I did a tune up, new spark plugs, plug wires, distributor cap and rotor, went to start and it would not fire up, but would turn over. Checked and re-checked my work, re-installed all old stuff except plugs. Checked coil for defects reference haynes manual. measured resistance of the plug wires and the old bosch wire had a resistance ten times lower than the new carquest ones. ex; coil wire to the distibutor cap 8 inches in lenght, bosch 500 ohms car quest 4500 ohms and the same ratio for the rest of the wires longer wires higher resistamce. Did I blow something THis problem has never happened in seven years. I'm stumpped???
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Re: truck turns over but won't start 87 gmc 4x4
Well, if it was running prior to your replacing the plugs, then somewhere you went amiss. Check the firing order. If when you crank the engine over and it pops and backfires then you have a few plug wires mixed up. Other than that the other item to check would be the rotor button in side the cap. Is it lined up correctly or broken? Good luck.
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check for spark at the plugs then check for fuel. if one of these are missing the car won`t start. common problem on some of these was the ignition module in the distributor and sometimes the pickup coil wires would break. another thing to check is the distributor cap and rotor for damage like a cracked cap or burnt through rotor. fuel pump were also common.
The rotor spins inside the distributor cap. At the end of the rotor is a curved metal piece. At each spark plug, inside the distributor cap are metal posts that are cut out. When rotor spins inside cap a spark jumps from the rotor end to the post, to the plug wire ,to the spark plug.The space between the rotor and post in the cap where the spark jumps, is the air gap.
See if you have spark on at least two plug wires. If you do, but it is weak, you may just need a good tune up (plugs, wires, distributor cap, and distributor rotor). If you don't have spark or it is only on one wire, take the distributor cap off and see if the distributor is turning while someone turns the key. If it doesn't spin, you need a distributor because the bottom gear is broken or stripped. If it does spin, then it could be the coil, ignition module, crank sensor, fuse or wiring to any of these parts. It will take a lot of wire testing and diagnostics to figure out which part it is if it isn't just a simple tune up or distributor.
Hope this helps. Good luck!
YOU did the tune up? Check that the wires are in the right position, that the connection to the plug and distributor cap are good. Did you replace rotor and distributor cap? Wires could be needed. That wire might be bad
A diagram may not be needed as its a reasonably easy fix to do on your own.the distributor ca p will only fit on properly one way because at the base of the cap locaters can only fit the distributor if they line up.When doing the spark plug leads do them one at a time and if nessecary write or mark leads as 1,2 etc .The rotor can only fit on one way but put a mark on the distributor to show where the rotor was pointing when you took it off and if it still points there when the new one is fitted.When changing distributor cap and leads they have to go to the correct place.Pays to mark the outside of distributor cap where the locating bits are On the new and old one.Fit the new cap and rotor then take a spark plug lead and fit to new cap 1 at a time.You can tell by lining up the marks on the outside of the distributor cap when you hold them one on top of the other.Good luck