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I'm just trying to figure out which 3126 I have. I see all
Thanks. I'm just trying to figure out which 3126 I have. I see all these 3126E, B, etc. mine doesn't match any of their picks or diagrams. S# ***** … read more
Cat Man
Cat Man
Cat Engine Expert
Vocational, Technical or Trade Scho
10,186 satisfied customers
Have a question about a series 60 Detroit in a 1991
Have a question about a series 60 Detroit in a 1991 Peterbilt … read more
Mike Mcmillan
Mike Mcmillan
Triage Tech/Shop Foreman
Associates
352 satisfied customers
Got a 2001 gmc topkick with 3126 in it. Was running fine.
Got a 2001 gmc topkick with 3126 in it. Was running fine. Went to start long cranking. Had already run into bad inj actuation sensor couple weeks back. Fixed that. I unplugged the sensor again to test… read more
Cat Man
Cat Man
Cat Engine Expert
Vocational, Technical or Trade Scho
10,186 satisfied customers
I have a 2007 9400i with a c15 and a no data link message on
I have a 2007 9400i with a c15 and a no data link message on the dash … read more
Andy
Andy
truck /coach technician
Vocational, Technical or Trade School
207 satisfied customers
I have a 3126 cat I'm trying to start but I need wiring
I have a 3126 cat I'm trying to start but I need wiring diagram for ecm connector on truck side … read more
Cat Man
Cat Man
Cat Engine Expert
Vocational, Technical or Trade Scho
10,186 satisfied customers
My cat 3126 won't start. It's a 2001 gmc t series truck with
It's a 2001 gmc t series truck with a cat 3126 engine … read more
Cat Man
Cat Man
Cat Engine Expert
Vocational, Technical or Trade Scho
10,186 satisfied customers
2004 isuzu npr diesel. I have problem with the automatic
2004 isuzu npr diesel. I have problem with the automatic transmission : AW450-43LE. ELECTRONICALLY TCM, SOLENOID, SENSORS IS NEW. IN D POSITION S1 SOLENOID ON, S2 OFF THE TRUCK DON'T HAVE POWER, PRESS… read more
Daniel Wilson
Daniel Wilson
Auto Mechanics 1&2/diesel mech
4,431 satisfied customers
1998 gmc c8500 cat 3126. Engine will start and then die
1998 gmc c8500 cat 3126. Engine will start and then die after a short period. The low coolant light is coming on before it dies. Coolant level is good. Have tried disconnecting the sensor and no chang… read more
spankyjr1
spankyjr1
Retired
Vocational, Technical or Trade Scho
420 satisfied customers
I have 2005 gmc 7500 with a C7 3126 while cranking I have no
I have 2005 gmc 7500 with a C7 3126 while cranking I have no rpm but if I spray it with starting fluid it will start. I can keep it running as long as I keep the pedal going once I try to let it idle … read more
Cat Man
Cat Man
Cat Engine Expert
Vocational, Technical or Trade Scho
10,186 satisfied customers
Cat 3176 no start has fuel pressure of 80 labs but no voltage
Hi cat 3176 no start has fuel pressure of 80 labs but no voltage at injectors 9 pin round connector at head… read more
Cat Man
Cat Man
Cat Engine Expert
Vocational, Technical or Trade Scho
10,186 satisfied customers
HAVING TROUBLE STARTING OUR CAT ENGINE. TRUCK IS A 98 GMC
HAVING TROUBLE STARTING OUR CAT ENGINE. TRUCK IS A 98 GMC 6500. ENGINE IS A 3126, ALLASON TRANS. ENGINE RAN GREAT A FEW DAYS AGO. NOW IT WONT START. STARTS WITH STARTING FLUID, BUT WONT CONTINUE TO RU… read more
Cat Man
Cat Man
Cat Engine Expert
Vocational, Technical or Trade Scho
10,186 satisfied customers
Cat man got 98 3126 in a gmc t7500 truck that starts and
hey cat man got 98 3126 in a gmc t7500 truck that starts and runs fine but goes into limp mode and only revs to 1700 unless u shut off and restart, it only has a obd2 connector and doesnt want to comu… read more
Cat Man
Cat Man
Cat Engine Expert
Vocational, Technical or Trade Scho
10,186 satisfied customers
98 3126 in a c6500 gmc starts and runs good until I drive it,
98 3126 in a c6500 gmc starts and runs good until I drive it, It runs strong for a minute, then acts like it is out of fuel. I let off for a second or 2 and give it fuel and again runs strong for a fe… read more
Cat Man
Cat Man
Cat Engine Expert
Vocational, Technical or Trade Scho
10,186 satisfied customers
Cat Man, I'am working on a CAT 3126 in a 2003 Freightliner
HI Cat Man, I'am working on a CAT 3126 in a 2003 Freightliner truck. The engine serial #is HEP18235.It was hard to start it (turned over fine just wouldn't fire), after firing and stalling twice it fi… read more
Cat Man
Cat Man
Cat Engine Expert
Vocational, Technical or Trade Scho
10,186 satisfied customers
I swapped out a c7 serial # ***** and installed a 3126 serial
I swapped out a c7 serial # ***** and installed a 3126 serial # ***** I put all the c7 sensors on the 3126 (plugged right in). the truck turns over but wont fire/start. any suggestions?… read more
Cat Man
Cat Man
Cat Engine Expert
Vocational, Technical or Trade Scho
10,186 satisfied customers
Mod#3126 Ser# ***** Engine turn over but does not start.
Mod#3126 Ser# ***** Engine turn over but does not start. I have the large red wire connected to battery positive and the large black wire connected to battery negative and two small wires black to neg… read more
Cat Man
Cat Man
Cat Engine Expert
Vocational, Technical or Trade Scho
10,186 satisfied customers
GMC c6500: I have a 2000 gmc c6500 and no start has a 3126
I have a 2000 gmc c6500 and no start has a 3126 cat. I also loose power to the pink wire at the brake light interface module can you tell me where it is located… read more
Andy
Andy
truck /coach technician
Vocational, Technical or Trade School
207 satisfied customers
WE HAVE A 2004 GMC C7500 WITH A CAT 3126 THE TRUCK QUIT RUNNING
WE HAVE A 2004 GMC C7500 WITH A CAT 3126 THE TRUCK QUIT RUNNING AND WONT START. OUR MECHANIC REPLACED THE LIFT PUMP STILL NO START WE COULD UNPLUG THE SENSOR ON THE TOP OF THE HIGH PRESSURE PUMP AND I… read more
Cat Man
Cat Man
Cat Engine Expert
Vocational, Technical or Trade Scho
10,186 satisfied customers
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Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

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