91orangexj

92 jeep cherokee laredo won't start. replaced the cps, replaced the ignition coil, replaced the fuel filter, and replaced the battery. any other ideas on what to try or what to replace?

widefieldcherokee

spark plugs, wires, cap and rotor, fuel pump the list could go on an on u need to do some tests to see wat ur missin u need air compression fuel and spark find which one ur missin and then tell us

tjwalker

Right. You need to start doing some fundamental testing to see what starting component you are missing.

Always start with SPARK. Remove a plug, keep it attached to the plug wire, place the plug electrode near a good engine ground, have a buddy crank the engine while you watch. You are looking for a strong, blue, snapping spark. Yellow/orange/white spark indicates a weak spark, which may not be strong enough to start the engine.

Spark okay? Then perform a quick and dirty test. Spray a small amount of starting fluid or a splash of fuel into the intake. If the engine starts and runs momentarily, then you have confirmed a FUEL DELIVERY problem.

Post back your results. When you know the results here, the suspect list gets a whole lot shorter. And every no-start is a process of elimination.

freegdr

three basics fuel ,spark,injector pulse.

Potatowalker

So your XJ could go wheelin on the moon! Or maybe even make it to Hawaii unassisted?!? I want this MOD!

sorry, you forgot air and I couldn't resist

99KeeSport

Fuel, Spark, Air. Very true. Do you know how to test for each?

If you need help testing for each, post the question(s) if you're not sure how to.

Remember, a spark may not be a 'good enough spark'.

Injectors may pulse but until you visually see fuel spraying out the injector(s) you can't be sure fuel is getting to the chamber. (one or two bad injectors should still let the truck start and run like crap though).

Also, for the fuel, spark and air trilogy to work TIMING is VERY important. The fuel must be present when the sparkplug sparks. Timing chain jump/break? Distributor shaft gear shreaded?

Did this problem 'suddenly' occur? Or did it get harder and harder to start as days went by? If suddenly, it's probably a certain compenent. If over time, something or multiple things were degreading and finally when tango uniform.

Follow the events that have to happen to make the engine 'ignite'. Check each step/part along the way. This will keep you from throwing parts at an issue.

NOTE: If the engine cranks, it's not the nuetral safety switch. If you have spark, it's not the Crank Position sensor.

Northwoods Snowman

This may sound basic, but to cover the bases, is it even turning over? You just said it won't start, but didn't say it was turning over.

91orangexj

there are sparks when we test them. we just replaced the fuel pump, we are getting good pressure. what else could it be?

tjwalker

Just because you have good fuel pressure doesn't mean that fuel is getting TO the fuel injectors.

Try this quick and dirty test. Spray a small amount of starting fluid or a small splash of gas into the intake. If it starts and runs momentarily using this technique, you have now confirmed a FUEL DELIVERY problem. This takes all of 10 minutes and is good info.

red_dog007

does the engine continue to crank over but not start, or does it not even crank?

could be a bad starter or alternator.

91orangexj

mind giving me (a rookie) of where the intake is? and i don't know what crank over means.

Northwoods Snowman

Crank over means the engine turns over, or spins when it tries to start.

91orangexj

sprayed starting fluid in the intake, and still won't start...whats next?