Idle and stalling issues
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From: The beautiful Kingdom of Bahrain
Idle and stalling issues My car is a auto 98Z. When my car is cold and or sometimes warm if I start it the rpm's jump straight to 2000 rpm's and stay there. If I shut the car off and restart a couple of times it'll drop back down. In drive it idles at 1k. We have the idle set for 850. so my questions are what could be some of the causes of this and with my mods what should my idle be? I plan on spraying some carb cleaner to check for vacc leaks. Next Ill adjust the T/B some. Anything else?
02 Z28 SHORT BLOCK
FRESH REBUILT TRANSMISSION LESS THAN 5 MILES
HPT TUNERS TUNED PCM
ASP UNDER DRIVE PULLY
TRANSGO SHIFT KIT
DUAL GAGE POD WITH WATER TEMP AND A/F GAUGE
TSP PRC STAGE 2.5 HEADS, SS 2.04 INTAKE VALVES, 1.575 EXH VALVES, PRC DUAL VALVE SPRING KIT, AND TSP HARDENED PUSHRODS.
ROLLMASTER SINGLE NON ADJ TIMING CHAIN
NEW GM COMPLETE GASKETS
TSP LS6 PORTED OIL PUMP
TSP 233/239/113 CAM
PACESETTER CERAMIC COATED HEADERS
TRUE DUAL X PIPE EXHAUST W/ spirals
FORD 30LBS INJECTORS
YANK 4000 STALL TORQUE CONVERTER
TR55 SPARK PLUGS
160 DEGREE THERMOSTAT
3.73 REAR GEARS
K & N AIR FILTER
02 Z28 SHORT BLOCK
FRESH REBUILT TRANSMISSION LESS THAN 5 MILES
HPT TUNERS TUNED PCM
ASP UNDER DRIVE PULLY
TRANSGO SHIFT KIT
DUAL GAGE POD WITH WATER TEMP AND A/F GAUGE
TSP PRC STAGE 2.5 HEADS, SS 2.04 INTAKE VALVES, 1.575 EXH VALVES, PRC DUAL VALVE SPRING KIT, AND TSP HARDENED PUSHRODS.
ROLLMASTER SINGLE NON ADJ TIMING CHAIN
NEW GM COMPLETE GASKETS
TSP LS6 PORTED OIL PUMP
TSP 233/239/113 CAM
PACESETTER CERAMIC COATED HEADERS
TRUE DUAL X PIPE EXHAUST W/ spirals
FORD 30LBS INJECTORS
YANK 4000 STALL TORQUE CONVERTER
TR55 SPARK PLUGS
160 DEGREE THERMOSTAT
3.73 REAR GEARS
K & N AIR FILTER
do you have a SES light on? a few thing off hand i can think of is
1 crossed vac. hoses or hoses not put on right
2 MAF (if you took the screen off and ported the ends)
3 I took one of those universal breathers from Advance auto parts and ran a catch can and put one of those breathers after the catch can before the PVC hose goes into the TB... the outcome was rough idle and stalling. so if you've done that... that's your problem.
4. sometimes bad auto trannys cause higher idle, can't explaine it b/c not my specialty, but i have a 89 rs 305 tbi and 700r4 tranny, it had given me rought idle beofer my overdrive went out, then 3rd went out on me... they took it apart and the friction plates for 1 and 2 gear were shot to sh*t. i would have never known that was my high idle problem if i wasn't told so.
1 crossed vac. hoses or hoses not put on right
2 MAF (if you took the screen off and ported the ends)
3 I took one of those universal breathers from Advance auto parts and ran a catch can and put one of those breathers after the catch can before the PVC hose goes into the TB... the outcome was rough idle and stalling. so if you've done that... that's your problem.
4. sometimes bad auto trannys cause higher idle, can't explaine it b/c not my specialty, but i have a 89 rs 305 tbi and 700r4 tranny, it had given me rought idle beofer my overdrive went out, then 3rd went out on me... they took it apart and the friction plates for 1 and 2 gear were shot to sh*t. i would have never known that was my high idle problem if i wasn't told so.
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From: The beautiful Kingdom of Bahrain
Originally Posted by FU_I_AM_UltraZ
do you have a SES light on? a few thing off hand i can think of is
1 crossed vac. hoses or hoses not put on right
2 MAF (if you took the screen off and ported the ends)
3 I took one of those universal breathers from Advance auto parts and ran a catch can and put one of those breathers after the catch can before the PVC hose goes into the TB... the outcome was rough idle and stalling. so if you've done that... that's your problem.
4. sometimes bad auto trannys cause higher idle, can't explaine it b/c not my specialty, but i have a 89 rs 305 tbi and 700r4 tranny, it had given me rought idle beofer my overdrive went out, then 3rd went out on me... they took it apart and the friction plates for 1 and 2 gear were shot to sh*t. i would have never known that was my high idle problem if i wasn't told so.
1 crossed vac. hoses or hoses not put on right
2 MAF (if you took the screen off and ported the ends)
3 I took one of those universal breathers from Advance auto parts and ran a catch can and put one of those breathers after the catch can before the PVC hose goes into the TB... the outcome was rough idle and stalling. so if you've done that... that's your problem.
4. sometimes bad auto trannys cause higher idle, can't explaine it b/c not my specialty, but i have a 89 rs 305 tbi and 700r4 tranny, it had given me rought idle beofer my overdrive went out, then 3rd went out on me... they took it apart and the friction plates for 1 and 2 gear were shot to sh*t. i would have never known that was my high idle problem if i wasn't told so.
Originally Posted by senicalj4579
I had a similar problem happen to me and it turned out to be from the map sensor.
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From: The beautiful Kingdom of Bahrain
As of right now we did some tuning and closed the throttle body some and it seems to be helping. The car has gone from stalling out all the time to mabey one time in 10 attemps to reverse. Sometimes when I blip the throttle or go from open to close to fast it surges really low but isnt shutting off anymore. We cleaned the throttle body very well with carb cleaner so were going to wait a couple of days to see how it works out.
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From: Minnesota
Same thing I have the same thing happening but I have M6. I have tried all the other tricks I found searching but nothing has helped. I still have a hanging idle when I push in the clutch. Settles a bit once the car has fully stopped.
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From: The beautiful Kingdom of Bahrain
Originally Posted by Thumdaddy
I have the same thing happening but I have M6. I have tried all the other tricks I found searching but nothing has helped. I still have a hanging idle when I push in the clutch. Settles a bit once the car has fully stopped.
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Originally Posted by 98Camarod
How did you figure out it was the map sensor? I am having the same problem as you, it shoots straight to 2k for a second and then idles at 1k and surges. Thats going to suck to change on mine, hopefully I can change it out without taking the mani off if thats the problem.