motor wants to stall when at a stop?
03-25-2011, 11:21 AM
#101
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Re: motor wants to stall when at a stop?
Nothing? As in cranks but no start? Or no crank? Did you transfer your PROM to the new ECM? Try diconnecting the battery to reset.
03-25-2011, 10:24 PM
#102
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Car: 89 GTA/93 S13/91 Si
Engine: 5.7 350 TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: motor wants to stall when at a stop?
like, it fires then immediately dies.
i did transfer the PROM and when i did it i dropped the ECM fuse.
think ima just have the shop diagnose it and ill fix it (as long as i can)
03-26-2011, 10:54 AM
#103
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Re: motor wants to stall when at a stop?
Does your have car VATS? Is it possible you blew the security fuse? GM also used 2 different pulsewidths of fuel enable signal over different years. It's vital that your VATS module or bypass module and ECM match in this regard.
03-26-2011, 11:24 PM
#104
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Car: 89 GTA/93 S13/91 Si
Engine: 5.7 350 TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: motor wants to stall when at a stop?
yeah it has vats
hmm...is it just in the fuse panel? i can check it 2marro.
hmm...is it just in the fuse panel? i can check it 2marro.
03-26-2011, 11:44 PM
#105
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Re: motor wants to stall when at a stop?
The security fuse is in the fuse panel, along with the ECM fuse. If the ECM and VATS module are mismatched you'll get a code.
03-27-2011, 01:34 AM
#106
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Car: 1988 GTA
Engine: 5.7 TPI w/ Bosch III's
Transmission: T56
Axle/Gears: 3.27 Borg Warner 9 bolt
Re: motor wants to stall when at a stop?
Maybe I missed it in a post but, did you ever get a chance to check the fuel pressure?
03-27-2011, 04:22 PM
#107
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Car: 89 GTA/93 S13/91 Si
Engine: 5.7 350 TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: motor wants to stall when at a stop?
gonna check the fuel pressure today actually 
what do you mean if they're mismatched? like differant amp fuses??
what do you mean if they're mismatched? like differant amp fuses??
03-28-2011, 02:31 AM
#108
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Re: motor wants to stall when at a stop?
No. I mean that the VATS(passkey) module produces a low rate fuel enable signal(30MHZ IIRC) and the new ECM takes a high rate signal(50MHZ IIRC). It's a stretch if you got the same p/n.
Just noticed something you said in post #102. You say you "dropped" the ECM fuse. Do you mean you blew it or just dropped it?
Just noticed something you said in post #102. You say you "dropped" the ECM fuse. Do you mean you blew it or just dropped it?
03-28-2011, 12:07 PM
#109
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Car: 89 GTA/93 S13/91 Si
Engine: 5.7 350 TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: motor wants to stall when at a stop?
no i mean i took it out and looked at it..
03-28-2011, 12:50 PM
#110
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Car: 90 Formula 350 ws6
Engine: l98 5.7 tpi. minor mods.
Transmission: auto 700r4 b&m shift kit
Axle/Gears: posi 3.73 richmond
Re: motor wants to stall when at a stop?
ok stupid question...this is my first third gen and tpi..so im having the same prob as all discussed above..where is the ecm located at?..and i hope this is the problem!..cuz i broke the carnial rule and just started throwin parts at it...
03-28-2011, 07:57 PM
#111
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Car: 89 GTA/93 S13/91 Si
Engine: 5.7 350 TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: motor wants to stall when at a stop?
its under the kick panel above the passanger side
03-28-2011, 10:07 PM
#113
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Car: 1988 GTA
Engine: 5.7 TPI w/ Bosch III's
Transmission: T56
Axle/Gears: 3.27 Borg Warner 9 bolt
Re: motor wants to stall when at a stop?
I hope that is a newly purchased GTA being dropped off...sharp looking car.
Always sad to see a nice GTA on a flatbed. Good luck.
Always sad to see a nice GTA on a flatbed. Good luck.
03-29-2011, 10:03 AM
#114
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Car: 89 GTA/93 S13/91 Si
Engine: 5.7 350 TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: motor wants to stall when at a stop?
thanks yeah..it got to the shop around 12noon yesterday so hopefully ill know whats wrong with it today
yeah..it got to the shop around 12noon yesterday so hopefully ill know whats wrong with it today
03-29-2011, 11:18 AM
#115
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Re: motor wants to stall when at a stop?
