Running like Sh!t

[Trizz5253]

So when i start my car in the morning it wont run right. It idles at about 600 rmp and if you hit the gas it misses and sputters. As soon as the temp gauge moves to 1/4 of the gauge the RPMs jump up and it runs fine. I changed the coolant temp sensor and still runs the same way. what else should i try. Thanks!

 

[jbl_5star]

sounds like Idle Air Control Valve, which is under the throttle body. Depends if you have one plated of not.
But that ICV controls idle, if its going bad it will either surge or idle funny.
also check plugs and wires

also check you vacuum lines.

 

[Trizz5253]

Well i just went out for my first ride and noticed something. the kid i bought it from had installed a volts gauge and it seems like when i start the car the volts sits just under 12 and the car runs like sh!t. Then the guage will jump to 13.5 or 14 and it runs fine? What would be causing this.

 

[jbl_5star]

faulty battery, bad ground

bad connection

 

[Trizz5253]

Its a good battery and i put on the terminials they were clean and tight. If it wax a bad ground wouldn't it not start at all or something wouldnt work right? Cause it does the same thing every time you start the car. If it is a bad ground where should i look. Thanks for the help.

 

[jbl_5star]

with the gauge jumpin up might just mean ## atlernator is charging the battery.. check your ICV

 

[Trizz5253]

Is there a tech article in the ICV? i couldn't find one and have no idea how to check that. Thanks

 

[jbl_5star]

ISC also.

How to Check an Idle Air Control Valve | eHow.com here is a site how to check the ICV
and here is a video explaining IAC (correct not ISC its IAC)

turn on your AC full blast, and turn your wheels hard left or right and check for idle increase, if there is no increase it might be the IAC

4G63 crap idle / stall
2LiterRiceEater
08-10-2008, 04:35 PM
Well I kept having idle problems with my N/T 4G63. It would run normally, but when coming to a stop the revs would drop to 300-400 for a quick second, then climb back up. The whole car would vibrate.

So today, I had to leave. Start the car, drive down the driveway, and it stalls. Start it back up, stalls again. I did this a few times, and decided to move her around. So I drove up the street, and when coming to the stop sign, I pressed in the clutch, took it out of gear, and it stalled again. I circled around the block a few times and it got better.

My question is, what could it be? I need to get it fixed, because she sure as hell isn't getting better.

Please help me.
oilyboy
08-10-2008, 06:17 PM
Do a search on idle surge ,even if your idle is not surging this will still point you in the right direction.
2LiterRiceEater
08-11-2008, 09:23 PM
Do a search on idle surge ,even if your idle is not surging this will still point you in the right direction.

It does surge. It also decreases by 50-100 RPM if I apply the brakes (moving or not) and also decreases if I turn the wheel all the way (power steering)

Sorry I could not have searched, we had a big thunderstorm that wiped out our modem, so I was just on my buddy's computer and quickly posted this. I did not have time to search.
93_GSX
08-11-2008, 09:45 PM
Its and idle control valve or something similar. Someone with a better memory will post something soon....
DSMX1
08-14-2008, 05:34 AM
I had the same problem, i replaced my MAFS and the problem cleared up, also look into ECU capacitors.

go to vfaq.com for more info on the ECU
trinistylz2002
08-20-2008, 06:42 PM
Well I'm trying to diagnose my idle surging issue. I've been doing some research on Vfaq and wanted to know if the idle surge problem have any direct relation to why I have been running out of power steering fluid so quickly.
JimG4652
08-30-2008, 02:21 PM
Does it only surge with the A/C on? I agree with 93 GSX with the IAC motor. Before you replace the IAC though, I would check your throttle body for build-up. I had the same problem, cleaned my nasty throttle body, and my car is idling fine now. Someone correct me if I'm wrong, but you shouldn't use a wire brush to clean the inside of the throttle body so you don't scrape off the teflon coating inside the TB. I removed the TB and TB sensors, replaced the $4 TB gasket, and cleaned it with gas and a rag.
2LiterRiceEater
08-30-2008, 06:13 PM
Na the it only stalled that one time, and I never have the A/C on. Since then it never gave me any problems. I have no idea why it stalled on me just that one time.

