diego94

Iv got a 91 4L aw4

Its cranking but won't go..this is completely out of the blue has always been reliable..always starts right up but its just cranking right now...I checked all fuses and they r good..starters cranking just fine, I checked all the connections and they are good..I can hear the fuel pump working.. Last year it got new cps, tps, map, coolant temp sensor, oil pressure sensor...also has new fuel pressure regulator and a new last year fuel ballast resistor.. My nss died a little wile ago but haven't had time to fix it so I just grounded it and its been fine since, it still cranks and without it grounded it wouldn't so that has to be good to..

Just a little stumped and when I search for no start problems its stuff that iv already replaced that comes up.
Any help appreciated thx

HEAP of JEEP

Have you checked for spark or fuel at the rail? Figure out what's missing, spark, fuel, or compression, and then you'll have a better idea where to focus your diagnostics to. Fuel and spark are easy enough to check without any special tools. Pull a plug wire and corresponding plug, ground it to the block, and have someone crank the engine while you observe the plug. You want a strong snappy blue spark. For fuel, you can just depress the schrader valve and see if there's any fuel pressure. You might eventually need a fuel pressure tester, but for now, see if the fuel rail is getting any fuel at all.

DFlintstone

Agreed with Heap, check for spark. Here's an HO CPS check we can do. (an untested test)

Check this out. It's for 97, but this or something like might be interesting. I think you have three wires that do the same thing, but the position's and colors may well be different. Btw I probably would not disconnect all the injectors. I don't see hand crnking it a little "rincing the cylinders" For sure the coil though, you don't want it to fire!
>> http://troubleshootmyvehicle.com/jee...crank-sensor-2

diego94

My roommates at work so I don't have anyone help me at this exact moment but I can go and do those tests

diego94

Where is the shrader valve ?

diego94

Nvm found it

diego94

Got it thx guys

Crazy 8s

What was the issue and what fixed it? Useful for those who may have similar experiences to yours...

DFlintstone

X2 Crazy. OP you found the shrader valve or you found the problem?

diego94

About a month ago snow wheeling I overheated it and blew the rad cap...coolant everywhere and there was a small electrical fire that is irrelavent to this...but when I was working on it yesterday I had fuel pressure but only a weak spark...going through everything on the ignition system I found a lot of coolant under my distributor cap...amazed it only gave me problems now cause there was a puddle in there...long story short all my tools r in storage so I borrowed a friends hair dryer and stuck it on the cap and distributor till all moisture evaporated and walla runs without a problem again