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Calling all cars...

James

Well-known member
Joined
Apr 7, 2012
Messages
1,322
Location
Port richey Florida
Yes, this is about idle problems, but it's past the basics now...

Well I've reached the end of my line on stopping the galant from dying at idle when it reaches temp.

I have no vac/boost leaks that I can see or hear. (using soapy water ect)

I rebuilt the TB.

3in exhaust no cat magnaflow muffler

Boost gauge, running boost off wastegate pressure (10lbs)

I've essentially replaced everything on the intake side, from the Jpipe up to the intake Mani gasket.

ISC/TPS are In spec, no cels

The car runs fine at cool temps, I assume the ISC is doing its job correctly. When the car reaches temp, or aprox 8 miles worth of driving, the idle will begin to falter when I push in the clutch, say to put it in N for a stoplight.

If I I turn the car off, say to go into a store, when I come out she runs fine, till the temp is back up and the same issue repeats itself. Here are some videos to depict what's happening.

I'm I'm need of obscure help, because the basic vac leak/FIAV/ISC answers aren't going to cut it anymore.

First video here is showing the fresh cool motor idle, with a few second of exhaust.

click

Second video is me at a stoplight/sign with my lame issue, I blip the gas up to 1500 for a second, and the end I'm trying to hold it around 8-9

click

Third video is me coasting down a side street in neutral, showing the same. The. A small third gear pull /ubbthreads/images/graemlins/wink.gif

click

I swear this has to be something temperature related. Maybe computer related? Could it be the ECU? I don't have another one to swap out and see.

She was playing nice when I took the videos and didn't die at all, just faltered. Usually she will bounce down once or twice then die on the third try. It's quite embarrassing really.]
 

James

Well-known member
Joined
Apr 7, 2012
Messages
1,322
Location
Port richey Florida
Yes
 

James

Well-known member
Joined
Apr 7, 2012
Messages
1,322
Location
Port richey Florida
I don't have anything to log with :/ I bought a palm logger from a member here but it didn't work when I plugged it in.

I'm also at a Loss as to how to fix that. But that's another day.

I don't have a different ECU, and the only local DSMer uses an AEM brain.

If someone has a ECU they would like to send me to test that would be great. Obviously I'll play shipping both ways.
 

DynastyLCD

Well-known member
Joined
May 12, 2006
Messages
761
Location
Harwinton, CT
ive got an idea for you. let the car get fully up to temp, turn on all the lights and highbeams, fan motor for your heat/AC, radio, etc. with it warmed up, adjust that BISS screw til you can idle at 850 - 1000.

i've seen alot of people set it improperly, where they will set it to idle low (750 - 850) with no lights or any electrical load on. but then as soon as you hit the lights and the radio, etc, wants to die cause the idle drops off too low.
 

James

Well-known member
Joined
Apr 7, 2012
Messages
1,322
Location
Port richey Florida
It's not the biss I know that, the idle is properly set. I'll check the coolant sensor, I assume I can find the info on vfaq.
 

LIV4PSI

Well-known member
Joined
Nov 24, 2011
Messages
1,774
Location
O-H-I-O
I would at least check the caps on your ECU. If it hasn't been rebuilt it, I'm sure it needs to be soon.
 

James

Well-known member
Joined
Apr 7, 2012
Messages
1,322
Location
Port richey Florida
The ECU is clean. I posted a thread about my ECU about a month ago. Found out its a clean 92 eagle talon 5 speed non EPROM ECU.

Apparently my multi isn't in my car, so I'll have to wait till tomorrow after work to check the coolant sensor.
 
Last edited:

ktmrider

Well-known member
Joined
Sep 10, 2007
Messages
3,128
Location
Tempe, AZ
James I realize you bought a logger however you NEED to get some type of real-time measurement device. You'll continue to go round-round on the site til then.

Did you ever bypass the FIAV ( just FIAV and not the ISC )? Can't see that in any of your posts. Also the suggestion about another ECU is sound too, so many ECU ISC drivers get damaged by even a slightly bad ISC. Logger will also tell you what your ISC duty cycle is at, another great way to tell the health of your ECU.
 

James

Well-known member
Joined
Apr 7, 2012
Messages
1,322
Location
Port richey Florida
Trust me I want to be logging, I didn't want to throw away $80 to get a logging setup that didn't work.

But the palm won't connect with my car. I think it has something to do with the car being a galant GSX, maybe the wiring in the diagnostics port is slightly different.

The TB is blocked off, FIAV only, ISC still functional.

If someone has a extra ECU they don't need then send it to me to test with! I'll pay shipping
Both ways. But sadly port richey Florida is the home of non turbo old people cars. I don't have 10 Dsm buddies I can call up to swap ecus with.
 

James

Well-known member
Joined
Apr 7, 2012
Messages
1,322
Location
Port richey Florida
I'll be checking the coolant today after work. And I'm picking up a timing light to check my base timing, since I never did it when I bought the car.
 

James

Well-known member
Joined
Apr 7, 2012
Messages
1,322
Location
Port richey Florida
The voltages from the coolant plug ad sensor are so far off that I think I'm doing it wrong.

I'm not seeing anything on the sensor side with ohms, and I'm seeing 50v +\- on the plug side.
 
Last edited:

James

Well-known member
Joined
Apr 7, 2012
Messages
1,322
Location
Port richey Florida
eh the voltmeter was on millivolts or something i guess when i saw the 50. i couldnt get any reading on the correct setting. my stepdad lost the set of grounding wires i had made up so i cant ground out the timing plug to check my base timing.

all in all im done for the time being. its a thousand degrees outand im tired of something so simple like a bad idle getting the better of me when ive been around this platform for so long. ill just learn how to work the brake and the gas at the same time when im coming to a stop to keep the car from dying.
 

James

Well-known member
Joined
Apr 7, 2012
Messages
1,322
Location
Port richey Florida
Got the coolant temp sensor replaced today (thanks Jnr). But it didn't fix anything, the sensor was bad though so I'm sure I'll probably get some better gas mileage!

Only thing left is ECU I think...
 

doelcow

Active member
Joined
Sep 14, 2010
Messages
35
Location
Norfolk, VA
Make sure you don't have any air pockets in your coolant. I know it sounds crazy but... it can mess with your idle.
 

James

Well-known member
Joined
Apr 7, 2012
Messages
1,322
Location
Port richey Florida
I'm pretty sure I got all the air out, though again I don't think that ls something that would only cause this to happen when hot.

I'm driving down to ft Myers for the weekend and I'll be meeting a DSM buddy down there. He has a extra ECU and has link so we will not only be trying a good ECU, but getting some logging done also! (assuming it connects with the car, unlike mine).
 
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