- I just found some spark on the valve cover from #1 and #5 coil. I check the wire and I need to change almost all of them. They miss pieces I will change them asap.

Anymore help ?

question

iTrader: (2)

Sounds like a vac. leak to me - or sticking injectors. Had that problem among other and fixed both and poof running good now.

2000camaroSS2000

somthings wrong with tune probly

simpleboy77

iTrader: (10)

I remove all vacuum line and did not found nothing. I put them back and problem still there. The TPS is still unplug and run perfect ???

I call a tuner and will have a check on the tune in 2-3 weeks.

BlackScreaminMachine

iTrader: (17)

As long as things are running mechanically fine, I would def check tune, that is very common.

simpleboy77

iTrader: (10)

Update. The bolt on the intake was not tight down. I torque all of them to specs. It was way off. Do I need to reset the ecu ? The car still do the same thing and the SES is still there. Ben doing this for a long time I think. I remember the other owner did tell me the SES light was on/off for the last couple of mouth before he sold me the car. Car was maybe spray too (100 shot).

You think a need to remove the intake and change gasket ?