96 Tahoe Will not Start

QuantumFusion · December 10, 2004

I have a 1996 2-door 5.7 Liter 4x4 Tahoe. It started to run really rough Monday. Borrowed a scanner form a friend. It pulled a P0131 (Heated Oxygen Sensor (HO2S) Low Voltage Bank 1 Sensor 1) and a P0300 (Engine Misfire Detected). Changed out the Heated Oxygen Sensors and the Cap and Router. Nothing, still ran bad, but ran. Unplugged the battery for about 45 minutes. Reconnected it, will not run at all. Changed plug wires, Ignition Coil, Ignition Module, and Pick up coil. Nothing. It is turning over but not firing. My brother said he thinks it is not getting spark now. I will have my dad check that for sure when he gets home from work this morning. It is now pulling P1351 (Ignition Control (IC) Circuit High) and a MAF Code but I do not remember which one. Any ways, left the battery unhooked all night. Hooked it back up this morning nothing. Erased the codes as well (which is why I do not have the MAF code). It seemed like it almost caught twice this morning and fired up but it did not. Any ideas?

Rookie · December 10, 2004

is it getting gas????

QuantumFusion · December 10, 2004

is it getting gas????

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Seems to be.

QuantumFusion · December 10, 2004

I hear the Fuel Pump whine atleast.

Rookie · December 10, 2004

Make sure a filter is not clogged. My only advise is start with the basics. When trying to start it hit the gas a few times then sniff the throttel body to see if it smells of gas. Then i would look in to spark, check your coil.

QuantumFusion · December 10, 2004

It is getting fuel. We checked the fuel pressure release valve. It had gas.

Called a dealer, they said it could be the Ignition Switch. No idea where that would be. I will look. Any one else have an idea?

99-2door · December 10, 2004

It is getting fuel. We checked the fuel pressure release valve. It had gas.
Called a dealer, they said it could be the Ignition Switch. No idea where that would be. I will look. Any one else have an idea?

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I'm with them on the ignition switch. It is mounted on the steering column . Take the covers off and it is below the key cylinder. Disconnect the electrical connector for the column and seperate the ignition switch plug from the turn signal and wiper plugs.

Pretty easy to change.

Had a 98 S-10 doing the same thing you are describing and this was the problem.

Peter_C · December 10, 2004

There is more too it then what is suggested above. Missfire codes do not happen because of a bad switch, at least not from what I have heard. A bad switch causes the rig not to start. Fuel pressure can be 10 lbs too low and it will not start and if running lean can throw a P0300 code, along with causing 02 codes, although not the one yours threw. You need to check for fuel pressure and volume, and spark.

QuantumFusion · December 11, 2004

Spark, check. Not sure on the pressure, we did change the fuel filter. ANy other ideas?

mcreyaufmiller · December 11, 2004

After trying to start, does the security light blink?

QuantumFusion · December 11, 2004

After trying to start, does the security light blink?

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No security on it. Or least I think not.

Would it even try t o turn over if it was a security thing?

99-2door · December 12, 2004

After trying to start, does the security light blink?

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96 doesn't have the PASSLOCK system. Trucks didn't get that until 98.

budhayes3 · December 12, 2004

Just having spark and fuel isn't enough, it has to be adequate spark and fuel. Check for spark with an HEI spark tester...it looks like a spark plug with a clip on the end. Remove a spark plug wire and insert the tool, then clip it to a good ground. If the spark jumps the gap, it is OK. Next, you need to find the fuel pressure spec (I'm sure someone here knows it), and intall a guage and check cranking pressure. Just because fuel is present doesn't mean that it's enough to support combustion.