idle prioblem HELP

[GSXdsm97]

OK well first let me start by saying i have posted this problem before but now it is worse. I dont have my lap top becasue it got sent to service so i cant get any logs up. here is my problem,

my car will idle rought at 1500 go up to 2000 than drop to 1500 than go back to 2k.. it does this all the time. than if I am lucky it will idle right at 700. or it will go the down to like 200 and than stahl out.. I dont know what to check. I replaced my O2 so that is brand new I just put it in today any help would be great thanks
ps what should my AFP be set at

 

[liquidz28]

I assume you have tested your ISC and made sure your biss is not loose?
if you have done so you should say that when you post so we can better assist.
my idle did that also, was the ISC had a vacc leak around itself. never stalled out but would seek idle at all temps. check that !

 

[GSXdsm97]

ISC sorry this is a new one for me what does that mean

 

[lostsenerio]

try the tps it may cause that

 

[liquidz28]

idle speed control module,
its plugged in right under yout throttle body

 

[GSXdsm97]

ok i did some research and found out what that was, how do i get to it, Where is it located

 

[GSXdsm97]

man you guys are fast
what would i do to adjus the TPS

 

[GSXdsm97]

ok i am out workin on my car now. how do i check the isc.. i have my battery out that weas the only way i could get the clip off

 

[Jeff99GS]

Did you have any check engine lights on? If so you need to check them. Usually if the ISC is bad it will turn your Check engine light on.

You need to do a Boost Leak test....and scan your ECU for codes

 

[GSXdsm97]

i havent done a boost leak test. but my gauge is saying that i am holding vac. and when i hold boost it holds at 16psi as for codes yea i am throwing a injector circuit malfunction code.....

 

[Jeff99GS]

HMMM...almost sounds like you may have a Leak around your Injector seals...My suggestion would be DO A BOOST LEAK TEST ASAP and listen around your injectors.

are your injectors stock?

Is your fuel pump stock?

Do you have and adjustable Fuel pressure regulator?

 

[GSXdsm97]

no 650cc

no walbero 255

yes full throtle FPR

 

[Jeff99GS]

no 650cc

no walbero 255

yes full throtle FPR

You need to put a full list of your engine mods in your profile so we can help you easier....you should also check your fuel pressure with a gauge off the service port on your fuel rail

How long ago were the injectors installed?

 

[GSXdsm97]

sorry this stuff is basdicly about 2 months old. i have aguage on my FPR what should it read at. also i might be missing 2 or 3 spacers between my injectors could that make this happen

 

[Jeff99GS]

Dissconnect the Vacuum line off your AFPR while the car is idling...your Fuel Pressure should be 43.5 with the vacuum line dissconected....if its not 43.5 then lower it to 43.5 and re connect your vacuum line.


If you dont have the spacers in between the bolts and you tightend the bolts down then it probably pulled the injectors crooked. You might be leaking air aroung the injector O-rings.

I would definately try to find the spacers or at least get some washers or something.

Make sure the Injectors are fully seated in properly....sometimes it helps to grab them and wiggle them in a rotating fashion clockwise and counter clockwise.

what is holding the fuel rail in if you dont have the spacers in with the bolts?

 

[GSXdsm97]

i checked the AFP its at 43. as far as the spacers its the one from the fuel rail that connects the injectors...

 

[Jeff99GS]

i checked the AFP its at 43. as far as the spacers its the one from the fuel rail that connects the injectors...

yeah You Definately need those...Thats your problem for sure i'll bet.

 

[liquidz28]

simple way to test the ISC is pull it from the motor, have an assistant start the car. you will see the penis protrude/retract from the ISC motor, not far, just "average" as the ladies say , you can do this while holding it, you will feel clicks. also if it is leaking around the seal wich mine was and resulted in the exact same symptoms. check the ISC first because it is the easiest with what you have to work with, but yes, invest in a small 5 gallon tank and build your leak tester, dont make the mistake of not regulating the air comming from your tank tho . hopefully this helps.

 

[fatherbubble]

I say idle air control thats exactly what mine did when it went bad. As for cost there only around 60 -80 bucks an in stock at autozone.

 

[liquidz28]

bah, i allways remember crap after i post, the CEL will be lit if there is a malfunction
(P0505), but will not be lit if theres a leak.

 

[GSXdsm97]

Yea i mean i just unpluged the battery so ill check it in a little bit, as for codes before that, the only one I have is an injector circuit malfunction on cylinder two. (all the clips were checked on the injectors all reading the same thing). so it seems to be idling fine now. but who knows. tomorrow is a new day.

 

[Jeff99GS]

Yea i mean i just unpluged the battery so ill check it in a little bit, as for codes before that, the only one I have is an injector circuit malfunction on cylinder two. (all the clips were checked on the injectors all reading the same thing). so it seems to be idling fine now. but who knows. tomorrow is a new day.

Its NOT that I think the injectors are BAD...They Might just not be seated in properly. Or you May have forgotten to plug one in all the way...I would definately Pay attention to what the Check engine light is telling you first!
If its idling OK now as you said, then CLEAR out your engine light...and wait a few days to see if it RE-APPEARS

I would do a boost leak test still

Just Pressurize your system to about 18 psi with an air compressor and listen for leaks...spray some soapy water all over the Throttle body, Intake Manifold, Injector seats, ISC, TPS, BISS, AFPR, and all Vacuum lines.

let us know how it turns out

 

[GSXdsm97]

I had it at a shop and they did a pressure test and that checked out also they did check for leaks around my VC but, i guess they didnt check for boost leak. Ill try and get it done in the next day or two and post back up.. o and what is BISS, AND TIPS

 

[GSXdsm97]

well today i get in the car and it idles fine than about 20 mins later i push the clutch in to stop at a light and the car stalhs on me. anytime i push the clutch in the car wants to stalh. it doesnt hold at 750.

 

[RedTalon95]

well today i get in the car and it idles fine than about 20 mins later i push the clutch in to stop at a light and the car stalhs on me. anytime i push the clutch in the car wants to stalh. it doesnt hold at 750.

I had this problem as well, I had multiple vacuum leaks. I'd do a boost leak test first and foremost. Also, as was mentioned before, you could be leaking at your injectors.