If it ends up being something simple, we'll all have a good laugh and shake our heads that we didn't think of it. If it ends up being complicated, we'll feel vindicated. Either way life will go on and you'll get your car back on the road. I wish we were closer geographically. I would have loved to have your car into my shop.
03-29-2011, 11:44 AM
#116
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Car: 90 Formula 350 ws6
Engine: l98 5.7 tpi. minor mods.
Transmission: auto 700r4 b&m shift kit
Axle/Gears: posi 3.73 richmond
Re: motor wants to stall when at a stop?
yea im def interested to find out! mines driving me crazy!
03-29-2011, 12:58 PM
#117
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Car: 91 Z28
Transmission: 700R4
Re: motor wants to stall when at a stop?
My 91 may have a similar issue. Mine only starts stalling after its driven a little bit and warms up. Its in the shop now for a rearend issue so I haven't had the opportunity to check anything yet. Ill be very interested to see what the problem with yours turns out to be.
03-29-2011, 01:19 PM
#118
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Car: 89 GTA/93 S13/91 Si
Engine: 5.7 350 TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: motor wants to stall when at a stop?
If it ends up being something simple, we'll all have a good laugh and shake our heads that we didn't think of it. If it ends up being complicated, we'll feel vindicated. Either way life will go on and you'll get your car back on the road. I wish we were closer geographically. I would have loved to have your car into my shop.
i know its something simple that im just over looking...
i should be getting the diagnostic back today so ill let everyone know what it ended up being
03-29-2011, 07:05 PM
#119
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Car: 90 Formula 350 ws6
Engine: l98 5.7 tpi. minor mods.
Transmission: auto 700r4 b&m shift kit
Axle/Gears: posi 3.73 richmond
Re: motor wants to stall when at a stop?
cool man thanks alot!!..cant wait to find out what it was..hope it doesnt set u back too much!
03-29-2011, 07:27 PM
#120
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Car: 1991 z28
Engine: 305 tpi
Transmission: 700r Automatic
Re: motor wants to stall when at a stop?
i also have a 91 i feel bad with you kinda bein the guinnea pig but funds are low for me to take the car in the shop 
so i hopw youre diognoses and remedy will be that same as mine
so i hopw youre diognoses and remedy will be that same as mine
03-29-2011, 10:11 PM
#121
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Car: 89 GTA/93 S13/91 Si
Engine: 5.7 350 TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: motor wants to stall when at a stop?
03-30-2011, 01:29 PM
#122
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Car: 89 GTA/93 S13/91 Si
Engine: 5.7 350 TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: motor wants to stall when at a stop?
turned out to be a huge vacuum leak in some of the old cracked rubber lines and the iac needed a good cleaning
charged me $120
also had to tighten up my torque converter
it was rattling and knocking..was also a persistant problem but never bothered to look into it..
charged me $120
also had to tighten up my torque converter
it was rattling and knocking..was also a persistant problem but never bothered to look into it..
03-30-2011, 03:19 PM
#123
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Car: 91 Z28
Transmission: 700R4
Re: motor wants to stall when at a stop? (was a vacuum leak and dirty iac)
Well I'm glad to hear that it was nothing major or super expensive. When I get mine back from the shop I plan on doing a major tune up on it and had already planned on cleaning the IAC and checking all the vacuum lines. Hopefully I'l take care of the problem while doin all that.
03-30-2011, 08:43 PM
#124
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Re: motor wants to stall when at a stop? (was a vacuum leak and dirty iac)
LOL. Did I forget to say always start with the basics. Can you see me shaking my head? I'll nave a good laugh when I get past feeling like a dumb@$$. Happy to hear it was some thing simple. Makes it much less painful. Happy Motoring!!!
03-30-2011, 10:40 PM
#125
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Car: 89 GTA/93 S13/91 Si
Engine: 5.7 350 TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: motor wants to stall when at a stop? (was a vacuum leak and dirty iac)
lol..got it home and the fan thing started happening it again
put the new ecm in and it seems to be running good..will report back if persists
put the new ecm in and it seems to be running good..will report back if persists
03-31-2011, 10:42 AM
#126
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Car: 90 Formula 350 ws6
Engine: l98 5.7 tpi. minor mods.
Transmission: auto 700r4 b&m shift kit
Axle/Gears: posi 3.73 richmond
Re: motor wants to stall when at a stop? (was a vacuum leak and dirty iac)
well turned out to be a bunch of old cracked vaccum lines!!..i cleaned the iac and voila!!! runs like new!!..guess we all learned a valuble lesson here...never overlook the small things!..btw i feel like a dumba$$ as well...lol..thanks for the help guys!
