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I have a2002 c7500 3126 engine code 42 is active truck will
I have a2002 c7500 3126 engine code 42 is active truck will crank but won't start … read more
Nich1019
Nich1019
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I've got an 01 fl60 3126 cat showing 32 and 56 using the
I've got an 01 fl60 3126 cat showing 32 and 56 using the cruise control button but can not find a manual to see what the codes are … read more
Nich1019
Nich1019
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I have a 99 freightliner fl60 with a cat 3126 with huei
I have a 99 freightliner fl60 with a cat 3126 with huei injection system and I accidentally knocked a 10amp fuse out of the fuse panel in the cab on the passenger side while the truck was running.. on… read more
Daniel Wilson
Daniel Wilson
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1999 freightliner fl60 with cat 3126. Will not start. Wait
1999 freightliner fl60 with cat 3126. Will not start. Wait to start light not coming on and scanner will not communicate with ecm. Unplugged wiring harness going to sensors to rule out a shorted senso… read more
Cat Man
Cat Man
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Cant find starter relay on 2000 c8500 with the cat motor, no
cant find starter relay on 2000 c8500 with the cat motor , no medium duty info , all car and light duty. … read more
JoshD429
JoshD429
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I'm wanting to swap out my 8yl 3126 out of 2000 c7500 I want
I'm wanting to swap out my 8yl 3126 out of 2000 c7500 I want to put in ckm 2002 3126 for more power Don't know if I use old ecm or new on because for gauges ect … read more
Nich1019
Nich1019
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1999 GMC C8500, Cat 3126, Allison MT 653. I installed a
1999 GMC C8500, Cat 3126, Allison MT 653. I installed a reman Allison. It now gives random check engine lights and derates the engine. No codes stored, but a drive test says loss of vehicle speed sign… read more
Daniel Wilson
Daniel Wilson
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I have a 99 c6500 with a 3126. fast idle not working.
i have a 99 c6500 with a 3126. fast idle not working. looking for specs on what I should be looking for when testing the two wires at the switch. … read more
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Would like to start diagnosing a problem with my 3126 using
Would like to start diagnosing a problem with my 3126 using cat man … read more
Cat Man
Cat Man
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99 cat 3126 no comucation with scanner. Ser# 8yl21261 99 gmc
99 cat 3126 no comucation with scanner JA: What is the complete model and serial number of your machine? Customer: ser# ***** 99 gmc 7500 JA: Are you fixing this yourself? What have you tried so far? … read more
Daniel Wilson
Daniel Wilson
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2003 f650 3126 cat died wont start check engine light does
2003 f650 3126 cat died wont start check engine light does not come on now communication with cat et, have power and ground to ecm and ignition hot on pin 70, replaced ecm with reman from cat still ca… read more
Cat Man
Cat Man
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Cat 3126 is not staying running it'll start and run for 30
Cat 3126 is not staying running it'll start and run for 30 to 60 sec then will shut off then not run at all I have tried to run a scan on the computer but it comes back no ecm but after 4 of 5 hours i… read more
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Started and stalled a while then quit anyway if the engine
started and stalled a while then quit anyway if the engine service light and wts light comes on it will run for a moment if not it will not can not get scanner to connect can not get cruise codes to p… read more
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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
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We have a c8500 with a cat 3126 motor. Engine will turn over
We have a c8500 with a cat 3126 motor. Engine will turn over but will not start. Changed the oil pressure sensor. Did not help … read more
Daniel Wilson
Daniel Wilson
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I have a cat 3126 crank no start. using a snap on scanner
i have a cat 3126 crank no start. using a snap on scanner but I don't know how reliable it is when I'm reading inputs. another shop replace iap sensor. this morning it had 0 psi cranking, 180-220 rpm,… read more
Cat Man
Cat Man
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Vocational, Technical or Trade Scho
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1999 GMC C7500 3126 Cat. Occasional hard start. "No ECM
1999 GMC C7500 3126 Cat. Occasional hard start. "No ECM detected" when hooking up scanner.… read more
Cat Man
Cat Man
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2000 GMC topkick with a 3126 cat engine. Shut off while running,
2000 GMC topkick with a 3126 cat engine. Shut off while running, will not restart. Checked voltage to ecm. 12 volts to pins 52 an 53 .I have 1200 psi. pressure in high pressure manifold while cranking… read more
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Cat Man
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Daniel Wilson

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cumminsdr

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Chris (aka-Moose)

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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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