Because the timing is advanced.
loosten distributer bolt, point the timin light at the timing grid on the harmonic balancer and turn the distributer to either advance or retard the timing.
buy a timing light. clip it to the #1 plug wire. loosen the bolt on the distibutor. Unplug the timing advance. start the engine Point it to the harmonic balancer and turn the distributer until the timing mark on the timing cover lines up with the mark on the harmonic balancer. Tighten the distibutor bolt. plug in the timing advance.
to find timing marks, look to see if there is a :L: shaped tag bolted to front of engine ,just above the harmonic balance on front of crankshaft. this is the equivalent to top dead centre on when lined up with marks on harmonic balance(pulley wheel). thetdc mark should line up with this then advance or retard timing on smaller marks or with timing light
I had the same prob. with my 98 Tahoe it has a 350 but if your motor is computerized and is vortec im sure its the same. the computer times it for you.
bright yellow or green
For mechanical time take of your distributor cap put your #1 piston all the way up on the compression stroke(TDC). Point your rotor button at the #1 piston . Disconnect the vac advance. reconnect everything use a timing light to fine tune it the light hooks to the #1 plug and the Battery. the timing marks should be on the crank pulley/ harmonic balance Just aim and turn your distributor until you hit what the book says. Good luck, and then reconnect your advance.
Normally by turning the distributor, in conjunction with a strobe timing light
The timing marks should be on the balancer and the timing cover. If they are not there, someone removed the window marks.The timing marks should be on the balancer and the timing cover. If they are not there, someone removed the window marks.
Well to begin with, it all depends on where you live. For example, if you live in Colorado the timing should be set to 10 degrees before top dead center (BTDC). First, there is an in-line spout connection. It looks like a jumper plug. Unplug that connector. Then get a timing light, one with an advance dial, and set the dial at 10 degrees, and "shoot" it at the harmonic balancer. On the 2.9L V6 the timing marks are on the harmonic balancer. There is an arrow that sits over the harmonic balancer on the passenger sider of the engine. Locate it and "shoot" your timing light at it. If the timing light is set at 10 degrees, then the number on the harmonic balancer should look like this TIC. That means you're timing is right on the money. If it doesn't then loosen up the distributor hold down clamp and turn the distributor until it goes to TIC. Hope this helps. Clay Colorado
YES! Any time you adjust the timing you should disconnect the vacuum advance.
Petrol engineYou really need a strobe timing light to set the timingThe timing marks are visable through an appature in the bellhousingTo advance the timing you need to rotate the distributor bodyclockwise.
there will be a timing mark on the harmonic balancer. and a timing tab on the timing chain cover. point your timing light at the timing tab and you should see the timing mark on balancer. if not timing is way out.markstang.