By the way, it's a 4G63 non-turbo.
GSXPimp
08-30-2008, 06:25 PM
man my 420a is having the same problem...i have been trying to find out what is going on also. I gave it new plugs and checked for a vacume leak but it still does it only when it wants. If i hold the RPMs to 2k it will drop after half a second later to about 1400 RPMs then when i let my foot of the pedal it will just die. Any help for us?
Johnrossf
09-02-2008, 06:26 PM
You should check the following:

1. Resistance on the ISC motor/idle valve motor should be around 29 to 30 in ohms. Replace isc if bad.

2. Check to see if tp sensor is not bad.

3. Clean the throttle body with throttle body cleaner and replace gasket. make sure the circular plate attached by two screws are does not have play or loose.

4. Check the caps on the ecu underneath your center dash. ECU can be accessed by removing the screws of the left and right center console covers. Replace burnt caps, or check for burnt components. Solution: Buy one at a local junk yard. Goes around $30. The one I got is working well.

5. EGR sometimes causes hot air to go to intake, which causes the lower rpms during stops.

6. Fuel cuts can cause your problem as well. Replaced your fuel filter or have you checked your fuel pump too?

7. Stepping on the gas, or using power steering uses cause battery power usage. Thus the observable power rpm dip. I installed a power recharging unit to keep the volts steady.

I can't think off anything else that you can check to solve your idle problem. What do you guys think? Just a basic check list.
2LiterRiceEater
09-13-2008, 02:04 PM
Wow, it did the same thing again to me today. Overcast weather, humid, I took it out of the garage to go to work, and by the end of the street, it stalled when I took it out of gear and it began to idle.

The whole way there and back idle sucked. It dipped down to 400-500ish for a second, then climbed back up to normal everytime the revs went down.

 

[my dreamt dsm]

My car is running the same way. When it's cold in the morning and I let it idle to normal 750rpm and I start to move the car, it would feel like it's running very lean or something. If I give it about 30% throttle the car would feel like it's sputtering or misfiring. I've read somewhere that the car is in closed loop or something until it opens up again then the car would run like normal.
This may be your problem OP.

 

[Trizz5253]

Just another newbie question everyone talks about their car stalling but mine never stalls always catches itself. It just has no power, spits and sputters, and not power but no stalling. Really thanks for all your help i really do appreciate it.

 

[jbl_5star]

try all that, see if it helps, im almost sure it will solve your problems<

 

[1991_talon]

Maybe your running an open thermostat check what your temp gauge reads when you start it and how long it takes to get to around dead center.

 

[Trizz5253]

It tales awhile to warm up but the only thing that would make sense is when i drive its at like 1/4 gauge all the time. The car def runs colder than any other car i have ever driven. do you think an open thermostate would make the car un like that as well. And just to point out about the voltage guage again its at 12 and the car runs like sh!t but once it jump to 13.5 or 14 the car runs great anything to do with that? Also i am checking and cleaning the IAC today and ill let you know what i find. Thanks for all the help.

So i just pulled the ICV out and it waqs a little bit dirty to i cleaned it up and nothing seems to change. I forgot to mention t=yesterday the batt light and brake light are both always on but not on full really dim and when i hit the brakes i noticed the rpms would drop out. I dont get why it is doing this but not the ICV in this case. any other ideas? Thanks, RY

So i just pulled the ICV out and it waqs a little bit dirty to i cleaned it up and nothing seems to change. I forgot to mention t=yesterday the batt light and brake light are both always on but not on full really dim and when i hit the brakes i noticed the rpms would drop out. I dont get why it is doing this but not the ICV in this case. any other ideas? Thanks, RY