How much is the RPM showing in the datatlogger while cranking?
SOURCE: I have a 1991 Jeep Cherokee 4.0. It ran fine
spark is triggered by the crank sensor and the cam sensor inside the distributor. but the actual signal to the coil comes from the computer. If I remember correctly the hot side of the coil runs to the back of the alternator. I am sending along a complete wiring diagram for your vehicle but I suggest you get a haynes or chiltons manual for test procedures. Don't follow their wiring diagrams or you will get side tracked to death trying to figure them out (inaccurate is a mild word)
http://www.scribd.com/doc/18999822/Jeep-Wiring-2
Since I can't do the testing from here, I;m trying to give you the best possible means and chance to figure this out. Any questions just ask!!
SOURCE: got a good one. my 91 coupe original 5.0 car.
the fuel injectors are fired by computer producing a ground signal to them. so its unlikely they are fireing at once.possible power supplie problem but that would cause no injector pulse.beings how the engine was just replaced i would go over every wire and all grounds to make sure they are not shorted or pinched under a manifold or something.if you pull the plugs and they are black then you are getting to much gas. in wich case i would check to see if the fuel pressure regulator diaphram may be ruptured.if you take off the vacuum hose to it and look for moisture from gasoline. or leave hose off and try to start it if gas squirts out that regulator is bad and needs replacement
SOURCE: i have a 92 ranger
it will run on a either spray without a spark but not not petrol ,now without my greasy hands under the bonnet i would ask you as you obviously can do a bit yourself to check for a spark before you go any further ,pull the centre lead out of the distributor cap and then crank engine and see if you get a spark ,the nice fat juicy blue one ,if a weak yellow spark then a least you know what your up against either a weak coil or a crank sensor or what i would go for and thats the ignition module first.Now if it was the mass iair flow then i would expect it to run but not rev up ,if it was the flow meter valve on the throttle body then i would have expected it to run with petrol sprayed into intake like you have done but to only run on either leads me to suspect the strength of the spark .Anyway dinner is served and dearly beloved is shouting *'¡?? so i had better go ,best of british with it
SOURCE: 93 jeep cherokee country 4.0
Hello crichardson.
OK, here are all the things to check for.
Spark on all ignition wires,
compression test all cylinders,
ignition timing,
good fuel(not old or contaminated),
injectors firing (have voltage pulse).
Is the crankcase flooded with fuel? Smell the oil. Drain it if it's full of gasoline and put in fresh oil.
I have seen spark plugs that have been flooded that won't fire, even if they look clean.
If the distributor cap and rotor are old...toss them, they are cheap to buy new. Old ones can crossfire internally and rotors can short to ground.
Putting your fuel pedal to the floor while cranking shuts off the fuel injectors. This is called "clear flood mode"
I am telling you this for two reasons.
One that it may be handy to get it started and two to tell you that a shorted throttle position sensor can cause a no start.
Are there any codes stored in the computer? If there is, start there. It may lead you to your no start issue.
There you are, a few ideas, I hope that one of these helps get you running again.
Thank you for using FixYa.
KL
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SOURCE: 85 Jeep Cherokee will crank
Check for spark at any of the sparkplugs.If there is no spark at the plug then replace the distributor ignition pickup coil.
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