1999 GMC Sonoma engine cranks but does not turn over

1999 GMC SONOMA
114,000 MILES • 6 CYL • 2WD • AUTOMATIC
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DTRAIN
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I tried to start my Sonoma and nothing happened. I pulled the battery, had it checked (was bad) and replaced it. Same condition - turn the key, nothing happened.

Pulled the starter and found the wire connecting the starter motor to the solenoid was broken. Replaced the starter. The engine cranks over but does not start.

Replaced the distributor cap/rotor and the fuel filter. No change. The ignition coil was replaced about a year ago. I tested it with an ohm meter and it checked out.

The fuel pump will engage to prime the system when the key is turned. I have not checked the fuel pressure at the schrader valve at the intake yet. I did try starting fluid but it did not work.

Thanks in advance for your help.
Jun 25, 2009 at 5:58 AM
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RACEFAN966
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Ok have you checked to see if it has spark? If not do that first and lets determine where we need to go from that point. So disconnect a spark plug wire from a plug and put a phillips screw driver in the end and place it near metal ie:valve cover and crank it over and see if there is spark. Let me know what you find and we will go from there. I also need to know if the 8th digit of the vin is an X or W.
Jun 25, 2009 at 9:23 AM
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DTRAIN
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it ends in X

tried the screwdriver - no spark or any indication of one
Jun 25, 2009 at 12:13 PM
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DTRAIN
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changed the ignition coil since it failed one of the three tests - no change

one 30amp fuse was blown in the main compartment under the hood - changed it as well and no change.
Jun 25, 2009 at 4:51 PM
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RACEFAN966
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Ok lets do a couple of simple checks first just to be sure of what is what before going to crazy ok. I need you to check the ICM 1 fuse in the under hood fuse box it is a 15 amp fuse. Then I need you to do a power check on the control module and see if it getting power at the pink wire with the key on engine off. Then check the white wire at the ignition module. I also need to know if you have power to the pink wire at the coil. If this checks out then we will check the cam and crank sensors. Let me know what you find. Here is a pic of the control module to help you find it.


https://www.2carpros.com/forum/automotive_pictures/249564_51097_1.jpg

Jun 26, 2009 at 9:41 AM
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DTRAIN
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control module:

pink wire - 10.07

white wire - 0

coil:

pink wire - 9.34


I did replace the cam pos sensor - no change
Jun 26, 2009 at 10:47 AM
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DTRAIN
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i checked every fuse again under the hood and in the panel inside the driver's door - all good
Jun 26, 2009 at 11:04 AM
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RACEFAN966
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With that it seems that you have a bad ignition module. There are no more tests to do at this point.
Jun 27, 2009 at 9:25 AM
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DTRAIN
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so you feel that it is the ignition control module instead of the crankshaft sensor?
Jun 27, 2009 at 9:36 AM
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DTRAIN
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i changed the ignition control module but it did not help
Jun 27, 2009 at 2:13 PM
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DTRAIN
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i do have a spark at the plug now
Jun 27, 2009 at 4:09 PM
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DTRAIN
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tried starting fluid in the throttle body - with and without the maf sensor in place - no start
Jun 27, 2009 at 4:55 PM
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RACEFAN966
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First sorry it took so long to get back to you but I went camping with my family we needed time away from it all. So with that said what color is the spark at the plug? Do you hear the fuel pump run at all? Have you a way of checking the fuel pressure? Please quit using starting fluid as it is very hard on an engine use throttle body cleaner instead. I really need to know what the fuel pressure is it takes 65 psi to open the injector when starting and 55 or so when running so this is important to know.
Jul 1, 2009 at 9:26 AM
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DTRAIN
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checked fuel pressure at the schrader valve on the rail this morning

ignition on and pump priming - 62

ignition on and pump no longer priming - 56

attempting to start the engine - 62 to 64

The spark was blue in color
Jul 1, 2009 at 9:57 AM
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RACEFAN966
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OK do you have a way of checking the injectors for resistance? If so check that and let me know what you find at each injector. The fuel pressure is a little low but I don't think it is low enough to keep it from starting. It should be 60-66 psi no lower if it is lower then the fuel pump or fuel pressure regulator are the suspect.
Jul 2, 2009 at 9:24 AM