My B1500 van quit on me last night,it is a 3.9 Magnum V6, port EFI.It started to miisfire and pop through the air cleaner and stalled.I got it to run again,had to feather the throttle,luckily I was less than a mile from home and made it.
Well no start today,I checked fuel pressure it seems ok @ 40 psi and flow volume is good.It has spark but will not fire,even attempted starting fluid. I checed the timing mark vs distributor rotor alignment and it is good.I thought timing chain possibly but the van only has 40k on it. Spark at the plug is ok,maybe weak.Spark at coil term is very good.Is it possible for a crank sensor,or even the cam sensor/dist pickup to fail and still allow a spark?
This is OBD I,Im going to see if my neighboring shop has a scanner that will check cranking rpm if it is possible.When my trucks crank sensor failed it was no spark at all.Just wondering if anyone has had a similar experience on a Magnum engine,V6 or V8.
Thanks,RT

UPDATE: While the van had spark,it ended up being a weak ignition coil.The primary/secondary resistance seemed to vary when checked,I swapped a good coil on and it fired up.This wa sfinally after checking inputs using an OBD1 scanner,all sensors looked good,no codes.Checked fuel pressure and volume,even disconnected the fuel line and ran fuel from an alternate source thinking the fuel may have been bad.Did a compression test as well,checked TDC vs distributor rotor alignment...All the parameters were there,just one was lazy! Thanks for all the input.
RT

Are the plugs and wires good? How about the cap & rotor? What is the gap on the plugs? This efi stuff works so well, we tend to forget they need plugs and wires (and a cap & rotor) sometimes.

The next thing that comes to mind is, water in the gas? If the gas don't burn, it won't run. If it has spark and doesn't run, (we are assuming it has spark while cranking) its not likely to be anything EFI related. Gene

Thanks Gene,The plugs/cap/rotor/wires all have about 5k on them,just over a year old.I do have spark at the plug end of the wire,but have yet to pull a plug out,I will do that tomorrow.The ignition rotor had some dust on it from the carbon center electrode but no tracking evidence.I won't rule out fuel yet but it looked ok when I checked pump volume to a glass jar.It would not fire on starting fluid,I will definitely pull the plugs tomorrow.Maybe bad fuel washed them out.I will report back!
Ron

If the “sock filter” below the submerged fuel pump is plugged with crud it will cause hard to diagnose stalling.

Check the EGR system to see if it is flowing at Max and keeping the spark from igniting a low oxygen mixture.

Having the paper 1994 or 1995 Field Service manual really helps with its flow charts trouble shooting section. Well worth the money.

https://www.ebay.com/itm/1995-Dodge-Ram-Van-Wagon-Shop-Manual-B1500-B2500-B3500-Repair-Service-Book-OEM/362515008614?hash=item5467940c66:g:P0IAAOSwL5BZ1Xyo

The Actron Scantool CP9110 with the Chrysler cartridge can read the OBD-I system.

https://www.ebay.com/itm/Actron-ScanTool-CP9113F-89-95-Chrysler-Cable-Software-Cartridge/113603400055?epid=1762509062&hash=item1a734a5177:g:TfYAAOSwQGFcT5oF

https://www.ebay.com/itm/Actron-ScanTool-Ford-1984-1995-Cars-And-Trucks-Diagnostic-Repair-Code-Scan/292589731943?hash=item441fb50067:g:6M0AAOSw-8pbdJu6

basically you need to do some investigating.

Run the computer codes, the Key on/off routine should work on the OBDI system. that will give you an area to look.

If there are no codes then you will have to verify fuel/spark/air and see which is failing.

No one is going to be able to remote view the answer without more info,

IIRc we had some at the shop that the drive gear wore out.Threw timing off.One guy played with one for 2 days before we found the dist drive gear was bad.They had a problem with them as we had more than one.Rocky

The van is running! I updated my first post with the info.
RT

Glad you got it running!

I had rough running issues with my '93 Dakota with the 3.9 that were coil related. I installed a new (stock) one, problem came back within a few days. Just for giggles, I threw on an MSD coil and no more problem. Its been on there for 3 yrs now. In addition to eliminating the original problem, I noticed the truck started quicker and got more consistent MPG.

Thanks,it was an odd one,I was betting on bad fuel from the way it stalled out.The coil resistance was a tad high,both primary and secondary.Easy fix once I figured it out!
RT