03-31-2011, 10:59 AM
#127
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Car: 89 GTA/93 S13/91 Si
Engine: 5.7 350 TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: motor wants to stall when at a stop? (was a vacuum leak and dirty iac)
no problem ^^ haha
yeah, the car stumbled this morning when i picked my freind up but it seemed fine after so we'll see after school..
will report back
yeah, the car stumbled this morning when i picked my freind up but it seemed fine after so we'll see after school..
will report back
04-01-2011, 10:24 AM
#128
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Car: 90 Formula 350 ws6
Engine: l98 5.7 tpi. minor mods.
Transmission: auto 700r4 b&m shift kit
Axle/Gears: posi 3.73 richmond
Re: motor wants to stall when at a stop? (was a vacuum leak and dirty iac)
ok so here we go..i guess i jumped the gun yesterday..i cleaned the iac..checked and rechecked all vacuum lines..ran good till this morning..its doing it even worse now!..i have to put it in neutral to keep it running!!!..ive changed plugs,wires,cap.rotor,coil.tps,ran i bottle of lucas oil fuel system cleaner through it..im at a loss...any suggestions??
04-01-2011, 12:59 PM
#129
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Car: 89 GTA/93 S13/91 Si
Engine: 5.7 350 TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: motor wants to stall when at a stop? (was a vacuum leak and dirty iac)
start a new thread
it started doing the weird fan thing where i can keep it in gear at a stop and the ses light stays on....
so i limped it back to the shop...lol
we'll see what that is now....
it started doing the weird fan thing where i can keep it in gear at a stop and the ses light stays on....
so i limped it back to the shop...lol
we'll see what that is now....
04-01-2011, 01:05 PM
#130
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Re: motor wants to stall when at a stop? (was a vacuum leak and dirty iac)
Im curious to know what code(s) it's thowing now.
04-01-2011, 03:30 PM
#131
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Car: 89 GTA/93 S13/91 Si
Engine: 5.7 350 TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: motor wants to stall when at a stop? (was a vacuum leak and dirty iac)
shop said it didnt store any codes but they bench tested the MAF and it spikes up to 99gallons and jumps all over...
soooo..new MAF -__- lol
soooo..new MAF -__- lol
04-01-2011, 04:44 PM
#132
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Car: 90 Formula 350 ws6
Engine: l98 5.7 tpi. minor mods.
Transmission: auto 700r4 b&m shift kit
Axle/Gears: posi 3.73 richmond
Re: motor wants to stall when at a stop? (was a vacuum leak and dirty iac)
aw man..that takes me out...no maf on mine.
04-01-2011, 05:05 PM
#133
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Car: 89 GTA/93 S13/91 Si
Engine: 5.7 350 TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: motor wants to stall when at a stop? (was a vacuum leak and dirty iac)
yeah..just gonna get a remanufactured autozone one..only $120
04-01-2011, 09:31 PM
#134
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Car: 89 GTA/93 S13/91 Si
Engine: 5.7 350 TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: motor wants to stall when at a stop? (was a vacuum leak and dirty iac)
okay so idk if its the MAF causing the problem...its weird..
the fan comes on when i turn the ignition on and after i start it, its still on and the ses light is still on and it wants to die when its put in drive. but when its in park or neutral, it idles really high.
idk wtf is up with this beast -__-
the fan comes on when i turn the ignition on and after i start it, its still on and the ses light is still on and it wants to die when its put in drive. but when its in park or neutral, it idles really high.
idk wtf is up with this beast -__-
04-01-2011, 11:28 PM
#135
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Car: 1991 z28
Engine: 305 tpi
Transmission: 700r Automatic
Re: motor wants to stall when at a stop? (was a vacuum leak and dirty iac)
have you rpelaced yuor cts yet...mine was doing similar things so after replacing a million sensors and reading codes i took it to my mechanic...he replaced the cts sensor and fan switch...havent gotten the car back yet but ill be picking it up next thursday ..mechanic says its good to go ill let ya know after i get it and drive it a while
04-02-2011, 01:14 AM
#136
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Re: motor wants to stall when at a stop? (was a vacuum leak and dirty iac)
From the bench test results, it sounds like a bad MAF. However, if the tech doesn't double check his test, he could cause the spike by poor test lead contact. The CTS could cause the same drivability issue and would explain your fan running on. CTS is easy to check with a DVOM. It should read 3,400 ohms at 70 degrees and 180 ohms at 220 degrees.
