Topic: No Fire STUMPED!

[yjeep93]

I was out wheeling last weekend. It was running great all day. I got out to go chat and left it running. it sat for about 15 mins. i went to back out of my spot it back fired then died. Now back home it will crank but will not fire.

What i know-
Fuel pump is running and there is fuel to the rail
Replaced the OEM coil with a msd blaster unit
Replaced the crank sensor
Replaced cap and rotor.
There is power to the coil.
Checked all fuses/relays

any help?


Thank you!

[Jeffy]

Check for codes?

[sharpxmen]

when you crank it do you have power to the injectors (green/orange wire)?
do the injectors open (does the PCM give ground to the injectors, you can check with a 12v light bulb like the one under the dash)?
do you have spark?
do you have 5v at the MAP sensor and is there output from the MAP sensor?
do you have power at the crank and cam sensors? what's the fuel pressure (might want to start with this one, you said there's fuel but didn't mention if you checked the pressure or not)?

check these and go from there.

[jagular7]

If you know you have fuel and spark, check to see if both are getting into the cylinders.

See if the rotor is rotating with the cap off.

Pull a plug and see if its gas smelling.

If both, can't remember if the distributor runs off the cam or the crank. If crank, see if the timing chain is working properly by taking the valve cover off. You should see the rocker move up/down.

If all checks out, bring engine to TDC on #1 and check the rotor for proper location for firing.

I had similar situation where the gear sprocket on end of distributor shaft wore out and timing was not able to keep the engine running. I was on my way to CampJeep in Wisconsin from Kansas. I broke down in a town in Iowa after driving 3.5 hrs filling up with gas. I had a teardrop camper in tow and my 2 kids with me. Was able to get it repaired and back on the road in less than 2 hrs but at a cost of $250 or so IIRC. Still running the newer distro today some 5 yrs later

[yjeep93]

Thank you all for the quick posts!

I can not check for code because i do not have a key anymore. If there is another way to check that would be great! all injectors are firing. My problem is that i have no spark. My next guess is Ignition module is bad. Is there an easy way to check this or would this even be worth checking? Thank you all again!

[dwtaylorpdx]

It just needs ignition power cycled, even if your using a toggle switch that should work...

Dave

[sharpxmen]

Thank you all for the quick posts!

I can not check for code because i do not have a key anymore. If there is another way to check that would be great! all injectors are firing. My problem is that i have no spark. My next guess is Ignition module is bad. Is there an easy way to check this or would this even be worth checking? Thank you all again!

there is no ignition module, it is controlled by the PCM (or it is integrated into the PCM to be more specific). the spark is generated based on the crank sensor signal, the injector sequence is given by the cam sensor (in your distributor). check to see if you have power to the crank sensor and signal out of it when you crank the engine. Whatcoil did you use? is it a direct replacement for the stock one? do you have an oem one handy you can test with? can you also check with a light if you get signal to the coil connector when you crank the engine (should pulsate as well) - if you do then the coil is the issue, if you don't check the crank part to make sure you have power and signal (let me know if you need the procedure on how to check the crank signal, i can copy/paste out of the FSM).

[yjeep93]

Thank you guys for the quick replies! i have a buddy coming over this weekend to give me  hand.

sharpxmen-
I have a replacement coil just its a MSD model
and yes i have tryed using the oem one.
I have power to the coil with when the power is on but i have not been able to check for power to it or anything els when it is cranking but that will be some of the things we will check for this weekend.

Thank you all again. i will let you know if we figure anything out.

[yjeep93]

GOT IT! I never checked to see if the distributor was spinning while cranking. Turns out the gear had got stripped not letting it spin. So after a bundle of new parts i have learned my lesson.  TEST BEFORE YOU BUY! oh well though. Now i have trail spares.  Thank you all again

[sharpxmen]

GOT IT! I never checked to see if the distributor was spinning while cranking. Turns out the gear had got stripped not letting it spin. So after a bundle of new parts i have learned my lesson.  TEST BEFORE YOU BUY! oh well though. Now i have trail spares.   Thank you all again

and the trophy goes to jagular7:

See if the rotor is rotating with the cap off.

but what is surprising is that you said your injectors were firing although if your distributor is not spinning they shouldn't (or they will just do a couple of impulses and then stop since there's no cam signal).

[yjeep93]

i just assumed that they were firing sense there was fuel to the rail i had never checked to see if there were firing. i have not had a helper/remote start to be able to turn it over until today. live and learn. 

[sharpxmen]

i just assumed that they were firing sense there was fuel to the rail i had never checked to see if there were firing. i have not had a helper/remote start to be able to turn it over until today. live and learn. 

alright, we forgive you

glad you figured it out.