Firing order for a 1990 350 v8 chevy put new plugs and cap and it wont start

It is possible that the wiring of the cap was lost during the replacement. Included are some diagrams for the 6 and 8 cylinder. Confirm the sequance with the truck documentaTION.

Hope this helps?

I've uploaded a diagram that gives you the firing order for the 96 Chevy Cheyenne. The best way to find out which is number one in the firing order is to following the spark plug on the engine block back to the distributor cap. Number 1 is on the right side, closest to the front of the engine. Best of luck!

I don't know your year--make--model? You should be able to remove dist cap, crank the engine, watch which way the rotor turns, then you know the direction of rotation. Most chevy rwd v8, firing order, 18436572. The driver side bank is odd numbered, 1357.
The passenger side bank is even numbered, 2468 from front to back. Put your number one piston on tdc of compression stroke. Then whichever spark plug tower the rotor is leading into, should be number one, then you follow the firing order around the cap.

firing order for 5.7 v8 is 1-8-4-3-6-5-7-2 mostly all of the chevy v8s are the same firing order. the rotor button in distributer turns clockwise, the cylinder numbers are 1-3-5-7 on drivers side, 2-4-6-8 is on passengers side. To get started get your distrutor cap[new one] look on the top you will see a #1that's where you begin you must know if if rotates clockwise or counter clockwise start in that direction then follow the firing order and cylinder line up. good-day!! if cap is not marked, just pull out #1 plug, put a straw or similar in plug hole on top of piston. turn engine over by crank in front of vehicle with a wrench, when the piston comes to the very top just before it starts going down. this is tdc. and rotor button should be pointing to #1 wire on dist, cap. follow from there. good-day !!

This method is good for the firing order on all chevy small block v8 engines from 265 cubic inches to 400 cubic inches. This would include 265, 283, 305, 327, 350, 400 cu. in. chevy small block v8 engines.

Let's cover some safety concerns first. If you try to troubleshoot a mixed up firing order with the engine running, you could be in for a serious shock,.. literally. You can do it, with certain precautions, but you really don't need to check the firing order with the engine running. You definitely don't want to try checking the firing order if you are wearing any kind of pacemaker or sensitive electromechanical prosthesis. The voltage coming out of the ignition coil is in the thousands. Common sense dictates that you wouldn't stick a knife in an electrical outlet, so you wouldn't want to take chances with being shocked by the electrical discharge from your classic chevy's ignition coil either. See the diagram:




The firing order, which should be cast into the intake manifold, for the chevy small block V8 is 1-8-4-3-6-5-7-2. The firing order is the numerical sequence in which the spark plugs are fired. The insertion position of each spark plug wire around the circumference of the distributor cap can be found according to a clock face. The insertion sequence determines the firing order. The firing order is followed clockwise around the distributor cap starting from the 6:30 position with the 6:30 position being the number one cylinder spark plug wire.

On classic chevy small block engines that use ignition breaker points instead of electronic ignitions, the number one cylinder is the one immediately clockwise of the small metal sash cover on the distributor cap. The firing order starts here. There is no sash cover on the distributor cap for GM HEI electronic ignitions, and the firing order is the same, but starting at the 5:30 position.
The firing order makes sense if you know how the cylinders are numbered. The number one cylinder is the front most on the drivers side and 2 being the front most on the passenger side. From front to back, the cylinders are odd numbered on the drivers side, and even numbered on the passenger side.

Additional details HERE.

Hope helps (remmeber rated this).

You didn't post your engine size so please use the appropriate diagram:




GM (Cadillac) 250 (4.1L) V8 .GM (Cadillac) 273 (4.5L) V8 .GM (Oldsmobile) 307 (5.0L) V8 .GM (Oldsmobile) 350 (5.7L) V8 w/EFI.Engine firing order: 1-8-4-3-6-5-7-2 .Distributor rotation: counterclockwise





GM (Buick) 252 (4.1L) V6 .Engine firing order: 1-6-5-4-3-2.Distributor rotation: clockwise





GM (Cadillac) 368, 425, 472, 500 V8.Engine firing order: 1-5-6-3-4-2-7-8.Distributor rotation: clockwise





GM (Cadillac) 429 V8.Engine firing order: 1-8-7-2-6-5-4-3.Distributor rotation: clockwise

Sounds like your timing is off when you placed the distributor back in or your spark plug wires are crossed. Start with the simple and check the spark plug wire firing order. 1-8-4-3-6-5-7-2 Cylinder numbers drivers side 1-3-5-7 radiator to firewall. Cylinder numbers passenger side 2-4-6-8 radiator to firewall. Distributor cap #1 is at 5 O'clock and rotates clock wise. Once that is establish to be good then make sure the cylinder 1 is at TDC with the distributor rotor at the #1 position. Good luck and hope it's a crossed firing order.

Hi,
I don't know your engine size, but the link below is a picture of the GM small block firing order with distributor.
The firing order, which should be cast into the intake manifold, for the chevy small block V8 is 1-8-4-3-6-5-7-2. The firing order is the numerical sequence in which the spark plugs are fired. The insertion position of each spark plug wire around the circumference of the distributor cap can be found according to a clock face. The insertion sequence determines the firing order. The firing order is followed clockwise around the distributor cap starting from the 6:30 position with the 6:30 position being the number one cylinder spark plug wire.

http://www.classiccarauto.com/impala/how_to/images/distributor.png

Hope this helps...

on the intake manifold you will see 8 numbers, this is your firing order
from the front of the car the left side numbers are 1,3,5,7 and the right side are 2,4,6,8. now ont the distributor cap there should be a number 1 at one of the plug towers. you start there with #1 plug wireand continue.
on a chevy the firing order is 18436572 and this is the order you put the wires on the cap. now the second problem i don't know right off hand which way the rotor turns on your engine. so remove the cap and crank the engine over and see which way the rotor turns, this is the order you put the wires back on the cap. hope this helps