04-02-2011, 02:50 AM
#137
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Car: 89 GTA/93 S13/91 Si
Engine: 5.7 350 TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: motor wants to stall when at a stop? (was a vacuum leak and dirty iac)
ill have him check the cts..i didnt even think about that!
ill check the fan switch as well...
ill check the fan switch as well...
04-02-2011, 09:55 AM
#138
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Car: 90 Formula 350 ws6
Engine: l98 5.7 tpi. minor mods.
Transmission: auto 700r4 b&m shift kit
Axle/Gears: posi 3.73 richmond
Re: motor wants to stall when at a stop? (was a vacuum leak and dirty iac)
man hope you get it fixed..i know how frustrating it is!!..im gona try new iac and let u guys know how it goes..
04-04-2011, 09:58 AM
#139
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Car: 89 GTA/93 S13/91 Si
Engine: 5.7 350 TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: motor wants to stall when at a stop? (was a vacuum leak and dirty iac)
gonna change the maf and cts today hopefully...where is the cts again? and how do i go about removing it?
04-04-2011, 01:37 PM
#140
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Re: motor wants to stall when at a stop? (was a vacuum leak and dirty iac)
The CTS is at the very front of the intake manifold below and beside the thermostat housing. One yellow and one black wire to it. The easiest way to change it is when the engine is cold. Loosen it and have the new one ready to go in, remove the old one and quickly insert the new one. When changing the MAF, be sure to verify that all wiring and connections are good.
04-04-2011, 03:06 PM
#141
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Car: 89 GTA/93 S13/91 Si
Engine: 5.7 350 TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: motor wants to stall when at a stop? (was a vacuum leak and dirty iac)
alright cool..will do that today hopefully
04-04-2011, 06:19 PM
#142
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Car: 89 GTA/93 S13/91 Si
Engine: 5.7 350 TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: motor wants to stall when at a stop? (was a vacuum leak and dirty iac)
swapped the CTS...ran good. drove it. went back out to it like an hour later and its doing the fan thing again...
now tho, when i put it in gear..it wont stall. its just really hesitant and has a loss of power.
IDEAS?????????????
now tho, when i put it in gear..it wont stall. its just really hesitant and has a loss of power.
IDEAS?????????????
04-04-2011, 11:41 PM
#143
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Re: motor wants to stall when at a stop? (was a vacuum leak and dirty iac)
Have you determined if the MAF is reading correctly? Which fan comes on, left or right?
04-05-2011, 01:27 PM
#144
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Car: 89 GTA/93 S13/91 Si
Engine: 5.7 350 TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: motor wants to stall when at a stop? (was a vacuum leak and dirty iac)
im not sure on the readings but the brown oval thing in the center of the maf has a few cracks in it.kinda looks like heat stress cracks.? its the Bosch one..
its the drivers side fan...all the fan wiring looks good so its something telling it to turn on..would the maf do this?? my dad said it might but hes not sure..
its the drivers side fan...all the fan wiring looks good so its something telling it to turn on..would the maf do this?? my dad said it might but hes not sure..
04-05-2011, 08:36 PM
#146
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Re: motor wants to stall when at a stop?
Driver's side is the primary fan. It is controlled by the ECM according to information from the CTS. It will also run under certain fault conditions and in diagnostic mode. It doesn't run with AC. That's the secondary/condenser fan. A scan tool would show if it's being commanded on by the ECM or if there is a fault in the relay or wiring. Sounds like the MAF is in bad shape. Bosch was OEM.
04-05-2011, 10:29 PM
#147
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Car: 89 GTA/93 S13/91 Si
Engine: 5.7 350 TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: motor wants to stall when at a stop?
i changed out the MAF today..still doing it..
i bought a CTS but couldn't get to it cuz my headers air tubes -__-
the cts is on the passenger side right?
i bought a CTS but couldn't get to it cuz my headers air tubes -__-
the cts is on the passenger side right?
04-06-2011, 12:19 AM
#148
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Re: motor wants to stall when at a stop?
No. CTS is at the front of the manifold. Black and yellow wires. The accessory brackets may make it hard to get to but you should still be able to do it.
04-06-2011, 12:20 AM
#149
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Re: motor wants to stall when at a stop?
Bummer about the MAF. This is why I always test using a scanner so I can verify changes in data while I test circuits.
04-06-2011, 02:57 PM
#150
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Car: 89 GTA/93 S13/91 Si
Engine: 5.7 350 TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: motor wants to stall when at a stop?
i changed the cts already..(the first time it was said)